My shop addition (21'x60' added on to an existing 40'x60') is coming along.
Had to let go of my electrician due to the fact that he never shows up etc.
He installed a new 3-phase service entrance. From said entrance we are
feeding a sub-panel to the old shop. This subpanel is single phase 100 amp.

I am to install a second 50 amp 3 phase sub-panel to another section of the
new shop. My question is wiring for the run to the sub-panel. I purchase
some 3-#6 wire (52' run). This is 3 #6's and a ground wire. 4 wires total.
Out of this 3-phase sub, I will be running circuits for my wife's kilns
(220v), my 3-phase machines and a few 20 amp (120v) plug circuits. I am
confused about the 120 volt circuits. Being that I only have 4 wires (3
current, one ground), how do I run a neutral wire to these circuits. Even
more confusing is that the neutral and the ground all run to the same bus
bar, so what is the difference?

I can give up my investment in the 52' of 6-3 cable, but I can't seem to
find any 6-4 wire (4-#6's, plus ground), at least not at any one of the
home clubs. I could simply add a fourth wire (white neutral) to the 3 phase
sub-panel, where it will simply be bonded with the ground. Or, I could
simply create a neutral by bonding to the ground in the sub-panel and not
run a fifth wire. All very confusing.

Any and all advice appreciated. BTW, I do have on older copy of the
National Electric Code, but can't seem to find the answer therein.

Thanks, Ivan Vegvary

"Ivan Vegvary" wrote in message
...
My shop addition (21'x60' added on to an existing 40'x60') is coming
along.
Had to let go of my electrician due to the fact that he never shows up
etc.
He installed a new 3-phase service entrance. From said entrance we are
feeding a sub-panel to the old shop. This subpanel is single phase 100
amp.

I am to install a second 50 amp 3 phase sub-panel to another section of
the
new shop. My question is wiring for the run to the sub-panel. I purchase
some 3-#6 wire (52' run). This is 3 #6's and a ground wire. 4 wires
total.
Out of this 3-phase sub, I will be running circuits for my wife's kilns
(220v), my 3-phase machines and a few 20 amp (120v) plug circuits.


No you won't you need 5 wires and a "Y" 4 wire + ground box for the
subpanel, if you plan on any 120 volt circuits. You nay be able to get a
isolated neutral bus for your delta box from its manufacture and a new label
to put on it so the inspector will approve it

I am
confused about the 120 volt circuits. Being that I only have 4 wires (3
current, one ground), how do I run a neutral wire to these circuits. Even
more confusing is that the neutral and the ground all run to the same bus
bar, so what is the difference?

If you are confused about this, I suggest that you hire another electrician
to finish up the job.
In your case the ONLY place the grounding conductor and the grounded
conductor are to be bonded is at the service entrance.


I can give up my investment in the 52' of 6-3 cable, but I can't seem to
find any 6-4 wire (4-#6's, plus ground), at least not at any one of the
home clubs. I could simply add a fourth wire (white neutral) to the 3
phase
sub-panel, where it will simply be bonded with the ground. Or, I could
simply create a neutral by bonding to the ground in the sub-panel and not
run a fifth wire. All very confusing.

Any and all advice appreciated. BTW, I do have on older copy of the
National Electric Code, but can't seem to find the answer therein.

Thanks, Ivan Vegvary

On Mon, 26 Jul 2004 04:53:58 GMT, "Ivan Vegvary" wrote:
My shop addition (21'x60' added on to an existing 40'x60') is coming along.
Had to let go of my electrician due to the fact that he never shows up etc.
He installed a new 3-phase service entrance. From said entrance we are
feeding a sub-panel to the old shop. This subpanel is single phase 100 amp.

I am to install a second 50 amp 3 phase sub-panel to another section of the
new shop. My question is wiring for the run to the sub-panel. I purchase
some 3-#6 wire (52' run). This is 3 #6's and a ground wire. 4 wires total.
Out of this 3-phase sub, I will be running circuits for my wife's kilns
(220v), my 3-phase machines and a few 20 amp (120v) plug circuits. I am
confused about the 120 volt circuits. Being that I only have 4 wires (3
current, one ground), how do I run a neutral wire to these circuits. Even
more confusing is that the neutral and the ground all run to the same bus
bar, so what is the difference?

If you have 3 ph delta 220, you will be able to supply 220 1 ph for the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from any
hot to ground won't be 120 volts).

