The Ghost In The Machine wrote:

On Sep 8, 2:30 pm, Jamie
t wrote:

The Ghost In The Machine wrote:






On Sep 8, 11:23 am, Jamie
et wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed

You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC coil

from chattering the armature. I am sure under DC operation, this may

effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

First you tell him not to be anal then you lube him up really good
then you ram your howdy doody linkage , what's up kiddo?
BOOWAHAHA...I JUST HAD TO, YOU HAD TO LOL
MOST UNIVERSAL MODELS ARE SOMEWHAT ERRATIC & DUBIOUS.
EUROS AND AMERICANS WILL ALWAYS BE THEMSELVES, BEST CAN BE DONE IS PUT
TO USE A CONVERTER DEVICE HARMONIC WITH BOTH WAVES PHI's. OR FREQUENCY
TO OR FROM THE INSTINCTIVE DEVICE BE IT AC OR DC PLAIN COIL OR
CONTACTOR WHICH IS HIS CONUNDRUM.

PLEASE SEND YOUR ARGUMENTS TO WHO GIVES A FLYING ****.COM :-)

TGITM

You must? You read and replied to it. It didn't concern you one bit how
ever, you were interested enough to push those fat fingers along while
burning all those calories sitting on your fat ass, just to post your
dumb ****..

You are taking up valuable space, move on and allow some one more
deserving to fill that gap.

Jamie


YOU THINK YOU KNOW SOMEONE MORE DESERVING?
**** YOU CUMSHOT..GO POP YOUR LOAD SOMEWHERE ELSE.
TELL YOUR FAT ASS FATHER I AM POSTING HIS NAME AS A REFERNCE ON A
HAUNTED HOUSE I HAVE MY EYES ON......BOOWAHAHAHAHA!
AND DONT ASK ME TO BILL THE GROUP FOR MY SERVICES EITHER.
THIS IS HOW WE DO IT.
PATECUM
TGITM
Useless pond scum..

jamie

On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
t wrote:

ehsjr wrote:
Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.


and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?




With the same current it wont, with higher curren ti will. IIRC you
proposed using 174v rms,




No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to get
smoothed DC closer to the relay's must-make current.




fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.




---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---


that would be ok on your specific relay, but
not a universal solution.




???




Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.




---
Show me.





If you want to go get some specs of other relays, you can. This is
starting to get silly.




Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed


You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC coil
from chattering the armature. I am sure under DC operation, this may
effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie


Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.

---
"Embedded."

Link?
---

The voltage ratings are the same. The coil is
actually of DC type..

---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.
---

They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation.
---

We also deal with solenoids to operate in the same manner..

---
Elaborate, please?
---

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie


--
JF

On 8/29/2011 1:21 AM, DaveC wrote:
I may be able to obtain a very small 2-pole 240 vac contactor I need rated
for 50 Hz only.

If I install it in N. America, what's the implication? Is the hold-in
magnetism less than if it were 60 Hz? Just noisy?

Hi, Dave -

Magnitisim is less.

Noisy depends on many things.


Please don't ask or suggest other sources. This is a very specific device and
I've not been able to locate other than this.

Thanks,
Dave


You should look at the manufacturer's specifications. The 50/60 Hz will
not matter much except for one thing: the coil current will be reduced
to ~50/60 of its nominal value (~83.3%) because of the coil inductance
(it has to do with total impedance, but this is a best guess without
knowing more about your contactor). Usually, the manufacturer will list
the minimum voltage the coil can handle.

At this point, my best guess is that the coil will suffer a 15% loss of
excitation voltage. If the mfr says that's too low, you may be in
trouble at low line.

Cheers,
John

John Fields wrote:

On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
t wrote:


ehsjr wrote:

Jamie wrote:


ehsjr wrote:


NT wrote:


On Sep 2, 8:41 pm, John Fields wrote:


Snipped a lot of repetitious, self serving nonsense.



and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?




With the same current it wont, with higher curren ti will. IIRC you
proposed using 174v rms,




No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to get
smoothed DC closer to the relay's must-make current.




fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.




---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---



that would be ok on your specific relay, but
not a universal solution.




???




Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.




---
Show me.





If you want to go get some specs of other relays, you can. This is
starting to get silly.




Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed


You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC coil
from chattering the armature. I am sure under DC operation, this may
effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie


Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed


Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.


---
"Embedded."

Link?
---


The voltage ratings are the same. The coil is
actually of DC type..


---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.

Well, then he lost unfairly.

Never heard of core hysteresis?



They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.


---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation.
---


We also deal with solenoids to operate in the same manner..


---
Elaborate, please?
---
Why?. You don't understand why, I guess?



Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie



I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.

Not saying that don't know what your doing but you tend to over look
a few things that have been done in the field over the years.


Jamie

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
t wrote:

I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.

Ummm.... I'm JL. What am I missing?



--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

On Sep 8, 5:11*pm, Jamie
t wrote:
The Ghost In The Machine wrote:





On Sep 8, 2:30 pm, Jamie
t wrote:

The Ghost In The Machine wrote:

On Sep 8, 11:23 am, Jamie
et wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. *I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. *Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. *The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. *So a specific link or links would be
most helpful.

