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Default 440 volt three phase question

In article , John Grabowski wrote:
*As I recall on a delta connection one of the phases will have a higher
reading to ground than the other two. On a Y connection the reading to
ground will be the same. In NJ, Public Service Electric and Gas will not
permit that high leg to be installed in the same panel as the neutral.
The NEC allows it though.

What you are describing sounds to me like a 240V "star" system with high
leg, a variant of Y. Two of the phases are 240V center tap with the
center
tap connected to neutral. That provides four 120V legs. The third is
240V
with one end rather than the center tap of that transformer's winding
connected to neutral to provide the "high leg". It is possible to use
the
center tap of that to provide a fifth 120V leg.



*It's been a while since I have worked on three phase, but I seem to
recall on a three phase 240 volt delta system, the high (Orange) leg is
around 180 volts to ground. I only remember one phase as being center
tapped. Next time I meet with someone from the power company I will ask
them to refresh my memory.


*I was just looking in my PSE&G handbook and found a drawing for three phase
services. They supply 3 phase 4 wire 120/240 volt delta,


Is that someting newer to me, as in 2 legs 120V from neutral and one leg
208V from neutral?

3 phase 4 wire 120/208 volt wye,


No 240V here. That one is good for loads 120V from any of the 3 phases
to ground, as well as 208V delta loads.

3 phase 4 wire 277/480 volt wye services


That one appears to me to be a little common. That one gets to power
460-480 volt industrial motor loads and loads downstream of of step-down
transformers downstream of the industrial customer's electic meter for
120V needs.

For one thing, I have noticed recent presence of fluorescent lamp
ballasts rated for 277V or 120-277 V as well as recent avilability of 277V
incandescent lamps from bulbs.com.

and they also
list 3 phase 4 wire 265/460 volt wye but in parentheses they have
"Obsolete".


My guess is that's 4x 115V while more-usual is 4x 120V, for
phase-to-phase.

I guess the 460 is being or has been phased out (No pun
intended). For the delta service they want the orange leg on the right
terminal in the meter and of course after that it must go on the center
terminal as per the NEC. As I mentioned before PSE&G wants the neutral in a
separate panel from the high leg, therefore two panels must be installed;
one single phase with neutral and one three phase without neutral. I think
JCP&L will accept the neutral and high leg together, but I would have to
double check.


--
- Don Klipstein (Jr) )
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Default 440 volt three phase question

On 5/29/2010 6:29 PM, Don Klipstein wrote:
In , John Grabowski wrote:

*As I recall on a delta connection one of the phases will have a higher
reading to ground than the other two. On a Y connection the reading to
ground will be the same. In NJ, Public Service Electric and Gas will not
permit that high leg to be installed in the same panel as the neutral.
The NEC allows it though.


What you are describing sounds to me like a 240V "star" system with high
leg, a variant of Y. Two of the phases are 240V center tap with the center
tap connected to neutral. That provides four 120V legs. The third is 240V
with one end rather than the center tap of that transformer's winding
connected to neutral to provide the "high leg". It is possible to use the
center tap of that to provide a fifth 120V leg.


The secondaries are connected in delta. One of the secondaries has a CT
that is used as the neutral for 120 VAC loads.
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Default 440 volt three phase question

On 5/30/2010 3:25 AM, harry wrote:
On May 29, 7:52�pm, wrote:
On 5/29/2010 11:08 AM, harry wrote:





On May 29, 12:32 pm, �wrote:
On 5/29/2010 3:14 AM, harry wrote:


On May 28, 10:55 pm, � wrote:
On 5/28/2010 3:44 PM, harry wrote:


On May 28, 6:31 pm, Tom � wrote:
On May 27, 5:22 pm, "Stormin Mormon"


� wrote:
Oh, thank you. I didn't know.


--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


� wrote in message


...


No, it's 220 more or less, to ground


It is entirely possible that the 440 volts is from a delta configured
transformer that is not ground referenced or is corner grounded.
Point is that one shouldn't assume that the transformer that is
supplying the current is Y configured.
--
Tom Horne


It's only possible to determine how a three phase transformer is
connected visually. Ie by checking the connections.


