This 28 year old Stanley Vemco automatic gate uses mechanical relays. The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can hear a
relay click with no problem, then the gate opens. Just before the gate is
fully open, it enables a sensor switch which interrupts power to the motor
relay. Then, you can hear one of the relays make a chattering noise which
decays in about two seconds. The same thing happens when the gate closes. It
seems to have gotten louder over the years. Since the entire circuit is AC,

"David Farber" wrote in message
...
This 28 year old Stanley Vemco automatic gate uses mechanical relays. The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can hear
a
relay click with no problem, then the gate opens. Just before the gate is
fully open, it enables a sensor switch which interrupts power to the motor
relay. Then, you can hear one of the relays make a chattering noise which
decays in about two seconds. The same thing happens when the gate closes.
It
seems to have gotten louder over the years. Since the entire circuit is
AC,



Sorry about this incomplete message. It was erroneously sent. I think the
solution will be to replace the noisy relays with new ones.

--
David Farber
David Farber's Service Center
L.A., CA

On Jun 21, 2:53 pm, "David Farber" wrote:

Sorry about this incomplete message. It was erroneously sent. I think the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA

wrote in message
oups.com...
On Jun 21, 2:53 pm, "David Farber" wrote:

Sorry about this incomplete message. It was erroneously sent. I think the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA


Might be worth checking to see if there's a diode or rectifier bridge in
there. A shorted diode could cause AC to be fed to relay coils expecting DC
which will make them chatter or buzz.

"James Sweet" wrote in message
news:zWTei.71$ss5.68@trndny03...

wrote in message
oups.com...
On Jun 21, 2:53 pm, "David Farber" wrote:

Sorry about this incomplete message. It was erroneously sent. I think
the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA


Might be worth checking to see if there's a diode or rectifier bridge in
there. A shorted diode could cause AC to be fed to relay coils expecting
DC
which will make them chatter or buzz.



I dismantled this thing last year. There are only switches and relays. But
now that you mention it, maybe some of the relays were improperly replaced
with dc relays or the diodes are missing? I'm not the original person
working on this controller.

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

On Fri, 22 Jun 2007 17:47:11 GMT, "James Sweet"
wrote:


wrote in message
roups.com...
On Jun 21, 2:53 pm, "David Farber"
wrote:

Sorry about this incomplete message. It was erroneously sent. I
think the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA


Might be worth checking to see if there's a diode or rectifier bridge
in
there. A shorted diode could cause AC to be fed to relay coils
expecting DC
which will make them chatter or buzz.


It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

"Ross Herbert" wrote in message
...
On Fri, 22 Jun 2007 17:47:11 GMT, "James Sweet"
wrote:


wrote in message
roups.com...
On Jun 21, 2:53 pm, "David Farber"
wrote:

Sorry about this incomplete message. It was erroneously sent. I
think the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA


Might be worth checking to see if there's a diode or rectifier bridge
in
there. A shorted diode could cause AC to be fed to relay coils
expecting DC
which will make them chatter or buzz.


It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that it
would be easy for somebody that is more familiar with this type of equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA

"David Farber" wrote in message
...
snip
It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that it
would be easy for somebody that is more familiar with this type of
equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA

These relays are all designed to be energized by an AC source. The copper
shunt at the end of the pole piece is characteristic of AC relays. Is there
a 24 volt transformer anywhere in there and do all of the relays chatter, or
just one?

David

"David" wrote in message
et...

"David Farber" wrote in message
...
snip
It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that it
would be easy for somebody that is more familiar with this type of
equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA

These relays are all designed to be energized by an AC source. The copper
shunt at the end of the pole piece is characteristic of AC relays. Is
there
a 24 volt transformer anywhere in there and do all of the relays chatter,
or
just one?

David


Yes, there is a 24V transformer. The difficult part is figuring out which
one(s) are chattering. They are not in a very convenient place to observe
what's going on and all three of them are mounted side by side. I might need
to extend the wires a bit so they can be moved into plain view and still
have them electrically connected. Can you please explain in the picture of
relay 1, http://www.pbase.com/mrfixit/image/81163240, what the rating of,
"120VAC/28VDC"means? Is that the rating of the contacts?

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

David Farber wrote:

"David" wrote in message
et...