Thanks,
Ed

You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC coil

from chattering the armature. I am sure under DC operation, this may

effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." *The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

*We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

First you tell him not to be anal then you lube him up really good
then you ram your howdy doody linkage , what's up kiddo?
BOOWAHAHA...I JUST HAD TO, YOU HAD TO LOL
MOST UNIVERSAL MODELS ARE SOMEWHAT ERRATIC & DUBIOUS.
EUROS AND AMERICANS WILL ALWAYS BE THEMSELVES, BEST CAN BE DONE IS PUT
TO USE A CONVERTER DEVICE HARMONIC WITH BOTH WAVES PHI's. OR FREQUENCY
TO OR FROM THE INSTINCTIVE DEVICE BE IT AC OR DC *PLAIN COIL OR
CONTACTOR WHICH IS HIS CONUNDRUM.

PLEASE SEND YOUR ARGUMENTS TO WHO GIVES A FLYING ****.COM :-)

TGITM

You must? You read and replied to it. It didn't concern you one bit how
ever, you were interested enough to push those fat fingers along while
burning all those calories sitting on your fat ass, just to post your
dumb ****..

* You are taking up valuable space, move on and allow some one more
deserving to fill that gap.

Jamie

YOU THINK YOU KNOW SOMEONE MORE DESERVING?
**** YOU CUMSHOT..GO POP YOUR LOAD SOMEWHERE ELSE.
TELL YOUR FAT ASS FATHER I AM POSTING HIS NAME AS A REFERNCE ON A
HAUNTED HOUSE I HAVE MY EYES ON......BOOWAHAHAHAHA!
AND DONT ASK ME TO BILL THE GROUP FOR MY SERVICES EITHER.
THIS IS HOW WE DO IT.
PATECUM
TGITM

Useless pond scum..

* jamie

PLEASE HOLD YOUR ANAL EMANATIONS FOR THE REST ROOM, JAMIKA.
YOU STINK !
TGITM

YOU CAN ALWAYS USE THE ONES DEVELOPED IN SPACE, WITH A NUCLEAR CORE.
THEY DETECT CHANGES AND OPEN OR CLOSE RESPECTIVELY, SOMETHING LIKE
SEMICONDUCTORS.
NO MAGNETIC DISTORTION INVOLVED.

BOOWAHAHAHAHAA.....WELCOME TO THE FUTURE.
PATECUM
TGITM

On Sep 8, 9:56*pm, Jamie
t wrote:
John Fields wrote:
On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
t wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. *I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. *Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. *The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. *So a specific link or links would be
most helpful.

Thanks,
Ed

*You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC coil
from chattering the armature. I am sure under DC operation, this may
effect the calculations.

*There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." *The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.

---
"Embedded."

Link?
---

The voltage ratings are the same. The coil is
actually of DC type..

---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.

Well, then he lost unfairly.

* Never heard of core hysteresis?







They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation. *
---

*We also deal with solenoids to operate in the same manner..

---
Elaborate, please?
---

Why?. You don't understand why, I guess?



Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.

* *Not saying that don't know what your doing but you tend to over look
a few things that have been done in the field over the years.

* Jamie

Crunch !!!

Jamie wrote:
ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.


and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?





With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,





No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.





fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.





---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---


that would be ok on your specific relay, but
not a universal solution.





???





Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.





---
Show me.






If you want to go get some specs of other relays, you can. This is
starting to get silly.





Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed



You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie


Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie


I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Jeff Liebermann wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
? wrote:

?I was going to make a whole page for you to read, but I know how you
?carry on with JL, I won't be another one of your imaginary conquest.

Ummm.... I'm JL. What am I missing?


That there is another JL on the group.


--
You can't have a sense of humor, if you have no sense.

On Sep 9, 3:44*am, "Michael A. Terrell"
wrote:
Jeff Liebermann wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
? wrote:

?I was going to make a whole page for you to read, but I know how you
?carry on with JL, I won't be another one of your imaginary conquest.

Ummm.... I'm JL. *What am I missing?

* *That there is another JL on the group.

--
You can't have a sense of humor, if you have no sense.

YOU SUCK.....STAY OFF USENET DUDE.
YOU'RE ON BORROWED WAVELENGTH AS IT IS.
GO HUNT DOWN SOME TERRORISTS OR DO SOMETHING HELPFUL INSTEAD.
CHANGE YOUR NAME, TRY COOKIE MONSTER.
BOOWAHAHAHAHA,.....YOU FINK !
PATECUM
TGITM

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
t wrote:

John Fields wrote:

On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
t wrote:

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.


---
"Embedded."

Link?
---


The voltage ratings are the same. The coil is
actually of DC type..


---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.

Well, then he lost unfairly.

---
Instead of blathering on about something of which you obviously have
little knowledge, why not try it?

That is, get a few relays with DC coils, drive their coils with
half-wave rectified AC, and post back with the results.
---

Never heard of core hysteresis?

---
Sure, but for relays it's usually defined as the difference between
the must-make and must-break voltage instead of this:

http://www.google.com/imgres?imgurl=...9QEwAQ&dur=468
Now we both know!
---

They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.


---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation.
---


We also deal with solenoids to operate in the same manner..


---
Elaborate, please?
---

Why?. You don't understand why, I guess?

---
Well, although a case might be made for:

..AC---[DIODE]--+-------+
.. | |K
.. [COIL] DIODE
.. | |
..AC-------------+-------+


I've never heard of a DC solenoid being converted to AC by using a
shunt diode, have you?