You can make a very reliable determination with just a meter and knowing
how 3 phase AC works.- Hide quoted text -


- Show quoted text -


That is completely wrong.


Really? So if we take the original question where the OP could have used
their meter and as an example observed 480 VAC between each phase leg
and 277 from each phase leg to neutral we couldn't declare with
confidence that the source transformers were connected in "Y" ?- Hide quoted text -


- Show quoted text -


If you read my post, If there are just three line �connections brought
out, no, you can't tell whether its "star" or "delta" connected.


I did. You didn't describe that limitation but you could still be a long
way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one of
the meter probes on ground.- Hide quoted text -

- Show quoted text -


But you still wouldn't know whether it was star or delta connected.


Consider the readings you would get if it were one or the other.
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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

--
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Learn more about Jesus
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"harry" wrote in message
...


- Show quoted text -


That is completely wrong.


Really? So if we take the original question where the OP could have
used
their meter and as an example observed 480 VAC between each phase
leg
and 277 from each phase leg to neutral we couldn't declare with
confidence that the source transformers were connected in "Y" ?-
Hide quoted text -

- Show quoted text -


If you read my post, If there are just three line connections brought
out, no, you can't tell whether its "star" or "delta" connected.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.



--
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Learn more about Jesus
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..


"George" wrote in message
...
On 5/29/2010 11:08 AM, harry wrote:
On May 29, 12:32�pm, wrote:
On 5/29/2010 3:14 AM, harry wrote:


If you read my post, If there are just three line connections
brought
out, no, you can't tell whether its "star" or "delta" connected.


I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one
of
the meter probes on ground.




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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Sounds like, no.

--
Christopher A. Young
Learn more about Jesus
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..


"Don Klipstein" wrote in message
...
In article , George wrote:
On 5/29/2010 11:08 AM, harry wrote:
and 277 from each phase leg to neutral we couldn't declare with
confidence that the source transformers were connected in "Y" ?-
Hide quoted text -

- Show quoted text -


If you read my post, If there are just three line connections
brought
out, no, you can't tell whether its "star" or "delta" connected.


I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one
of
the meter probes on ground.


It sounds easy enough for a 440V delta circuit to have all 3 legs
measure 277 volts from ground. One way for that to happen is if there
is
significant and equal stray capacitance from each leg to ground.
Another
is if someone connects a "Y" load to the circuit, and connects the
load's
center point to ground.

--
- Don Klipstein )


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Default 440 volt three phase question

In this particular instance, the maint people (mall management) didn't
know there was a roof ladder. How would they know the voltage of a
device?

--
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Learn more about Jesus
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"Metspitzer" wrote in message
...

I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one
of
the meter probes on ground.


If I was unsure of the voltage, what I would do is call maintenance
and ask.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Hmm. Maybe need a transformer, then?

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"George" wrote in message
...

*As I recall on a delta connection one of the phases will have a
higher
reading to ground than the other two. On a Y connection the reading
to
ground will be the same. In NJ, Public Service Electric and Gas will
not
permit that high leg to be installed in the same panel as the
neutral.
The NEC allows it though.


That is because of the way the power company arranges that type of
service. One of the transformers used in the delta connection has a
center tap. They did that it situations where most of the load would
be
3 phase but the same service could still supply 120 general purpose
loads without the need for an on premise transformer.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Will a volt meter tell me if a transformer would help?

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"John Grabowski" wrote in message
...

That is because of the way the power company arranges that type of
service. One of the transformers used in the delta connection has a
center
tap. They did that it situations where most of the load would be 3
phase
but the same service could still supply 120 general purpose loads
without
the need for an on premise transformer.




*So a volt meter will tell you if the service is a delta or a Y.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

I can usually get a 120 volt device to run from 220 VAC single phase.

--
Christopher A. Young
Learn more about Jesus
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..


"Don Klipstein" wrote in message
...
In article , John Grabowski wrote:

*As I recall on a delta connection one of the phases will have a
higher
reading to ground than the other two. On a Y connection the reading
to
ground will be the same. In NJ, Public Service Electric and Gas will
not
permit that high leg to be installed in the same panel as the
neutral.
The NEC allows it though.