If you have 3 ph wye, you can pull 120 from any hot to neutral, but you
won't have 220 1 ph for the kilns. You'll have 208 instead.

So the first thing you need to know is whether you have a delta or
wye feed.

Gary

"Gary Coffman" wrote in message
...
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V, obviously.

Harold

"Ivan Vegvary" wrote in message
...
My shop addition (21'x60' added on to an existing 40'x60') is coming
along.
Had to let go of my electrician due to the fact that he never shows up
etc.
He installed a new 3-phase service entrance. From said entrance we are
feeding a sub-panel to the old shop. This subpanel is single phase 100
amp.

I am to install a second 50 amp 3 phase sub-panel to another section of
the
new shop. My question is wiring for the run to the sub-panel. I purchase
some 3-#6 wire (52' run). This is 3 #6's and a ground wire. 4 wires
total.
Out of this 3-phase sub, I will be running circuits for my wife's kilns
(220v), my 3-phase machines and a few 20 amp (120v) plug circuits. I am
confused about the 120 volt circuits. Being that I only have 4 wires (3
current, one ground), how do I run a neutral wire to these circuits. Even
more confusing is that the neutral and the ground all run to the same bus
bar, so what is the difference?

I can give up my investment in the 52' of 6-3 cable, but I can't seem to
find any 6-4 wire (4-#6's, plus ground), at least not at any one of the
home clubs. I could simply add a fourth wire (white neutral) to the 3
phase
sub-panel, where it will simply be bonded with the ground. Or, I could
simply create a neutral by bonding to the ground in the sub-panel and not
run a fifth wire. All very confusing.

Any and all advice appreciated. BTW, I do have on older copy of the
National Electric Code, but can't seem to find the answer therein.

Thanks, Ivan Vegvary

Hi Ivan,

It's usually a lot easier to wire with conduit, so you can use any
configuration of wire that you desire. Finding the exact combination of
needed conductors when dealing with three phase can be difficult. That's
a tough lesson I learned when I wired my first 3 phase place.

Harold

In article , Harold & Susan Vordos says...

Phases A and C to neutral yield 120V, phase B to neutral yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V, obviously.

You are now describing wild-leg delta, with one side centertapped
to ground. Not all delta service comes that way, I think.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

"Harold & Susan Vordos" wrote in message
...

"Gary Coffman" wrote in message
...
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral
yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired
three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V,
obviously.

Harold

Harold

What you describe above is exactly what I have! I note in your later post
that you recommend conduit. Very easy to do in my particular case, and will
do so incorporating 5 wires total.
Thank you so much for your insight.

Ivan Vegvary

On 26 Jul 2004 07:11:08 -0700, jim rozen
wrote:

In article , Harold & Susan Vordos says...

Phases A and C to neutral yield 120V, phase B to neutral yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V, obviously.

You are now describing wild-leg delta, with one side centertapped
to ground. Not all delta service comes that way, I think.


Not all but it's by far the most common run into a small shop or
business since it allows everything to be run off the one feed.

I'd venture to say that at least 99% of the three phase
installations around here are wild-leg delta. I know mine is. I know
of only one installation that might be different but I've not worked
on it so I can't be sure. I know it's the only one I've seen with 3
transformers on the pole. Most are like mine which only has two
transformers.

Wayne Cook
Shamrock, TX
http://members.dslextreme.com/users/waynecook

"Ivan Vegvary" wrote in message
...

"Harold & Susan Vordos" wrote in message
...

"Gary Coffman" wrote in message
...
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for
the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from
any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral
yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired
three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V,
obviously.

Harold

Harold

What you describe above is exactly what I have! I note in your later post
that you recommend conduit. Very easy to do in my particular case, and
will
do so incorporating 5 wires total.
Thank you so much for your insight.

Ivan Vegvary


You're very welcome, neighbor. Hopefully Susan and I can stop by to pay
a visit some day in the future when we're in Portland.

Harold

"jim rozen" wrote in message
...
In article , Harold & Susan Vordos says...

Phases A and C to neutral yield 120V, phase B to neutral yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired
three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V,
obviously.

You are now describing wild-leg delta, with one side centertapped
to ground. Not all delta service comes that way, I think.