If so, why not give us the benefit of your knowledge by elaborating on
the subject?
---

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie



I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.

---
Aw... Poor baby.

Afraid of making and having to own up to an error, are you?
---

Not saying that don't know what your doing but you tend to over look
a few things that have been done in the field over the years.

---
Like what, the development of latching relays with infinite gain?

--
JF

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.


and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?






With the same current it wont, with higher curren ti will.
IIRC you
proposed using 174v rms,






No, I merely added a capacitor across the output of _your_
proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order
to get
smoothed DC closer to the relay's must-make current.






fwliw I said use diodes, you came back with a FW BR. I dont
think it
matters.






---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---


that would be ok on your specific relay, but
not a universal solution.






???






Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.






---
Show me.







If you want to go get some specs of other relays, you can. This is
starting to get silly.






Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed




You must remember that AC coil relays are wound a little
different, its not just induction here. Inter pole windings help
keep the AC coil from chattering the armature. I am sure under DC
operation, this may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie


Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed


Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie


I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed
Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

These are just some examples out there.

I don't know what "NT" had in mind, if this isn't what
you're after, than I'll stand down.

Btw.
P&B got bought out, in case any one didn't know.


Jamie

John Fields wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
t wrote:


John Fields wrote:


On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
et wrote:


Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.


---
"Embedded."

Link?
---



The voltage ratings are the same. The coil is
actually of DC type..


---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.

Well, then he lost unfairly.


---
Instead of blathering on about something of which you obviously have
little knowledge, why not try it?

That is, get a few relays with DC coils, drive their coils with
half-wave rectified AC, and post back with the results.
---


Never heard of core hysteresis?


---
Sure, but for relays it's usually defined as the difference between
the must-make and must-break voltage instead of this:

http://www.google.com/imgres?imgurl=...9QEwAQ&dur=468
Now we both know!
---


They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.


---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation.
---



We also deal with solenoids to operate in the same manner..


---
Elaborate, please?
---

Why?. You don't understand why, I guess?


---
Well, although a case might be made for:

.AC---[DIODE]--+-------+
. | |K
. [COIL] DIODE
. | |
.AC-------------+-------+


I've never heard of a DC solenoid being converted to AC by using a
shunt diode, have you?

If so, why not give us the benefit of your knowledge by elaborating on
the subject?
---


Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie



I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.


---
Aw... Poor baby.

Afraid of making and having to own up to an error, are you?
---


Not saying that don't know what your doing but you tend to over look
a few things that have been done in the field over the years.


---
Like what, the development of latching relays with infinite gain?

No error, you're the one with egg on the face loser, and this will be
my last to you. I will not be another JL stick for you to crack your
false sense of victory with.

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Just because you haven't seen it or think it shouldn't be done means
every one else should bend over to your rule? Sorry sucker, this is why
people move on and those like yourself are left holding the bag.


And while your reading that doc, if you even do, the comment about
unfiltered DC where the armature might experience movement, they don't
say it will. That is because it depends on the mechanical design of the
relay and type of system in place.

Further more, I guess you've never seen the old trick of operating a
small DC relay with half wave to force the unit to slightly vibrate, not
enough to actually see it how ever, when doing this, you could force the
contact surface to keep themselves cleaner and thus cheap relays would
be used to pass reference signals through. This would be evident over
time from apparent ware on the contacts from mechanical movement and no
arc which would otherwise do the wetting process via the plasma process.

By and have a good life..


Jamie

The Ghost In The Machine wrote:

On Sep 9, 3:44 am, "Michael A. Terrell"
wrote:

Jeff Liebermann wrote:


On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
et? wrote:

?I was going to make a whole page for you to read, but I know how you
?carry on with JL, I won't be another one of your imaginary conquest.

Ummm.... I'm JL. What am I missing?

That there is another JL on the group.

--
You can't have a sense of humor, if you have no sense.


YOU SUCK.....STAY OFF USENET DUDE.
YOU'RE ON BORROWED WAVELENGTH AS IT IS.
GO HUNT DOWN SOME TERRORISTS OR DO SOMETHING HELPFUL INSTEAD.
CHANGE YOUR NAME, TRY COOKIE MONSTER.
BOOWAHAHAHAHA,.....YOU FINK !
PATECUM
TGITM
You know what's even funnier than your stupidity? Your lack of
ability to convey over what you really want to say in english,
it's hilarious..

Jamie


"Just for you:

SOME PEOPLE ARE LIKE SLINKIES. NOT REALLY GOOD FOR ANYTHING BUT
THEY BRING A SMILE TO YOUR FACE WHEN PUSHED DOWN THE STAIRS.
"

Jeff Liebermann wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
t wrote:


I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.


Ummm.... I'm JL. What am I missing?



Absolutely nothing sir

Jamie

On Fri, 09 Sep 2011 12:14:26 -0400, Jamie
t wrote:


No error, you're the one with egg on the face loser, and this will be
my last to you.

---
Thanks, I'm looking forward to it!

--
JF

Jamie wrote:
ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields
wrote:

Snipped a lot of repetitious, self serving nonsense.


and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?







With the same current it wont, with higher curren ti will.
IIRC you
proposed using 174v rms,







No, I merely added a capacitor across the output of _your_
proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order
to get
smoothed DC closer to the relay's must-make current.







fwliw I said use diodes, you came back with a FW BR. I dont
think it
matters.







---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---


that would be ok on your specific relay, but
not a universal solution.