What you are describing sounds to me like a 240V "star" system with
high
leg, a variant of Y. Two of the phases are 240V center tap with the
center
tap connected to neutral. That provides four 120V legs. The third is
240V
with one end rather than the center tap of that transformer's winding
connected to neutral to provide the "high leg". It is possible to use
the
center tap of that to provide a fifth 120V leg.

--
- Don Klipstein )




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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Please ask the power co person if it's possible to run a 120 volt
device.

--
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Learn more about Jesus
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..


"John Grabowski" wrote in message
...

What you are describing sounds to me like a 240V "star" system with
high
leg, a variant of Y. Two of the phases are 240V center tap with the
center
tap connected to neutral. That provides four 120V legs. The third
is
240V
with one end rather than the center tap of that transformer's
winding
connected to neutral to provide the "high leg". It is possible to
use the
center tap of that to provide a fifth 120V leg.



*It's been a while since I have worked on three phase, but I seem to
recall
on a three phase 240 volt delta system, the high (Orange) leg is
around 180
volts to ground. I only remember one phase as being center tapped.
Next
time I meet with someone from the power company I will ask them to
refresh
my memory.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Would that run a vacuum cleaner?

--
Christopher A. Young
Learn more about Jesus
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"John Grabowski" wrote in message
...


*It's been a while since I have worked on three phase, but I seem to
recall on a three phase 240 volt delta system, the high (Orange) leg
is
around 180 volts to ground. I only remember one phase as being
center
tapped. Next time I meet with someone from the power company I will
ask
them to refresh my memory.



*I was just looking in my PSE&G handbook and found a drawing for three
phase
services. They supply 3 phase 4 wire 120/240 volt delta, 3 phase 4
wire
120/208 volt wye, 3 phase 4 wire 277/480 volt wye services and they
also
list 3 phase 4 wire 265/460 volt wye but in parentheses they have
"Obsolete". I guess the 460 is being or has been phased out (No pun
intended). For the delta service they want the orange leg on the
right
terminal in the meter and of course after that it must go on the
center
terminal as per the NEC. As I mentioned before PSE&G wants the
neutral in a
separate panel from the high leg, therefore two panels must be
installed;
one single phase with neutral and one three phase without neutral. I
think
JCP&L will accept the neutral and high leg together, but I would have
to
double check.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Long as it runs a vacuum cleaner.

--
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Learn more about Jesus
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..


"harry" wrote in message
...

I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access
to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing
one of
the meter probes on ground.- Hide quoted text -

- Show quoted text -


But you still wouldn't know whether it was star or delta connected.


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Default 440 volt three phase question

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Would it run a vacuum cleaner?

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"George" wrote in message
...
On 5/30/2010 3:25 AM, harry wrote:


I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access
to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing
one of
the meter probes on ground.- Hide quoted text -

- Show quoted text -


But you still wouldn't know whether it was star or delta connected.


Consider the readings you would get if it were one or the other.


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Default 440 volt three phase question


The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.



*No Chris. At 440 volts one leg to ground would be way over 200 volts. As
you said there should be a 120 volt service receptacle within 50'. That
requirement has been in the mechanical code before it made it into the
electrical code.



- Show quoted text -


That is completely wrong.


Really? So if we take the original question where the OP could have
used
their meter and as an example observed 480 VAC between each phase
leg
and 277 from each phase leg to neutral we couldn't declare with
confidence that the source transformers were connected in "Y" ?-
Hide quoted text -

- Show quoted text -


If you read my post, If there are just three line connections brought
out, no, you can't tell whether its "star" or "delta" connected.





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Default 440 volt three phase question

On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Will a volt meter tell me if a transformer would help?


Sure, any particular reason why you insist on top posting in a newsgroup
where 99% of the posts are bottom posted? Just plain old politeness says
you "go with the flow". If you were in a crowded hallway and everyone
was walking to the right would you walk on the left just to prove something?
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Default 440 volt three phase question

In article ,
George wrote:

On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Will a volt meter tell me if a transformer would help?