"David Farber" wrote in message
...
snip

It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that it
would be easy for somebody that is more familiar with this type of
equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA


These relays are all designed to be energized by an AC source. The copper
shunt at the end of the pole piece is characteristic of AC relays. Is

there

a 24 volt transformer anywhere in there and do all of the relays chatter,

or

just one?

David



Yes, there is a 24V transformer. The difficult part is figuring out which
one(s) are chattering. They are not in a very convenient place to observe
what's going on and all three of them are mounted side by side. I might need
to extend the wires a bit so they can be moved into plain view and still
have them electrically connected. Can you please explain in the picture of
relay 1, http://www.pbase.com/mrfixit/image/81163240, what the rating of,
"120VAC/28VDC"means? Is that the rating of the contacts?

Thanks for your reply.
If you have a 24 volt supply then may I suggest you look for a rectifier
or diode that has shorted and sending 24 volt ac instead of DC to the coil.
those relays require DC volts if you're using voltages that low.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5

070620 1248 - David Farber posted:

This 28 year old Stanley Vemco automatic gate uses mechanical relays. The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can hear a
relay click with no problem, then the gate opens. Just before the gate is
fully open, it enables a sensor switch which interrupts power to the motor
relay. Then, you can hear one of the relays make a chattering noise which
decays in about two seconds. The same thing happens when the gate closes. It
seems to have gotten louder over the years. Since the entire circuit is AC,



Relays work on a magnetic principle. When voltage is applied to the coil,
the is created a magnetic circuit the engages. The magnetic pole pieces
slam together. If there is a piece of dirt, or other foreign substance on
the surface of the magnetic circuit where the pieces slam together, they
will not engage properly, and with AC, the magnet will chatter. This is
very annoying, and the poles should be cleaned. Just take a look in the
relay and clean out any debris that has fallen into the magnetic circuit.

"David Farber"
wrote in
message
...

"David" wrote
in message
et...

"David Farber"
wrote in
message
...
snip
It could also be due to, or
exacerbated by, a dried out
electrolytic
filter capacitor in the DC supply
circuitry.

It occurred to me that if I posted
the pictures of these relays, that
it
would be easy for somebody that is
more familiar with this type of
equipment
would be able to tell me if these
relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA

These relays are all designed to be
energized by an AC source. The copper
shunt at the end of the pole piece is
characteristic of AC relays. Is
there
a 24 volt transformer anywhere in
there and do all of the relays
chatter,
or
just one?

David


Yes, there is a 24V transformer. The
difficult part is figuring out which
one(s) are chattering. They are not in
a very convenient place to observe
what's going on and all three of them
are mounted side by side. I might need
to extend the wires a bit so they can
be moved into plain view and still
have them electrically connected. Can
you please explain in the picture of
relay 1,
http://www.pbase.com/mrfixit/image/81163240,
what the rating of,
"120VAC/28VDC"means? Is that the
rating of the contacts?

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA
The picture would indicate to me that
the contacts are rated for 11 amps with
either a 120v AC source a 28v DC source.
It is not obvious what the coil voltage
is supposed to be. Relay 2 appears to
have a 110vac coil and relay 3 a 24vac
coil.
These look remarkably clean for such an
old unit.

David

"Jamie" t wrote in message
...
David Farber wrote:

"David" wrote in message
et...

"David Farber" wrote in message
...
snip

It could also be due to, or exacerbated by, a dried out electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that
it
would be easy for somebody that is more familiar with this type of
equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA


These relays are all designed to be energized by an AC source. The
copper
shunt at the end of the pole piece is characteristic of AC relays. Is

there

a 24 volt transformer anywhere in there and do all of the relays
chatter,

or

just one?

David



Yes, there is a 24V transformer. The difficult part is figuring out
which
one(s) are chattering. They are not in a very convenient place to
observe
what's going on and all three of them are mounted side by side. I might
need
to extend the wires a bit so they can be moved into plain view and still
have them electrically connected. Can you please explain in the picture
of
relay 1, http://www.pbase.com/mrfixit/image/81163240, what the rating
of,
"120VAC/28VDC"means? Is that the rating of the contacts?

Thanks for your reply.
If you have a 24 volt supply then may I suggest you look for a rectifier
or diode that has shorted and sending 24 volt ac instead of DC to the
coil.
those relays require DC volts if you're using voltages that low.