???







Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.







---
Show me.








If you want to go get some specs of other relays, you can. This is
starting to get silly.







Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed





You must remember that AC coil relays are wound a little
different, its not just induction here. Inter pole windings help
keep the AC coil from chattering the armature. I am sure under DC
operation, this may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil
also
plays a role in this.

Jamie


Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed



Don't be anal, they make relays that will do AD/DC because they have
a diode imbedded in them. The voltage ratings are the same. The coil
is actually of DC type.. They also have relays with shunt diodes
built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie


I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.


It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.


These are just some examples out there.

I don't know what "NT" had in mind, if this isn't what
you're after, than I'll stand down.


Ok.

Ed

Btw.
P&B got bought out, in case any one didn't know.


Jamie

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed


Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf


Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.



The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie

On 9/9/2011 6:30 PM, Jamie wrote:
ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed


Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf


Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.



The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie


I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S

On 9/9/2011 6:53 PM, Jamie wrote:
John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed



Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf



Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.


It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.


No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.




The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie


I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S
If you have IR gun/camera, you should also do some comparisons.

Jamie

Sorry, I do not.

John S

John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed



Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf



Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.


It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.


No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.




The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie


I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S
If you have IR gun/camera, you should also do some comparisons.

Jamie

On Sep 9, 12:49*pm, Jamie
t wrote:
The Ghost In The Machine wrote:





On Sep 9, 3:44 am, "Michael A. Terrell"
wrote:

Jeff Liebermann wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
et? wrote:

?I was going to make a whole page for you to read, but I know how you
?carry on with JL, I won't be another one of your imaginary conquest.

Ummm.... I'm JL. *What am I missing?

* That there is another JL on the group.

--
You can't have a sense of humor, if you have no sense.

YOU SUCK.....STAY OFF USENET DUDE.
YOU'RE ON BORROWED WAVELENGTH AS IT IS.
GO HUNT DOWN SOME TERRORISTS OR DO SOMETHING HELPFUL INSTEAD.
CHANGE YOUR NAME, TRY COOKIE MONSTER.
BOOWAHAHAHAHA,.....YOU FINK !
PATECUM
TGITM

You know what's even funnier than your stupidity? Your lack of
ability to convey over what you really want to say in english,
it's hilarious..

* Jamie

"Just for you:

* SOME PEOPLE ARE LIKE SLINKIES. NOT REALLY GOOD FOR ANYTHING BUT
* THEY BRING A SMILE TO YOUR FACE WHEN PUSHED DOWN THE STAIRS.
"
WHY YOU EVIL LITTLE *******.
AS FAR AS I AM CONCERNED, YOU CAN NOW CHOKE ON YOUR FAGGOTY STUPID AC/
DC MADE UP THEORIES.
TGITM

On Sep 9, 7:44*pm, John S wrote:
On 9/9/2011 6:53 PM, Jamie wrote:





John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.

Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.

The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.

Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie

I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S
If you have IR gun/camera, you should also do some comparisons.

Jamie

Sorry, I do not.

John S

CAN IT BUDDY!!!

On Fri, 09 Sep 2011 12:14:26 -0400, Jamie
t wrote:

John Fields wrote:

On Thu, 08 Sep 2011 21:56:25 -0400, Jamie
t wrote:


John Fields wrote:


On Thu, 08 Sep 2011 11:23:56 -0400, Jamie
jamie_ka1lpa_not_valid_after_ka1lpa_@charter. net wrote:


Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them.


---
"Embedded."

Link?
---



The voltage ratings are the same. The coil is
actually of DC type..


---
If you're saying that half-wave rectified 12VAC will cause the
armature of a relay with a 12VDC coil to close, instead of chatter,
then I'd have to ask for proof since I have empirical evidence which
refutes your assertion.

Years ago, Larkin and I had the same argument here.

He took your position and lost the argument.

Well, then he lost unfairly.


---
Instead of blathering on about something of which you obviously have
little knowledge, why not try it?

That is, get a few relays with DC coils, drive their coils with
half-wave rectified AC, and post back with the results.
---


Never heard of core hysteresis?


---
Sure, but for relays it's usually defined as the difference between
the must-make and must-break voltage instead of this:

http://www.google.com/imgres?imgurl=...9QEwAQ&dur=468
Now we both know!
---


They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.


---
What does that have to do with driving DC coil relays with rectified
AC, or driving AC coil relays with DC?

From my experience, those diodes are used in order to return the
coil's inductive turn-off transient to the positive supply in order to
keep E = LdI/dT from ruining a relay driver's day, and to save the
user the expense of an extra part and the PCB real estate needed for
its implementation.
---



We also deal with solenoids to operate in the same manner..


---
Elaborate, please?
---

Why?. You don't understand why, I guess?


---
Well, although a case might be made for:

.AC---[DIODE]--+-------+
. | |K
. [COIL] DIODE
. | |
.AC-------------+-------+


I've never heard of a DC solenoid being converted to AC by using a
shunt diode, have you?

If so, why not give us the benefit of your knowledge by elaborating on
the subject?
---


Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html


Jamie



I was going to make a whole page for you to read, but I know how you
carry on with JL, I won't be another one of your imaginary conquest.


---
Aw... Poor baby.

Afraid of making and having to own up to an error, are you?
---


Not saying that don't know what your doing but you tend to over look
a few things that have been done in the field over the years.