Sure, any particular reason why you insist on top posting in a newsgroup
where 99% of the posts are bottom posted? Just plain old politeness says
you "go with the flow". If you were in a crowded hallway and everyone
was walking to the right would you walk on the left just to prove something?


An issue that Chris refuses to discuss, other than to trot out the
ridiculous "I don't like to scroll" argument that top-posters favor,
completely ignoring the fact that his own top-posting saves him no
scrolling. FWIW, I did once ask him if it was Brigham Young who first
advocated top posting, and he said no, it was Joseph Smith.
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Default 440 volt three phase question

In article , George wrote:
On 5/29/2010 6:29 PM, Don Klipstein wrote:
In , John Grabowski wrote:

*As I recall on a delta connection one of the phases will have a higher
reading to ground than the other two. On a Y connection the reading to
ground will be the same. In NJ, Public Service Electric and Gas will not
permit that high leg to be installed in the same panel as the neutral.
The NEC allows it though.


What you are describing sounds to me like a 240V "star" system with high
leg, a variant of Y. Two of the phases are 240V center tap with the center
tap connected to neutral. That provides four 120V legs. The third is 240V
with one end rather than the center tap of that transformer's winding
connected to neutral to provide the "high leg". It is possible to use the
center tap of that to provide a fifth 120V leg.


The secondaries are connected in delta. One of the secondaries has a CT
that is used as the neutral for 120 VAC loads.


In that arrangement with 240V secondaries, there would be two legs that
are 120V from neutral and one that is 208V from neutral.

The situation that I experienced had a high leg 240V from neutral. That
made me think of another time when I once saw an outlet labelled 208V
3-phase (three lines 120V from ground in Y arrangement?).

--
- Don Klipstein )
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Default 440 volt three phase question

Thanks. That helps me refrain from frying a vacuum cleaner.

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"John Grabowski" wrote in message
...

The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.



*No Chris. At 440 volts one leg to ground would be way over 200
volts. As
you said there should be a 120 volt service receptacle within 50'.
That
requirement has been in the mechanical code before it made it into the
electrical code.



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Default 440 volt three phase question

Do you spend equal time, trying to reform people who leave a lot of
quoted text?

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"Smitty Two" wrote in message
news
An issue that Chris refuses to discuss, other than to trot out the
ridiculous "I don't like to scroll" argument that top-posters favor,
completely ignoring the fact that his own top-posting saves him no
scrolling. FWIW, I did once ask him if it was Brigham Young who first
advocated top posting, and he said no, it was Joseph Smith.




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Default 440 volt three phase question

On May 30, 12:40�pm, "Stormin Mormon"
wrote:
The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Would it run a vacuum cleaner?

--
Christopher A. Young
Learn more about Jesus
�www.lds.org
.

"George" wrote in message

...
On 5/30/2010 3:25 AM, harry wrote:



I did. You didn't describe that limitation but you could still be a
long
way from completely wrong with only a meter if you only had access
to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing
one of
the meter probes on ground.- Hide quoted text -


- Show quoted text -


But you still wouldn't know whether it was star or delta connected.


Consider the readings you would get if it were one or the other.


Look at the whole issue this way. Let's suppose you have an electric
circuit inside a box with two terminals.
You can measure the resistance of that circuit. For any given
frequency of a current you pass through it, you can measure the
impedance (XL or Xc).
And that's it. There's absolutely nothing else you can tell.
The same applies with a motor, transformer or whatever. If there are
more terminals, you can only determine resistance and impedance
between them.. Nothing whatever about the circuit inside the box.

It's down to Kirchhoffs laws. Read all about it.
http://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws

The bit about summation of currents at a node =0 is the bit you want.


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Default 440 volt three phase question

So, yes, it would run a vacuum cleaner?

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"harry" wrote in message
...


Look at the whole issue this way. Let's suppose you have an electric
circuit inside a box with two terminals.
You can measure the resistance of that circuit. For any given
frequency of a current you pass through it, you can measure the
impedance (XL or Xc).
And that's it. There's absolutely nothing else you can tell.
The same applies with a motor, transformer or whatever. If there are
more terminals, you can only determine resistance and impedance
between them.. Nothing whatever about the circuit inside the box.