Jim

Yep, that's it. I've always known to avoid using the center space on the
panel for power unless I was shooting for 240 volts. The panel looks a
little strange to see the occasional space unused, and it tips one off that
there is something unusual about the system. In my current shop, I have
two panels, one of which is strictly used for 3 phase. The other is wired
single phase only. I was put on a demand meter for three phase, so I
figured I'd restrict the panel solely for that use. The single phase panel
has a different meter.

I've had three phase delta wiring in three different locations in my years,
all of which were that way. The first one was an open delta with only two
transformers. At the castle we had three "pigs" on the pole, just as we
do here. I was told by Utah Power & Light, years ago, that the open delta
system works fine so long as you don't have any large motors to power,
which, at that time, I didn't. The largest was my compressor at 5 horse.

Harold

On Mon, 26 Jul 2004 02:09:49 -0700, "Harold & Susan Vordos" wrote:
"Gary Coffman" wrote in message
.. .
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V, obviously.

That's not 220 delta, Harold. That's 240 volt center tapped wild leg delta.
The 240 volt winding between A and C is center tapped, like normal
household 1 ph. The center tap is used as a neutral. The winding between
A and B is a plain 240 winding with no center tap. And the B to C phase is
phantom, ie there is no third phase winding.

This setup is used for small office buildings and light commercial
buildings where the main loads are 1 ph 120 volts or 1 ph 240 volts,
but where there are some 240 volt 3 ph motor loads, usually air
conditioning, pumps, or elevators.

Gary

"Gary Coffman" wrote in message
...
On Mon, 26 Jul 2004 02:09:49 -0700, "Harold & Susan Vordos"
wrote:
"Gary Coffman" wrote in message
.. .
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral
yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired
three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V,
obviously.

That's not 220 delta, Harold. That's 240 volt center tapped wild leg
delta.

Yeah, that's it, and that's apparently what Ivan has. I've never seen the
220 volt delta system you've described, not here in the west. Doesn't mean
it doesn't exist, it's just not real common.

The 240 volt winding between A and C is center tapped, like normal
household 1 ph. The center tap is used as a neutral. The winding between
A and B is a plain 240 winding with no center tap. And the B to C phase is
phantom, ie there is no third phase winding.

This makes no sense, not to me. Three phase delta, wild leg, like I have,
has three coils (three transformers, it's not an open delta system) and
there is voltage from the B phase to neutral, although it's not intended to
be used. In fact it's 208 volts,
which I have measured more than once. It is true here, and it was true when
I lived in Utah, where I learned about that the hard way when the last house
we owned (wired with three phase delta) gave some problems with wild
voltages. Turns out when the power
company installed the transformers, one of the connections had been made up
over a little insulation, which finally allowed the connection to come
loose. We had wild voltages inside, burning out a few lights fluorescent
lights. We came home from vacation to find the contents of our refrigerator
spoiled because the refrigerator hadn't been running due to the broken
connection.

This setup is used for small office buildings and light commercial
buildings where the main loads are 1 ph 120 volts or 1 ph 240 volts,
but where there are some 240 volt 3 ph motor loads, usually air
conditioning, pumps, or elevators.

That's interesting. Must be something used in your area, because here the
only systems I've seen are either three phase delta, 240 volts,
or three phase star (or wye) 208 volts. Recent experiences tell me that
the wye service is being pushed over the delta so that all phases can be
used for 120 volts.

Harold

In article , Gary Coffman says...


208 wye is common, but falling out of favor.

All of our labs are wired that way. 120 from each phase
to neutral, as most of teh loads are 120. Phase to
phase is only 208 but I use some boost transformers
in critical applications.

Jim

==================================================
please reply to:
JRR(zero) at yktvmv (dot) vnet (dot) ibm (dot) com
==================================================

"Gary Coffman" wrote in message
...
On Mon, 26 Jul 2004 22:48:06 -0700, "Harold & Susan Vordos"
wrote:
"Gary Coffman" wrote in message
.. .
On Mon, 26 Jul 2004 02:09:49 -0700, "Harold & Susan Vordos"
wrote:
"Gary Coffman" wrote in message
.. .
snip-------

If you have 3 ph delta 220, you will be able to supply 220 1 ph for
the
kilns by connecting between any two hots, but there won't be any 120
volt to neutral (delta doesn't have a neutral, and the voltage from
any
hot to ground won't be 120 volts).