---
Like what, the development of latching relays with infinite gain?

No error, you're the one with egg on the face loser, and this will be
my last to you. I will not be another JL stick for you to crack your
false sense of victory with.

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Just because you haven't seen it or think it shouldn't be done means
every one else should bend over to your rule? Sorry sucker, this is why
people move on and those like yourself are left holding the bag.

---
I read that appnote when Ed posted it, a while ago.

I've never said anyone should bend over to my "rule", whatever fears
that thought brings into your apparently tawdry life.

Instead, I generally choose to present empirical data backed up with a
little math in order to prove a point.

I've pretty much always done it that way and have used the results of
the experiments to prove whether my conjectures were wrong or right,
posted the results, and publicly admitted when I was wrong.

That modus vivendi seems to be beyond your capabilities since you only
post anecdotal data which can't be verified.
---

And while your reading that doc, if you even do, the comment about
unfiltered DC where the armature might experience movement, they don't
say it will. That is because it depends on the mechanical design of the
relay and type of system in place.

---
Like you know something about that?
---

Further more, I guess you've never seen the old trick of operating a
small DC relay with half wave to force the unit to slightly vibrate, not
enough to actually see it how ever, when doing this, you could force the
contact surface to keep themselves cleaner and thus cheap relays would
be used to pass reference signals through. This would be evident over
time from apparent ware on the contacts from mechanical movement and no
arc which would otherwise do the wetting process via the plasma process.

---
Got some data?

--
JF

On 9/9/2011 6:53 PM, Jamie wrote:
John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed



Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf



Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.


It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.


No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.




The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie


I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S
If you have IR gun/camera, you should also do some comparisons.

Jamie


BTW, Jamie, if by IR gun/camera you are interested in coil temperature
rise, that can be done using the copper resistance vs temperature rise
method.

And, which comparisons are you referring to?

John S

John S wrote:

On 9/9/2011 6:53 PM, Jamie wrote:

John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed




Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf




Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.


It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.



No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.


Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.





The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.


Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie


I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S

If you have IR gun/camera, you should also do some comparisons.

Jamie



BTW, Jamie, if by IR gun/camera you are interested in coil temperature
rise, that can be done using the copper resistance vs temperature rise
method.

And, which comparisons are you referring to?

John S


I have IR equipment, I just thought that most people that work in this
field would at least have a small hand held unit. When doing quick
checks between induction and DC R it's a quick and dirty way to
determine the operating range of AC coil in a DC environment.

Most AC coil design i've seen try to balance between DC R and
induction, for obvious reasons.

We use one of the Humphrey solenoid valve series at work that employs
a single DIODE in series to operate the coil from the 120AC control
voltage in many different applications.

I suppose it's possible those units actually have a 240 AC coil in
them and that is done for 120 volt operation. Or say that it could be
done to help keep the valve from sticking, thus allowing it to buzz
just a little how ever, these unit runs perfectly quiet and if they're
buzzing I can't hear or feel it? Depends on the hysteresis in the core I
guess.

Have a good day.

Jamie

On Sep 11, 9:05*pm, Jamie
t wrote:
John S wrote:
On 9/9/2011 6:53 PM, Jamie wrote:

John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.

Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.

The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.

Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie

I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S

If you have IR gun/camera, you should also do some comparisons.

Jamie

BTW, Jamie, if by IR gun/camera you are interested in coil temperature
rise, that can be done using the copper resistance vs temperature rise
method.

And, which comparisons are you referring to?

John S

* I have IR equipment, I just thought that most people that work in this
field would at least have a small hand held unit. *When doing quick
checks between induction and DC R it's a quick and dirty way to
determine the operating range of AC coil in a DC environment.

* * *Most AC coil design i've seen try to balance between DC R and
induction, for obvious reasons.

* * *We use one of the Humphrey solenoid valve series at work that employs
a single DIODE in series to operate the coil from the 120AC control
voltage in many different applications.

* * * I suppose it's possible those units actually have a 240 AC coil in
them and that is done for 120 volt operation. Or say that it could be
done to help keep the valve from sticking, thus allowing it to buzz
just a little how ever, these unit runs perfectly quiet and if they're
buzzing I can't hear or feel it? Depends on the hysteresis in the core I
guess.

Have a good day.

* Jamie

YES JAMIE TAKE YOUR HUMPHREYS BABY PILLS...
YOU ARE HYSTERICAL...BOOWAHAHAHAHA!

THE HYSTERISIS CURVE IS A CHARACTERISTIC OF A WAVE FORM., NOT INSIDE
THE CORE BUT THE INPUT/OUTPUT SIGNAL.......

TRY AND HAVE A NICE WEEK
PATTYCAKE
TGITM

BOOWAHAHAHAHAHAHA !

The Ghost In The Machine wrote:
On Sep 11, 9:05 pm, Jamie
t wrote:

John S wrote:

On 9/9/2011 6:53 PM, Jamie wrote:

John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.

Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.

The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.

Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie

I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S

If you have IR gun/camera, you should also do some comparisons.

Jamie

BTW, Jamie, if by IR gun/camera you are interested in coil temperature
rise, that can be done using the copper resistance vs temperature rise
method.

And, which comparisons are you referring to?

John S

I have IR equipment, I just thought that most people that work in this
field would at least have a small hand held unit. When doing quick
checks between induction and DC R it's a quick and dirty way to
determine the operating range of AC coil in a DC environment.