--
"I'm never wrong, once i thought i was, but was mistaken"
Real Programmers Do things like this.
http://webpages.charter.net/jamie_5


As I found this unit, there is *no* dc power supply in this controller. One
relay coil is connected directly to the 120VAC line voltage and is always on
as long as the main power switch is on. All the other components are powered
by the 24VAC. Those components are the two remaining relays, one self
contained timer control device which delays the gate closing, and the
contactor, which has two 24ACV solenoids that activate switches to enable
the motor in either the forward or reverse direction.

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

"David" wrote in message
t...

"David Farber"
wrote in
message
...

"David" wrote
in message
et...

"David Farber"
wrote in
message
...
snip
It could also be due to, or
exacerbated by, a dried out
electrolytic
filter capacitor in the DC supply
circuitry.

It occurred to me that if I posted
the pictures of these relays, that
it
would be easy for somebody that is
more familiar with this type of
equipment
would be able to tell me if these
relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

http://www.pbase.com/mrfixit/image/81163242

http://www.pbase.com/mrfixit/image/81163244


Thanks for your reply.

--
David Farber
David Farber's Service Center
L.A., CA

These relays are all designed to be
energized by an AC source. The copper
shunt at the end of the pole piece is
characteristic of AC relays. Is
there
a 24 volt transformer anywhere in
there and do all of the relays
chatter,
or
just one?

David


Yes, there is a 24V transformer. The
difficult part is figuring out which
one(s) are chattering. They are not in
a very convenient place to observe
what's going on and all three of them
are mounted side by side. I might need
to extend the wires a bit so they can
be moved into plain view and still
have them electrically connected. Can
you please explain in the picture of
relay 1,
http://www.pbase.com/mrfixit/image/81163240,
what the rating of,
"120VAC/28VDC"means? Is that the
rating of the contacts?

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA
The picture would indicate to me that
the contacts are rated for 11 amps with
either a 120v AC source a 28v DC source.
It is not obvious what the coil voltage
is supposed to be. Relay 2 appears to
have a 110vac coil and relay 3 a 24vac
coil.
These look remarkably clean for such an
old unit.

David


The pictures are about two years old. The unit itself is located in a
protected box and that probably has helped to preserve the looks of the
components.

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

On Jun 20, 1:48 pm, "David Farber" wrote:
This 28 year old Stanley Vemco automatic gate uses mechanical relays. The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can hear a
relay click with no problem, then the gate opens. Just before the gate is
fully open, it enables a sensor switch which interrupts power to the motor
relay. Then, you can hear one of the relays make a chattering noise which
decays in about two seconds. The same thing happens when the gate closes. It
seems to have gotten louder over the years. Since the entire circuit is AC,

You've got a bad pair of contacts feeding the coil of one of the
relays. The chattering relay is probably not the one that is at
fault; the difficulty might well lie in that sensor switch. I've had
difficulties with magnetic reed switches in the past, and if there's
one there I would see about it. There may also be a bad connector
associated with the sensor switch. Find the wires that go to the
sensor switch and use a jumper across them to simulate the operation
of that switch. If the relays operate but do not chatter, then the
difficulty lies in the sensor switch or its wiring.

M Kinsler

"m kinsler" wrote in message
ps.com...
On Jun 20, 1:48 pm, "David Farber" wrote:
This 28 year old Stanley Vemco automatic gate uses mechanical relays.
The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can
hear a
relay click with no problem, then the gate opens. Just before the gate
is
fully open, it enables a sensor switch which interrupts power to the
motor
relay. Then, you can hear one of the relays make a chattering noise
which
decays in about two seconds. The same thing happens when the gate
closes. It
seems to have gotten louder over the years. Since the entire circuit is
AC,

You've got a bad pair of contacts feeding the coil of one of the
relays. The chattering relay is probably not the one that is at
fault; the difficulty might well lie in that sensor switch. I've had
difficulties with magnetic reed switches in the past, and if there's
one there I would see about it. There may also be a bad connector
associated with the sensor switch. Find the wires that go to the
sensor switch and use a jumper across them to simulate the operation
of that switch. If the relays operate but do not chatter, then the
difficulty lies in the sensor switch or its wiring.

