Sub panels and grounding

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1

Originally Posted By: smcintire
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2

Originally Posted By: jpope
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If it is, in fact, a sub panel (equipment panel) in the same building as the service panel, it’s wrong, plain and simple.


Neutrals must be isolated from the panel box and the grounds bonded to the box. It should be fed by four wires from the service panel (H+H+N+G) or, three wires (H+H+N) in a metal conduit as the EGC.

--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738

3

Originally Posted By: smcintire
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http://www.nachi.org/bbsystem/usrimages/more/P1010005.JPG ]

4

Originally Posted By: jpope
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Your reference would be IRC 3507.2 and NEC 250.24(A)(5) which prohibit regrounding of the neutral after the service, with exceptions for separate buildings.

–
Jeff Pope


JPI Home Inspection Service


“At JPI, we’ll help you look better”


(661) 212-0738

5

Originally Posted By: jpope
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I’ll be waiting for one of our resident Sparkies to come in and blow holes in my reference and interpretation icon_wink.gif , but as HI’s, that is how we should call it.

–
Jeff Pope


JPI Home Inspection Service


“At JPI, we’ll help you look better”


(661) 212-0738

6

Originally Posted By: smcintire
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Jeff, thanks I just never find these correct. It’s kind of like the saying how can so many people be wrong and I am right, just makes me wonder sometimes if I am missing something. thank you.

7

Originally Posted By: Greg Fretwell
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jpope wrote:
I'll be waiting for one of our resident Sparkies to come in and blow holes in my reference and interpretation ![icon_wink.gif](upload://ssT9V5t45yjlgXqiFRXL04eXtqw.gif) , but as HI's, that is how we should call it.


It works for me
8

Originally Posted By: Ryan Jackson
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Works for me too. Well done Jeff

–
Ryan Jackson, Salt Lake City

9

Originally Posted By: bbadger
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Jeff, Do you want to be a electrician in Mass.?


Of course you will have to adjust to the white stuff that falls part of the year. ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)

--
Bob Badger
Electrical Construction & Maintenance
Moderator at ECN

10

Originally Posted By: jpope
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bbadger wrote:
Jeff, Do you want to be a electrician in Mass.?

Of course you will have to adjust to the white stuff that falls part of the year. ![icon_smile.gif](upload://b6iczyK1ETUUqRUc4PAkX83GF2O.gif)


I don't do well in temps below 60 degrees But thanks for the invite

--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
11

Originally Posted By: Russell Frame
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jpope wrote:
If it is, in fact, a sub panel (equipment panel) in the same building as the service panel, it's wrong, plain and simple.

Neutrals must be isolated from the panel box and the grounds bonded to the box. It should be fed by four wires from the service panel (H+H+N+G) or, three wires (H+H+N) in a metal conduit as the EGC.


An academic question. What if there are only a few 120v circuits in the sub? Do you still have to feed it with multiple hots?
12

Originally Posted By: jpope
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Russell Frame wrote:
An academic question. What if there are only a few 120v circuits in the sub? Do you still have to feed it with multiple hots?


I would think not. So long as the breakers are on the same side ![icon_rolleyes.gif](upload://iqxt7ABYC2TEBomNkCmZARIrQr6.gif) But that would just be silly, now wouldn't it?

--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
13

Originally Posted By: ddavis
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This seems to be old install with a sub panel. This needs to be updated.

14

Originally Posted By: Ryan Jackson
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Jeff: Typically breakers on the same side would be on alternating legs or phases. Think about a typical 2 pole breaker.

–
Ryan Jackson, Salt Lake City

15

Originally Posted By: jpope
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Ryan Jackson wrote:
Jeff: Typically breakers on the same side would be on alternating legs or phases. Think about a typical 2 pole breaker.


![icon_redface.gif](upload://f7DX2EWhmUfsDapWaYT3oJHMCj1.gif) I knew that. Friggen trick question

--
Jeff Pope
JPI Home Inspection Service
"At JPI, we'll help you look better"
(661) 212-0738
16

Originally Posted By: Ryan Jackson
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icon_lol.gif Yeah, I know you knew that. Thats why I had to jump on it before you caught it and edited it. icon_lol.gif

–
Ryan Jackson, Salt Lake City

17

Originally Posted By: Russell Frame
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icon_lol.gif

18

Originally Posted By: Brian A. Goodman
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Steve,


They can easily convert that panel to two bars (1 neutral, 1 equipment ground) by removing the metal jumper bar between them. As Jeff noted, the bonding of the enclosure must be on the equipment ground bar, not the neutral bar.


Seperating the wires won't be too tough either. Getting the 4th wire in for the equipment grounds will be the hard part.

19

Originally Posted By: jpeck
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Brian A. Goodman wrote:
Steve,
They can easily convert that panel to two bars (1 neutral, 1 equipment ground) by removing the metal jumper bar between them.


Brian,

I will re-phrase that for you.

They can easily convert that panel to two bars (1 neutral, 1 equipment ground) by REPLACING the metal jumper bar between them with the plastic bar made for that purpose.

--
Jerry Peck
South Florida
20

Originally Posted By: Brian A. Goodman
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Jerry,


I’ve never seen a plastic bar made for that purpose. The only reason it’s there to start with is to provide a conductive path between the two bars, it serves no other purpose that I know of. Take it out and you’re done.