Most AC coil design i've seen try to balance between DC R and
induction, for obvious reasons.

We use one of the Humphrey solenoid valve series at work that employs
a single DIODE in series to operate the coil from the 120AC control
voltage in many different applications.

I suppose it's possible those units actually have a 240 AC coil in
them and that is done for 120 volt operation. Or say that it could be
done to help keep the valve from sticking, thus allowing it to buzz
just a little how ever, these unit runs perfectly quiet and if they're
buzzing I can't hear or feel it? Depends on the hysteresis in the core I
guess.

Have a good day.

Jamie


YES JAMIE TAKE YOUR HUMPHREYS BABY PILLS...
YOU ARE HYSTERICAL...BOOWAHAHAHAHA!

THE HYSTERISIS CURVE IS A CHARACTERISTIC OF A WAVE FORM., NOT INSIDE
THE CORE BUT THE INPUT/OUTPUT SIGNAL.......

TRY AND HAVE A NICE WEEK
PATTYCAKE
TGITM

BOOWAHAHAHAHAHAHA !
Goes to show what you know about induction and construction of such things.

Buzz off..

Jamie

On Sep 12, 11:27*am, Jamie
t wrote:
The Ghost In The Machine wrote:



On Sep 11, 9:05 pm, Jamie
t wrote:

John S wrote:

On 9/9/2011 6:53 PM, Jamie wrote:

John S wrote:

On 9/9/2011 6:30 PM, Jamie wrote:

ehsjr wrote:

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

Is this what you're looking for ?

http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

Geeeez. I posted that link in my _first_ post in the thread, and
you replied to that post. I guess you either didn't read the post
properly, or didn't understand it. The ap note does not agree with
the DC at ~50% of AC rating idea - details are given in that post.

Sorry, I didn't see that.

It explains operating AC coils on DC and AC coils using
the internal DIODES for shading rings design.

No, that wasn't a hack as far as the diodes goes, that is a practical
design in a family of relays, We use large contactors with the dual
coil and diodes in them. You don't see this from the out side world but
they are incased in the encapsulation. Those particular types can have
DC going directly to them. It's just the way they are with obvious
reasons.

Yup. To operate an AC relay on DC, (the Tyco ap note says
doing so is impractical, but that you can do it in an
emergency) you should install a residual and you must lower
the voltage below the AC rating. An AC rated coil needs DC
in excess of 61% of the ac rating on the minimum side, and
less than 82% of the ac rating on the maximum side, per the
example given in the ap note.

The app note is pointing equivalent power dissipation, as you
know relays will pull in at a lower current So I don't see a problem
here.

Why don't you put a few AC types on the bench and test them yourself?

I think you'd be surprised in what you find. Lab testing tells a lot
about what you can do.

The only problem I have found with this practice of using AC on DC is
that some AC units use material that has a high hysteresis and the
AC will help keep this down. They do this in cases where they don't use
the dual coil system. In DC operation, I've seen it over magnetize the
core and cause a little slow release on the contacts. But that may not
be such a big deal in most cases.

Have a good day.

Jamie

I have an Essex contactor which was removed from my old A/C outside
unit. It has a 24VAC 50/60 Hz coil. I can make some measurements on it
if anyone is interested.

John S

If you have IR gun/camera, you should also do some comparisons.

Jamie

BTW, Jamie, if by IR gun/camera you are interested in coil temperature
rise, that can be done using the copper resistance vs temperature rise
method.

And, which comparisons are you referring to?

John S

*I have IR equipment, I just thought that most people that work in this
field would at least have a small hand held unit. *When doing quick
checks between induction and DC R it's a quick and dirty way to
determine the operating range of AC coil in a DC environment.

* * Most AC coil design i've seen try to balance between DC R and
induction, for obvious reasons.

* * We use one of the Humphrey solenoid valve series at work that employs
a single DIODE in series to operate the coil from the 120AC control
voltage in many different applications.

* * *I suppose it's possible those units actually have a 240 AC coil in
them and that is done for 120 volt operation. Or say that it could be
done to help keep the valve from sticking, thus allowing it to buzz
just a little how ever, these unit runs perfectly quiet and if they're
buzzing I can't hear or feel it? Depends on the hysteresis in the core I
guess.

Have a good day.

*Jamie

YES JAMIE TAKE YOUR HUMPHREYS BABY PILLS...
YOU ARE HYSTERICAL...BOOWAHAHAHAHA!

THE HYSTERISIS CURVE IS A CHARACTERISTIC OF A WAVE FORM., NOT INSIDE
THE CORE BUT *THE INPUT/OUTPUT SIGNAL.......

TRY AND HAVE A NICE WEEK
PATTYCAKE
TGITM

BOOWAHAHAHAHAHAHA !

Goes to show what you know about induction and construction of such things.

* Buzz off..

Jamie

PHASE OFF CREEP ..
I AINT NOBODY FOR YOU OR ANY OF YOU SUBLIMIE SLIME TROLLS TO BE
****ING WITH.

YOU DONT KNOW **** ABOUT BEING PEOFESSIONAL AND POLITE, ALL YOU DO IS
SPOUT OFF THEORETICAL CRAP AND INSULT OTHERS.

THE GRAVE AND THE PITS OF HELL WILL BE YOUR REWARD.