M Kinsler


The sensor switches are regular microswitches. I'll do the jumper test and
see what happens.

Thanks for the good suggestion.

--
David Farber
David Farber's Service Center
L.A., CA

On Mon, 25 Jun 2007 15:48:38 -0700, "David Farber"
wrote:


"Ross Herbert" wrote in message
.. .
On Fri, 22 Jun 2007 17:47:11 GMT, "James Sweet"
wrote:


wrote in message
roups.com...
On Jun 21, 2:53 pm, "David Farber"
wrote:

Sorry about this incomplete message. It was erroneously sent. I
think the
solution will be to replace the noisy relays with new ones.

That, it would. Stanley makes (made) good stuff, and 28 years
ain't
nohow half-bad. If all it is is relays, count yourself lucky.

Peter Wieck
Wyncote, PA


Might be worth checking to see if there's a diode or rectifier
bridge
in
there. A shorted diode could cause AC to be fed to relay coils
expecting DC
which will make them chatter or buzz.


It could also be due to, or exacerbated by, a dried out
electrolytic
filter capacitor in the DC supply circuitry.

It occurred to me that if I posted the pictures of these relays, that
it
would be easy for somebody that is more familiar with this type of
equipment
would be able to tell me if these relays have AC or DC type coils:

http://www.pbase.com/mrfixit/image/81163240

The contact appears to be in good condition at least.
Can't tell from the text whether it is AC or DC coil. The details
appear to show the contact ratings only. Anything written on the other
side of the coil?


http://www.pbase.com/mrfixit/image/81163242


Midtex 1522T200 - Online Components
http://www.onlinecomponents.com/product/3123033
Appears to be 120V ac coil.


http://www.pbase.com/mrfixit/image/81163244

Midtex 15523Q200 - Online Components
http://www.onlinecomponents.com/product/3123040
Appears to be 24V ac coil

Midtex is now part of the Tyco brand stable but I can't locate the
part numbers on their site. Have requested specifications from Tyco if
available. Will post result.

On Wed, 27 Jun 2007 07:39:10 GMT, Ross Herbert
wrote:


http://www.pbase.com/mrfixit/image/81163242


Midtex 15522T200 - Online Components
http://www.onlinecomponents.com/product/3123033
Appears to be 120V ac coil.


http://www.pbase.com/mrfixit/image/81163244

Midtex 15523Q200 - Online Components
http://www.onlinecomponents.com/product/3123040
Appears to be 24V ac coil

Midtex is now part of the Tyco brand stable but I can't locate the
part numbers on their site. Have requested specifications from Tyco
if available. Will post result.


PS. Since you say there is no DC power supply then it would appear
that photo 1 also shows an ac coil relay.

"Ross Herbert" wrote in message
...
On Wed, 27 Jun 2007 07:39:10 GMT, Ross Herbert
wrote:


http://www.pbase.com/mrfixit/image/81163242


Midtex 15522T200 - Online Components
http://www.onlinecomponents.com/product/3123033
Appears to be 120V ac coil.


http://www.pbase.com/mrfixit/image/81163244

Midtex 15523Q200 - Online Components
http://www.onlinecomponents.com/product/3123040
Appears to be 24V ac coil

Midtex is now part of the Tyco brand stable but I can't locate the
part numbers on their site. Have requested specifications from Tyco
if available. Will post result.


PS. Since you say there is no DC power supply then it would appear
that photo 1 also shows an ac coil relay.

Perhaps whoever worked on it before was replacing parts and not too picky
about what types of relays were put in.

I have uploaded a schematic of the electronics which I drew from tracing all
the wires. I'd like to know if anybody can find any mistakes in the wiring
diagram.

http://www.pbase.com/image/81266775

Secondly, there is a bell hose that opens the gate from the inside of the
garage and a key that opens the gate from the outside. There is a second
hose whose sensor is not hooked up which runs underneath the gate when in
the closed position. I think this is a safety factor in case somebody drives
in and the gate starts to close and would prefer not having their car
smashed. As a security precaution, I think it would be smart to have this
second hose sensor only allowed to be activated if the gate is actually
closing. Where would be the correct spot, assuming one exists, to insert the
second hose sensor that would *only* open the gate if the gate is in the
process of closing?