It's down to Kirchhoffs laws. Read all about it.
http://en.wikipedia.org/wiki/Kirchhoff%27s_circuit_laws

The bit about summation of currents at a node =0 is the bit you want.



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Default 440 volt three phase question

On 5/30/2010 12:03 PM, Smitty Two wrote:
In ,
wrote:

On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to run a
device like a vacuum cleaner, or pressure washer.

Will a volt meter tell me if a transformer would help?


Sure, any particular reason why you insist on top posting in a newsgroup
where 99% of the posts are bottom posted? Just plain old politeness says
you "go with the flow". If you were in a crowded hallway and everyone
was walking to the right would you walk on the left just to prove something?


An issue that Chris refuses to discuss, other than to trot out the
ridiculous "I don't like to scroll" argument that top-posters favor,
completely ignoring the fact that his own top-posting saves him no
scrolling. FWIW, I did once ask him if it was Brigham Young who first
advocated top posting, and he said no, it was Joseph Smith.


And as I said it is a simple politeness thing. I participate in groups
where the norm for the group is top posting and I go with it because it
makes perfect sense for that situation.
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Default 440 volt three phase question

On May 29, 3:41*pm, (Don Klipstein) wrote:
In article , George wrote:
On 5/29/2010 11:08 AM, harry wrote:
On May 29, 12:32 pm, *wrote:
On 5/29/2010 3:14 AM, harry wrote:


On May 28, 10:55 pm, * wrote:
On 5/28/2010 3:44 PM, harry wrote:


On May 28, 6:31 pm, Tom * wrote:
On May 27, 5:22 pm, "Stormin Mormon"


* wrote:
Oh, thank you. I didn't know.


--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


* wrote in message


...


No, it's 220 more or less, to ground


It is entirely possible that the 440 volts is from a delta configured
transformer that is not ground referenced or is corner grounded.
Point is that one shouldn't assume that the transformer that is
supplying the current is Y configured.
--
Tom Horne


It's only possible to determine how a three phase transformer is
connected visually. Ie by checking the connections.


You can make a very reliable determination with just a meter and knowing
how 3 phase AC works.- Hide quoted text -


- Show quoted text -


That is completely wrong.


Really? So if we take the original question where the OP could have used
their meter and as an example observed 480 VAC between each phase leg
and 277 from each phase leg to neutral we couldn't declare with
confidence that the source transformers were connected in "Y" ?- Hide quoted text -


- Show quoted text -


If you read my post, If there are just three line *connections brought
out, no, you can't tell whether its "star" or "delta" connected.


I did. You didn't describe that limitation but you could still be a long
way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one of
the meter probes on ground.


* It sounds easy enough for a 440V delta circuit to have all 3 legs
measure 277 volts from ground. *One way for that to happen is if there is
significant and equal stray capacitance from each leg to ground. *Another
is if someone connects a "Y" load to the circuit, and connects the load's
center point to ground.

--
*- Don Klipstein )


Don
If the load had a "center point," i.e. if it is star configured, It
would create a ground fault that would either trip the ground detector
if present or just sit there until a fault occurred on another phase
were upon the completely different voltage will probably damage that
load.
--
Tom Horne
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Default 440 volt three phase question

In ,
Tom Horne wrote:

On May 29, 3:41*pm, (Don Klipstein) wrote:
In article , George wrote:


way from completely wrong with only a meter if you only had access to
the phase legs. Since a "Y" connection neutral is always bonded to
ground I could still get the same readings I described by placing one of
the meter probes on ground.


* It sounds easy enough for a 440V delta circuit to have all 3 legs
measure 277 volts from ground. *One way for that to happen is if there is
significant and equal stray capacitance from each leg to ground. *Another
is if someone connects a "Y" load to the circuit, and connects the load's
center point to ground.

*- Don Klipstein )


Don
If the load had a "center point," i.e. if it is star configured, It
would create a ground fault that would either trip the ground detector
if present or just sit there until a fault occurred on another phase
were upon the completely different voltage will probably damage that
load.


It surely appears to me that many old buildings lack ground fault
interruptors.