PATECUM

On Aug 29, 2:21*am, DaveC wrote:
I may be able to obtain a very small 2-pole 240 vac contactor I need rated
for 50 Hz only.

If I install it in N. America, what's the implication? Is the hold-in
magnetism less than if it were 60 Hz? Just noisy?

Please don't ask or suggest other sources. This is a very specific device and
I've not been able to locate other than this.

Thanks,
Dave

There are NO Implications...
Even the old models are not noisy at all, just make sure you bolt down
everything tight to the framework.
TGITM

On Sep 9, 5:33*am, ehsjr wrote:
Jamie wrote:
ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. *I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. *Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. *The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. *So a specific link or links would be
most helpful.

Thanks,
Ed

* You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

* There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
*plays a role in this.

*Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." *The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

* We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? *Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. *You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." *That is * *NOT* * what NT said. *He talks about the dc
coil rating being half the ac rating.

Ed


I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.


NT

NT wrote:

On Sep 9, 5:33 am, ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed

You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed



I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.


NT
You must remember that a lot of viewers here are not or have not been
exposed to some of the large body and odd styles of relays made over the
years.

What I love is when one of the dual coils that have the Diodes in them
end up shorting a diode. THe unit will still work, it just makes the
contactor noisy, in some cases, very noisy, but they still work.

Jamie

NT wrote:
On Sep 9, 5:33 am, ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed

You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed



I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.


NT

Thanks. I found the same thing as you when I googled - the dual
rated relays were all rated at the same voltage - and that prompted
my original question. Maybe Jamie has a specific reference to
an old relay that has the dual rating with the DC rating at ~1/2
the AC rating. Do you remember if the ones you wrote about
had dual coils - or was it just single coil relays rated that way?

I suppose it doesn't matter if those relays are no longer available,
but there is a fascination in trying to figure it out. I can't see
how/why they would make a relay that operates on DC at half the AC
rating. The physics says it can't be a single coil relay, unless
the manufacturer is playing fast and loose with the ratings.
I can see it if the thing has a cap across the coil and a dropping
resistor in series, but then I don't see why a manufacturer would
do that.

Ed

On Sep 19, 5:25*pm, ehsjr wrote:
NT wrote:
On Sep 9, 5:33 am, ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. *I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. *Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. *The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts"..
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. *So a specific link or links would be
most helpful.

Thanks,
Ed

*You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

*There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." *The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

*We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? *Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. *You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." *That is * *NOT* * what NT said. *He talks about the dc
coil rating being half the ac rating.

Ed

I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.

NT

Thanks. *I found the same thing as you when I googled *- the dual
rated relays were all rated at the same voltage - and that prompted
my original question. *Maybe Jamie has a specific reference to
an old relay that has the dual rating with the DC rating at ~1/2
the AC rating. * Do you remember if the ones you wrote about
had dual coils - or was it just single coil relays rated that way?

I suppose it doesn't matter if those relays are no longer available,
but there is a fascination in trying to figure it out. *I can't see
how/why they would make a relay that operates on DC at half the AC
rating. *The physics says it can't be a single coil relay, unless
the manufacturer is playing fast and loose with the ratings.
I can see it if the thing has a cap across the coil and a dropping
resistor in series, but then I don't see why a manufacturer would
do that.

Ed

They were all single coil. With the right ratio of L and R, 24v ac and
12v dc will give the same coil current.


NT

On Sep 19, 5:25*pm, ehsjr wrote:
NT wrote:
On Sep 9, 5:33 am, ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. *I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. *Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. *The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts"..
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. *So a specific link or links would be
most helpful.

Thanks,
Ed

*You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

*There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." *The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

*We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? *Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. *You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." *That is * *NOT* * what NT said. *He talks about the dc
coil rating being half the ac rating.

Ed

I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.

NT

Thanks. *I found the same thing as you when I googled *- the dual
rated relays were all rated at the same voltage - and that prompted
my original question. *Maybe Jamie has a specific reference to
an old relay that has the dual rating with the DC rating at ~1/2
the AC rating. * Do you remember if the ones you wrote about
had dual coils - or was it just single coil relays rated that way?

I suppose it doesn't matter if those relays are no longer available,
but there is a fascination in trying to figure it out. *I can't see
how/why they would make a relay that operates on DC at half the AC
rating. *The physics says it can't be a single coil relay, unless
the manufacturer is playing fast and loose with the ratings.
I can see it if the thing has a cap across the coil and a dropping
resistor in series, but then I don't see why a manufacturer would
do that.

Ed

They were all single coil. With the right ratio of L and R, 24v ac and
12v dc will give the same coil current. It seems today's miniature pcb
relays are more R dominated, hence the currents are similar at 12v ac
and 12v dc.


NT

NT wrote:

On Sep 19, 5:25 pm, ehsjr wrote:

NT wrote:

On Sep 9, 5:33 am, ehsjr wrote:

Jamie wrote:

ehsjr wrote:

Jamie wrote:

ehsjr wrote:

NT wrote:

On Sep 2, 8:41 pm, John Fields wrote:

Snipped a lot of repetitious, self serving nonsense.

and if the relay is
designed to operate on AC with a certain RMS current in its
coil, how
can it possibly overheat if that current is DC?

With the same current it wont, with higher curren ti will. IIRC
you
proposed using 174v rms,

No, I merely added a capacitor across the output of _your_ proposed
full wave rectified 120 VRMS 60Hz source (170V peak) in order to
get
smoothed DC closer to the relay's must-make current.

fwliw I said use diodes, you came back with a FW BR. I dont think it
matters.