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

On Wed, 27 Jun 2007 11:38:15 -0700, "David Farber"
wrote:


"Ross Herbert" wrote in message
.. .
On Wed, 27 Jun 2007 07:39:10 GMT, Ross Herbert
wrote:


http://www.pbase.com/mrfixit/image/81163242


Midtex 15522T200 - Online Components
http://www.onlinecomponents.com/product/3123033
Appears to be 120V ac coil.


http://www.pbase.com/mrfixit/image/81163244

Midtex 15523Q200 - Online Components
http://www.onlinecomponents.com/product/3123040
Appears to be 24V ac coil

Midtex is now part of the Tyco brand stable but I can't locate the
part numbers on their site. Have requested specifications from
Tyco
if available. Will post result.


PS. Since you say there is no DC power supply then it would appear
that photo 1 also shows an ac coil relay.

Perhaps whoever worked on it before was replacing parts and not too
picky
about what types of relays were put in.

I have uploaded a schematic of the electronics which I drew from
tracing all
the wires. I'd like to know if anybody can find any mistakes in the
wiring
diagram.

http://www.pbase.com/image/81266775

Secondly, there is a bell hose that opens the gate from the inside of
the
garage and a key that opens the gate from the outside. There is a
second
hose whose sensor is not hooked up which runs underneath the gate
when in
the closed position. I think this is a safety factor in case somebody
drives
in and the gate starts to close and would prefer not having their car
smashed. As a security precaution, I think it would be smart to have
this
second hose sensor only allowed to be activated if the gate is
actually
closing. Where would be the correct spot, assuming one exists, to
insert the
second hose sensor that would *only* open the gate if the gate is in
the
process of closing?

Thanks for your reply.


Yipes! All those uninsulated terminals look dangerous to me....

Drawing out schematics of relay equipment is an art in itself. You
have to establish conventions (ie, moving and stationary contact sets,
coil relationships and status of the total mechanism). You must draw
the whole system when it is in a defined state, such as "gate closed",
and then draw the state of each relay and its associated contacts in
this condition, remembering that the moving and stationary contact
springs must also be drawn to reflect the associated relay situation.

For example your notes say that Relay A is shown de-activated but the
schematic is drawn such that its coil IS activated via the limit close
switch (ie. the gate is closed). Also, the schematic shows the timer
relay is activated from GND at C/9-3 (deactivated) via A/8-3
(deactivated) to 24Vac, yet the timer relay contact is shown as being
open.

The schematic also shows the main power switch is ON and the B relay
is activated. I assume those B contacts are supposed to be normally
open when the relay is deactivated, so if this assumption is correct
and the relay is drawn in its activated position, then the contacts
should be drawn with the moving contact at the top being pulled
towards the coil and making contact with the stationary contact. As
drawn the contacts are shown as opening when the coil is activated but
I assume you meant to draw it with the contacts making when the coil
is activated.

Also, where is the motor connected and what voltage supply powers the
motor?

Unless you can clearly define the status and show things as they
really are in that condition, then it is difficult to work out how
things are meant to work.

Having said that, your first effort is to be commended, considering
you probably haven't had to do this sort of thing before.

"Ross Herbert" wrote in message
...
On Wed, 27 Jun 2007 11:38:15 -0700, "David Farber"
wrote:


"Ross Herbert" wrote in message
.. .
On Wed, 27 Jun 2007 07:39:10 GMT, Ross Herbert
wrote:


http://www.pbase.com/mrfixit/image/81163242


Midtex 15522T200 - Online Components
http://www.onlinecomponents.com/product/3123033
Appears to be 120V ac coil.


http://www.pbase.com/mrfixit/image/81163244

Midtex 15523Q200 - Online Components
http://www.onlinecomponents.com/product/3123040
Appears to be 24V ac coil

Midtex is now part of the Tyco brand stable but I can't locate the
part numbers on their site. Have requested specifications from
Tyco
if available. Will post result.


PS. Since you say there is no DC power supply then it would appear
that photo 1 also shows an ac coil relay.

Perhaps whoever worked on it before was replacing parts and not too
picky
about what types of relays were put in.

