120 volt subpanel?

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mbrooke

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Subpanel fed with 3 wires (phase, neutral, ground).

Hot lands on one leg, Neutral lands on second leg and ground lands on neutral buss (which is bonded to frame).

All loads are 120 volts and fed from standard Double pole breakers.:huh:

First for me. What is this violating and should the owner to fix it?
 

Dennis Alwon

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I am confused. Why is the white wire on a phase if this is a 120V panel. Feed one phase move the white to the neutral bar and then the bare ground is the egc. The setup as you have it is non compliant.
 
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Dennis Alwon

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Hard to make sense of what you're saying. Got a picture?
I think he has a subpanel with no egc and the egc is used as a neutral. Silly-- fix it as I stated above. You can even jump the main lug or just use every other space. Of course the load may be an issue.
 

stickboy1375

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Location
Litchfield, CT
I get what he's saying, the neutral conductor is one phase of the bus, hence the two pole breakers for every 120v load... so strange to have been done that way.
 

stickboy1375

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Location
Litchfield, CT
I think he has a subpanel with no egc and the egc is used as a neutral. Silly-- fix it as I stated above. You can even jump the main lug or just use every other space. Of course the load may be an issue.

I believe he has an EGC, the neutral is actually half the bus... so a two pole breaker is supplying 120v and a neutral... So messed up. :)
 

mbrooke

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Technician
You need an egc at the sub panel.

The subpanel has an EGC that lands on the factory provided neutral bar that the branch EGC also land on as well.

The panel is wired that Instead of there being a second phase terminated to the second buss a neutral is terminated to the second buss giving 120 volts between the buss bars.
 

stickboy1375

Senior Member
Location
Litchfield, CT
The subpanel has an EGC that lands on the factory provided neutral bar that the branch EGC also land on as well.

The panel is wired that Instead of there being a second phase terminated to the second buss a neutral is terminated to the second buss giving 120 volts between the buss bars.

Ugh.. ignore...
 

stickboy1375

Senior Member
Location
Litchfield, CT
The subpanel has an EGC that lands on the factory provided neutral bar that the branch EGC also land on as well.

The panel is wired that Instead of there being a second phase terminated to the second buss a neutral is terminated to the second buss giving 120 volts between the buss bars.

I personally would add a ground bar,reland the ground wires to this bar, remove the bonding screw in the neutral bar, reland the neutral conductor to the neutral bar, and reland the neutral conductors off the breakers to that bar... and leave the 2 pole breakers in place..
 

mbrooke

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I believe he has an EGC, the neutral is actually half the bus... so a two pole breaker is supplying 120v and a neutral... So messed up. :)

Yes you are 100 percent right half the buss is neutral and 2 pole breakers connect to the busses. Top pole is black hot the second is white neutral.

It is messed up, this is for 120 NEMA 15r outlets and lights:jawdrop:
 

mbrooke

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I spoke to the owner today regarding this and several other issues. The person who wired this was a friend of his who is an electrical engineer
thumbup.gif

I told him that an engineer is not an electrician and he told me that an engineer is above a sparky and knows way more. He said that he doesnt want it fixed unless I can prove to him that it violates code.
mad.gif
I got curious and started digging thru my NEC and I think he may be right:eek:

These are full sized 20 and 40 space panels fed from 15kva 480 volt step down transformers feeding 120 all over the building.:rant: To clear up confusion I drew this: What do the engineers on here think? Kosher to left alone?
 
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texie

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Location
Fort Collins, Colorado
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Electrician, Contractor, Inspector
I spoke to the owner today regarding this and several other issues. The person who wired this was a friend of his who is an electrical engineer
thumbup.gif

I told him that an engineer is not an electrician and he told me that an engineer is above a sparky and knows way more. He said that he doesnt want it fixed unless I can prove to him that it violates code.
mad.gif
I got curious and started digging thru my NEC and I think he may be right:eek:

These are full sized 20 and 40 space panels fed from 15kva 480 volt step down transformers feeding 120 all over the building.:rant: To clear up confusion I drew this: What do the engineers on here think? Kosher to left alone?

At first blush it looks OK as you are using breakers and not fuses. And the secondary is grounded.
 

stickboy1375

Senior Member
Location
Litchfield, CT
I spoke to the owner today regarding this and several other issues. The person who wired this was a friend of his who is an electrical engineer.
I told him that an engineer is not an electrician and he told me that an engineer is above a sparky and knows way more. He said that he doesnt want it fixed unless I can prove to him that it violates code.

And trains are on tracks so "engineers" can drive them. lol....
 

mbrooke

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Location
United States
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Technician
I don't see a GEC drawn in. Don't each of these transformers require one?

Do you have electrical inspections in your area? Were they done? Pulling that card may not gain you any points though.

Golly gee. Where is the main breaker? Are the transformers protected? Feeders?

The building most likely was inspected when first built but has had a buffet of renovations, additions and modifications.

The transformers are protected by fused disconnects and by breakers in the 480v panels which also feed HVAC, motors. Typical single phase 25kva unit is protected by 60amp 600v rated fuses and has #6 cooper and a #8 ground in 1 1/2" conduit.
 
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