Thankfully, many, probably most buildings with 480V 3-phase are fed by
"Y" / "star" connected transformer secondaries. In which case, proper
neutrals are run (or at least are supposed to be). There is a common star
load in many of these buildings, often loading the 3 phases unequally:
277V lighting circuits.

--
- Don Klipstein )


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Bottom posting makes the reader scroll through old text to get at the
new. If a poster properly trims old text, the reader can scroll down
if s/he wants the context. A person who leaves four levels of
forwarding marks (like you did) is neglectful. Wasting others
bandwidth.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"harry" wrote in message
...
On May 31, 11:23�am, George wrote:
On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to
run a
device like a vacuum cleaner, or pressure washer.


Bottom posting enables the thread to be read consecutively and always
makes sense.


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Default 440 volt three phase question

On Jun 1, 1:16�pm, "Stormin Mormon"
wrote:
Bottom posting makes the reader scroll through old text to get at the
new. If a poster properly trims old text, the reader can scroll down
if s/he wants the context. A person who leaves four levels of
forwarding marks (like you did) is neglectful. �Wasting others
bandwidth.

--
Christopher A. Young
Learn more about Jesus
�www.lds.org
.

"harry" wrote in message

...
On May 31, 11:23 am, George wrote:

On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to
run a
device like a vacuum cleaner, or pressure washer.


Bottom posting enables the thread to be read consecutively and always
makes sense.


Not if there is to-ing and fro-ing on the topic. The whole continuity
is lost.
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Default 440 volt three phase question

In article , Stormin Mormon wrote:
Bottom posting makes the reader scroll through old text to get at the
new. If a poster properly trims old text, the reader can scroll down
if s/he wants the context. A person who leaves four levels of
forwarding marks (like you did) is neglectful. Wasting others
bandwidth.


I am posting "interleaved", second-place welcome to "bottom",
while "top" is "*at least* highly frowned upon" in Usenet. Even when
there is a fair rate of private e-mails being done in "top post manner".

Those who do what is expectable according to the societal norms of
Usenet quickly scroll past the lines of text beginning with quotation
symbols, even at expense of scrolling past and missing earlier ones
lacking quotation symbols.

"harry" wrote in message
...
On May 31, 11:23�am, George wrote:
On 5/30/2010 7:36 AM, Stormin Mormon wrote:
The OP question is if one leg to ground provides 120 volts to
run a
device like a vacuum cleaner, or pressure washer.


Bottom posting enables the thread to be read consecutively and always
makes sense.


In the case of Usenet as opposed to some "private e-mail cultures",
I say "amen to amen-at-least-squared"!
--
- Don Klipstein )
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Default OT 440 volt three phase question

Didn't Hitler try to make everyone live by his rules ? Stormey gives me
the impression he is always right.
He should keep his preeeeeeeching for Saturday and not tell every one
how to live their lives.
Jerry


http://community.webtv.net/awoodbutc...oodWorkingPage



http://community.webtv.net/awoodbutcher/1974RuppCentair

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Default 440 volt three phase question

On Thursday, May 27, 2010 at 10:03:40 AM UTC-5, Stormin Mormon wrote:
I've had the moment to work on 440 volt roof top heating and AC.

Once in a while, need some power to run a 120 volt device. Is it 120
volts from one leg to ground?

(Yeah, I could just check it. But I was on the roof yesterday, and not
sure how long until I get to another roof.)

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


I've got a client looking to buy 50 - 100 acres with access to 440 3 phase electricity. Question 1 - is this a heavy electric capacity? 2 - How does one figure this information out. There are power poles that traverse the frontage of the property. There are 4 wires total on the poles. One of the poles has 3 transformers on it. Any idea?


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On Mon, 23 Apr 2018 13:54:22 -0700 (PDT), wrote:

On Thursday, May 27, 2010 at 10:03:40 AM UTC-5, Stormin Mormon wrote:
I've had the moment to work on 440 volt roof top heating and AC.

Once in a while, need some power to run a 120 volt device. Is it 120
volts from one leg to ground?

(Yeah, I could just check it. But I was on the roof yesterday, and not
sure how long until I get to another roof.)