I have uploaded a schematic of the electronics which I drew from
tracing all
the wires. I'd like to know if anybody can find any mistakes in the
wiring
diagram.

http://www.pbase.com/image/81266775

Secondly, there is a bell hose that opens the gate from the inside of
the
garage and a key that opens the gate from the outside. There is a
second
hose whose sensor is not hooked up which runs underneath the gate
when in
the closed position. I think this is a safety factor in case somebody
drives
in and the gate starts to close and would prefer not having their car
smashed. As a security precaution, I think it would be smart to have
this
second hose sensor only allowed to be activated if the gate is
actually
closing. Where would be the correct spot, assuming one exists, to
insert the
second hose sensor that would *only* open the gate if the gate is in
the
process of closing?

Thanks for your reply.


Yipes! All those uninsulated terminals look dangerous to me....

Drawing out schematics of relay equipment is an art in itself. You
have to establish conventions (ie, moving and stationary contact sets,
coil relationships and status of the total mechanism). You must draw
the whole system when it is in a defined state, such as "gate closed",
and then draw the state of each relay and its associated contacts in
this condition, remembering that the moving and stationary contact
springs must also be drawn to reflect the associated relay situation.

For example your notes say that Relay A is shown de-activated but the
schematic is drawn such that its coil IS activated via the limit close
switch (ie. the gate is closed). Also, the schematic shows the timer
relay is activated from GND at C/9-3 (deactivated) via A/8-3
(deactivated) to 24Vac, yet the timer relay contact is shown as being
open.

The schematic also shows the main power switch is ON and the B relay
is activated. I assume those B contacts are supposed to be normally
open when the relay is deactivated, so if this assumption is correct
and the relay is drawn in its activated position, then the contacts
should be drawn with the moving contact at the top being pulled
towards the coil and making contact with the stationary contact. As
drawn the contacts are shown as opening when the coil is activated but
I assume you meant to draw it with the contacts making when the coil
is activated.

Also, where is the motor connected and what voltage supply powers the
motor?

Unless you can clearly define the status and show things as they
really are in that condition, then it is difficult to work out how
things are meant to work.

Having said that, your first effort is to be commended, considering
you probably haven't had to do this sort of thing before.

I haven't had to do this thing before. I don't envy the people that have to
do this either.

I had another look at the box last night. I removed the three relays from
their mounting plate to see if I could isolate the chattering. It turned out
the relay which I thought was always on, relay b in the schematic, is not
always on. It's only on when the gate is stationary. I've revised the
schematic, http://www.pbase.com/image/81318340 and also used your advice to
make the descriptions at the top of the schematic actually match what is
shown.

The motor is driven by 240VAC which does not enter the controller part of
the gate. However I did notice that whatever is switching relay b on and
off, is coming from one of the four wires (not shown) coming from the motor.
Eventually I'll have to figure that into the drawing as well.

The question now is what is the circuit path that keeps the closing
coil/solenoid energized once the gate starts to close and relay b is turned
off? I have certainly missed something in translating the actually wiring to
the schematic drawing.

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA

"m kinsler" wrote in message
ps.com...
On Jun 20, 1:48 pm, "David Farber" wrote:
This 28 year old Stanley Vemco automatic gate uses mechanical relays.
The
problem is that the relays are noisy when either the opening or closing
sensor switches are activated at the end of its travel. For example,
somebody runs over the air hose to begin the open operation. You can
hear a
relay click with no problem, then the gate opens. Just before the gate
is
fully open, it enables a sensor switch which interrupts power to the
motor
relay. Then, you can hear one of the relays make a chattering noise
which
decays in about two seconds. The same thing happens when the gate
closes. It
seems to have gotten louder over the years. Since the entire circuit is
AC,

You've got a bad pair of contacts feeding the coil of one of the
relays. The chattering relay is probably not the one that is at
fault; the difficulty might well lie in that sensor switch. I've had
difficulties with magnetic reed switches in the past, and if there's
one there I would see about it. There may also be a bad connector
associated with the sensor switch. Find the wires that go to the
sensor switch and use a jumper across them to simulate the operation
of that switch. If the relays operate but do not chatter, then the
difficulty lies in the sensor switch or its wiring.

M Kinsler


Now that I've added the motor circuits to the schematic, you will notice
that the coil in the B relay is in series with what looks suspiciously like
a motor start capacitor. Can this be correct?

http://www.pbase.com/image/81471200

Thanks for your reply.
--
David Farber
David Farber's Service Center
L.A., CA