Not true. Phases A and C to neutral yield 120V, phase B to neutral
yields
208V. Delta panels *do* (or can) have 120 volts. My shop is wired
three
phase delta and has 5 wires, four conductors ( A, B and C phase, plus
neutral) and one ground. One avoids using the B phase for 120V,
obviously.

That's not 220 delta, Harold. That's 240 volt center tapped wild leg
delta.

Yeah, that's it, and that's apparently what Ivan has. I've never seen
the
220 volt delta system you've described, not here in the west. Doesn't
mean
it doesn't exist, it's just not real common.

220 volt 3 ph delta is found in older industrial plants where most of the
equipment *is* 3 ph.

The 240 volt winding between A and C is center tapped, like normal
household 1 ph. The center tap is used as a neutral. The winding
between
A and B is a plain 240 winding with no center tap. And the B to C phase
is
phantom, ie there is no third phase winding.

This makes no sense, not to me. Three phase delta, wild leg, like I
have,
has three coils (three transformers, it's not an open delta system) and
there is voltage from the B phase to neutral, although it's not intended
to
be used. In fact it's 208 volts,

You find it as an open delta a lot. Since there's typically not much 3 ph
load
where wild leg is used, it doesn't create problems. You would measure 208
from the B phase to the neutral. You wouldn't want to actually use that,
though,
because it would unbalance the center tapped transformer.

This setup is used for small office buildings and light commercial
buildings where the main loads are 1 ph 120 volts or 1 ph 240 volts,
but where there are some 240 volt 3 ph motor loads, usually air
conditioning, pumps, or elevators.

That's interesting. Must be something used in your area, because here
the
only systems I've seen are either three phase delta, 240 volts,
or three phase star (or wye) 208 volts. Recent experiences tell me that
the wye service is being pushed over the delta so that all phases can be
used for 120 volts.

208 wye is common, but falling out of favor. Higher voltages are preferred
now almost everywhere because they allow smaller wires to carry more
power (higher voltage, same current, more power). Lots of 480 3 ph wye
and 277 volt 1 ph. That means transformers are required to get 120 or 240,
but spotting dry transformers around the facility where low voltage 1 ph
is required while distributing power to them at a higher voltage saves a
*lot* of copper (lot of money in any building bigger than a bread box).

Gary

Well that is true you can run smaller wire, but as I found out there is a
dirty little secrete in the above plan. It's the transformers!!! I set up
my shop that way and was going to run 480 volt to my house and step it down
there ( smaller wire less cost, lower % voltage drop etc...) sounds GREAT
on paper, well reality is that it's not cheaper at all! at the shop I have
a 225 amp panel for 208 3phase that I use to feed the 5 ton air unit (
single phase) and lots of wall outlets. To run that panel NEC says min 75
kva transformer. Problem?? that transformer burns 600 watts at idle!! just
keeping it warm! The house is even worse, planed to send 150 amps of 480
up to it, to feed a 300 amp panel. so ole NEC says I need a 112.5 kva
transformer. I have a nice 800lb copper wound K13 rated transformer, and
it burns 1200 watts !!!! IF you could run a smaller transformer you
wouldn't have so much loss, but unlike the power co that will feed 5-6,
200amp houses with a single 50kva can, I have to follow the NEC:-(

William
www.wacworkshop.com

On Tue, 27 Jul 2004 16:23:58 GMT, "William" wrote:
"Gary Coffman" wrote in message
.. .
208 wye is common, but falling out of favor. Higher voltages are preferred
now almost everywhere because they allow smaller wires to carry more
power (higher voltage, same current, more power). Lots of 480 3 ph wye
and 277 volt 1 ph. That means transformers are required to get 120 or 240,
but spotting dry transformers around the facility where low voltage 1 ph
is required while distributing power to them at a higher voltage saves a
*lot* of copper (lot of money in any building bigger than a bread box).

Gary

Well that is true you can run smaller wire, but as I found out there is a
dirty little secrete in the above plan. It's the transformers!!! I set up
my shop that way and was going to run 480 volt to my house and step it down
there ( smaller wire less cost, lower % voltage drop etc...) sounds GREAT
on paper, well reality is that it's not cheaper at all! at the shop I have
a 225 amp panel for 208 3phase that I use to feed the 5 ton air unit (
single phase) and lots of wall outlets. To run that panel NEC says min 75
kva transformer. Problem?? that transformer burns 600 watts at idle!! just
keeping it warm! The house is even worse, planed to send 150 amps of 480
up to it, to feed a 300 amp panel. so ole NEC says I need a 112.5 kva
transformer. I have a nice 800lb copper wound K13 rated transformer, and
it burns 1200 watts !!!! IF you could run a smaller transformer you
wouldn't have so much loss, but unlike the power co that will feed 5-6,
200amp houses with a single 50kva can, I have to follow the NEC:-(

Lets put this in perspective. Our plant's power bills average $20,000
a month. At 4 cents a kWh, we don't even notice the transformer
magnetization current losses. But we certainly noticed the $600,000
savings in wiring the plant by using 480/277 instead of 220.