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


I've got a client looking to buy 50 - 100 acres with access to 440 3 phase electricity. Question 1 - is this a heavy electric capacity? 2 - How does one figure this information out. There are power poles that traverse the frontage of the property. There are 4 wires total on the poles. One of the poles has 3 transformers on it. Any idea?


480v will usually be wye distribution and that is 277v to ground. You
will need a transformer to get 120/240 but they are readily available.
That is generally considered a "heavy" service
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.


I've got a client looking to buy 50 - 100 acres
with access to 440 3 phase electricity.
Question 1 - is this a heavy electric capacity?
2 - How does one figure this information out.
There are power poles that traverse the frontage of the property.
There are 4 wires total on the poles.
One of the poles has 3 transformers on it. Any idea?



The four wires on the pole are 3 phase power + neutral.
If the 3 cans on the pole are indeed step-down transformers
you will see that they supply a service to nearby customers.
they could be regulating transformers or reclosers ?
If you look for the nearest major customer supplied from the
line - it might give you a starting point to ask the power company
about that line's capability and connection costs.
If your client is considering feeding back into the grid
with his wind or solar generation - it would require some extra
approvals and installation costs.
John T.

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Default 440 volt three phase question

On Monday, April 23, 2018 at 5:08:44 PM UTC-4, wrote:
On Mon, 23 Apr 2018 13:54:22 -0700 (PDT), wrote:

On Thursday, May 27, 2010 at 10:03:40 AM UTC-5, Stormin Mormon wrote:
I've had the moment to work on 440 volt roof top heating and AC.

Once in a while, need some power to run a 120 volt device. Is it 120
volts from one leg to ground?

(Yeah, I could just check it. But I was on the roof yesterday, and not
sure how long until I get to another roof.)

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


I've got a client looking to buy 50 - 100 acres with access to 440 3 phase electricity. Question 1 - is this a heavy electric capacity? 2 - How does one figure this information out. There are power poles that traverse the frontage of the property. There are 4 wires total on the poles. One of the poles has 3 transformers on it. Any idea?


480v will usually be wye distribution and that is 277v to ground. You
will need a transformer to get 120/240 but they are readily available.
That is generally considered a "heavy" service


What's missing is what's the objective, eg do they need 3 phase or just
240/120 for a house.
How the cost to you is determined is probably going to vary greatly
depending on the policy of the local utility and their costs. A call
to the power company having the distances, whether it;s to be overhead
or underground, what kind of service you want, eg 300A 240/120 splitphase
or 3 phase, etc should produce some numbers.
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wrote in message
...
On Thursday, May 27, 2010 at 10:03:40 AM UTC-5, Stormin Mormon wrote:
I've had the moment to work on 440 volt roof top heating and AC.

Once in a while, need some power to run a 120 volt device. Is it 120
volts from one leg to ground?

(Yeah, I could just check it. But I was on the roof yesterday, and not
sure how long until I get to another roof.)

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


I've got a client looking to buy 50 - 100 acres with access to 440 3 phase
electricity. Question 1 - is this a heavy electric capacity? 2 - How does
one figure this information out. There are power poles that traverse the
frontage of the property. There are 4 wires total on the poles. One of the
poles has 3 transformers on it. Any idea?


Very disturbing post as Stormin died on a roof 2 years ago and cannot reply.






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Default 440 volt three phase question

In article , says...

wrote in message
...
On Thursday, May 27, 2010 at 10:03:40 AM UTC-5, Stormin Mormon wrote:
I've had the moment to work on 440 volt roof top heating and AC.

Once in a while, need some power to run a 120 volt device. Is it 120
volts from one leg to ground?

(Yeah, I could just check it. But I was on the roof yesterday, and not
sure how long until I get to another roof.)

--
Christopher A. Young
Learn more about Jesus
www.lds.org
.


I've got a client looking to buy 50 - 100 acres with access to 440 3 phase
electricity. Question 1 - is this a heavy electric capacity? 2 - How does
one figure this information out. There are power poles that traverse the
frontage of the property. There are 4 wires total on the poles. One of the
poles has 3 transformers on it. Any idea?


Very disturbing post as Stormin died on a roof 2 years ago and cannot reply.






Yea, I never look at the dates. See that was written over 7 years ago.

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