---
Then show me your circuit.

Just in case you've forgotten, your suggestion was to use a 240V AC
relay using diodes and 120V mains.
---

that would be ok on your specific relay, but
not a universal solution.

???

Your proposd BR+C delivers the right i for one specific relay. For
some relays it will fry them.

---
Show me.

If you want to go get some specs of other relays, you can. This is
starting to get silly.

Worth investigating, to me. JF gave a specific relay & numbers. I
tried to find a relay to support the idea that an AC/DC relay would
be happy with DC voltage about 50% of AC rating. Can you please
provide a reference?

Meanwhile, what I did find was an ap note from Tyco entitled
"Operating DC Relays from AC and Vice-Versa" .
http://relays.te.com/appnotes/app_pdfs/13c3250.pdf

It does not agree with the DC at ~50% of AC rating idea. It uses
the example of a KR series relay coil. Their example uses a 12
volt AC relay fed by DC. The example states that the "DC voltage
cannot exceed 9.8 volts", and "should not be lower than 7.35 volts".
Thus the DC range would be ~61%(minimum) to ~81% (maximum) of the
12VAC rating.

Extrapolating, it does agree with the idea of BR+C fed by 120 for
the 240 volt relay, insofar as the DC voltage:
~146VDC min to ~194VDC max, which makes the midpoint ~170VDC.
That's very close to ~168 from the BR+C

Regarding coil ratings, I've worked with DC relays, and I've worked
with AC relays, but I haven't worked with AC/DC coil relays, so
I can't speak from experience with them, and I haven't found
anything yet specifically dealing with that, other than the
link I found to Tyco. So a specific link or links would be
most helpful.

Thanks,
Ed

You must remember that AC coil relays are wound a little different,
its not just induction here. Inter pole windings help keep the AC
coil from chattering the armature. I am sure under DC operation, this
may effect the calculations.

There are some AC coil relays that do not do this and thus the 50%
voltage for DC should come close, but then again, DC R in the coil also
plays a role in this.

Jamie

Your post contains nothing specific and does not address
my question.

I am looking for a specific link or links that shows a datasheet,
ap note, or example of a relay that NT has in mind. Do you have one?

I want specifics, like John Fields posted; the specs that NT
said you could get: "If you want to go get some specs of other
relays, you can." The specs I have been able to find so far
do not demonstrate what NT was talking about, thus my post
asking for a reference.

Ed

Don't be anal, they make relays that will do AD/DC because they have a
diode imbedded in them. The voltage ratings are the same. The coil is
actually of DC type.. They also have relays with shunt diodes built into
them, for those you need to insure the polarity is correct and are
strictly DC only.

We also deal with solenoids to operate in the same manner..

Scroll down and read about AC coils, I am sure if you're looking for
some more detailed information you can find it, but this will explain
some of the differences.

http://www.ehow.com/about_6498402_di...elay-coil.html

Jamie

I don't know how to make it clear enough for you to understand.
While I do appreciate your attempt to help, I must say it misses
the point.

I want a *specific* link to an *AC/DC* relay of the type *NT*
had in mind, or to an ap note or reference that discusses a relay
coil that is rated for *both* AC and DC as he indicated.

Do you have a link to what NT was talking about? Here's what
he said:
"The various ones I've seen that have coil 2 ratings, one for ac one
for dc, have consistently had the dc coil rating be half the ac
voltage rating."

I _do not_ need generalizations, hand waving and condescending
responses. You mentioned a relay that will "do" DC because it
has an imbedded (sic) diode and say "The voltage ratings are the
same." That is *NOT* what NT said. He talks about the dc
coil rating being half the ac rating.

Ed

I got the time to do some googling, and the dual rated relays I found
were all rated at teh same voltage ac and dc, albeit with 2 different
currents. The dual rated ones I used were all a fair few years ago, I
remember it pretty well though, being struck at first by the dual
rating thing. I wonder if design has shifted over time. These old
relays were quite a lot bigger than the typical pcb ones of today,
which would fit with more L & less R in their coils.

NT

Thanks. I found the same thing as you when I googled - the dual
rated relays were all rated at the same voltage - and that prompted
my original question. Maybe Jamie has a specific reference to
an old relay that has the dual rating with the DC rating at ~1/2
the AC rating. Do you remember if the ones you wrote about
had dual coils - or was it just single coil relays rated that way?

I suppose it doesn't matter if those relays are no longer available,
but there is a fascination in trying to figure it out. I can't see
how/why they would make a relay that operates on DC at half the AC
rating. The physics says it can't be a single coil relay, unless
the manufacturer is playing fast and loose with the ratings.
I can see it if the thing has a cap across the coil and a dropping
resistor in series, but then I don't see why a manufacturer would
do that.

Ed


They were all single coil. With the right ratio of L and R, 24v ac and
12v dc will give the same coil current. It seems today's miniature pcb
relays are more R dominated, hence the currents are similar at 12v ac
and 12v dc.


NT
I think you're studdering today, seems like we're getting double post!

To add to that comment, we still have standard 24V AC coil relays that
we can use with 12VDC. With the R of the coil, its a good way to lower
the Q of the coil and remove side effects on the control line. It Just
happens to work out for many cases that you can do this.

Jamie