Gary

"Gary Coffman" wrote in message
...
On Tue, 27 Jul 2004 16:23:58 GMT, "William"
wrote:
"Gary Coffman" wrote in message
.. .
208 wye is common, but falling out of favor. Higher voltages are
preferred
now almost everywhere because they allow smaller wires to carry more
power (higher voltage, same current, more power). Lots of 480 3 ph wye
and 277 volt 1 ph. That means transformers are required to get 120 or
240,
but spotting dry transformers around the facility where low voltage 1
ph
is required while distributing power to them at a higher voltage saves
a
*lot* of copper (lot of money in any building bigger than a bread box).

Gary

Well that is true you can run smaller wire, but as I found out there is
a
dirty little secrete in the above plan. It's the transformers!!! I set
up
my shop that way and was going to run 480 volt to my house and step it
down
there ( smaller wire less cost, lower % voltage drop etc...) sounds
GREAT
on paper, well reality is that it's not cheaper at all! at the shop I
have
a 225 amp panel for 208 3phase that I use to feed the 5 ton air unit (
single phase) and lots of wall outlets. To run that panel NEC says min
75
kva transformer. Problem?? that transformer burns 600 watts at idle!!
just
keeping it warm! The house is even worse, planed to send 150 amps of
480
up to it, to feed a 300 amp panel. so ole NEC says I need a 112.5 kva
transformer. I have a nice 800lb copper wound K13 rated transformer,
and
it burns 1200 watts !!!! IF you could run a smaller transformer you
wouldn't have so much loss, but unlike the power co that will feed 5-6,
200amp houses with a single 50kva can, I have to follow the NEC:-(

Lets put this in perspective. Our plant's power bills average $20,000
a month. At 4 cents a kWh, we don't even notice the transformer
magnetization current losses. But we certainly noticed the $600,000
savings in wiring the plant by using 480/277 instead of 220.

Gary

YES lets keep the perspective! This is not rec.huge.factory :-) I don't
know many/any who have 20k per month power bills, and at the rate I get, it
would be 40k per month as I don't get power at 4 cents per kWh :-( Well
maybe I would if I burned that much ) The smaller transformer costs me
about $35 per month to keep it hot and the larger one will be about $75 per
month. So at about $1300 per year just to keep the transformers hot adds up
FAST. For smaller users the wire cost is not that great. The largest motor
I have is 20 hp and the savings just are not there... If I had it to do
over I would have let the power co provide a second feed for the lower
voltage and only single phase, it would save me a lot of cash and let them
heat the transformer on their dime... That way I would have the cheaper wire
where needed, and the best of both worlds

William....

yes i have a transformer that cost 35.00
just to keep it hot..I need to turn it off been
wanting to do it for 10 years i could have
3500.00 in the bank!Or someone elses pocket

Gary Coffman wrote:


That's not 220 delta, Harold. That's 240 volt center tapped wild leg delta.
The 240 volt winding between A and C is center tapped, like normal
household 1 ph. The center tap is used as a neutral. The winding between
A and B is a plain 240 winding with no center tap. And the B to C phase is
phantom, ie there is no third phase winding.

This setup is used for small office buildings and light commercial
buildings where the main loads are 1 ph 120 volts or 1 ph 240 volts,
but where there are some 240 volt 3 ph motor loads, usually air
conditioning, pumps, or elevators.

Gary

Gary,

I've never seen or heard of a 240V ungrounded bank. I'm not saying they
don't have them, just never heard of them after 32 years doing linework.
There is however, 240V 3 wire service. 3 hot legs, no neutral. I happen
to have one. There is a delta bank of 1-25KVA and 2-10KVA transformers
that feeds just my property. 240V 3 wire single phase to the house,
which all comes off the 25KVA transformer. And 240V 3 wire 3-phase to a
10HP agricultural pump.

Don