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John Kogel
03-02-2009, 09:10 PM
Howdy y'all, my first post here.:)
I found this split nuetral connection in a panel recently. A subpanel was added using the 125 A breaker at the top of the pic. Looks like the electrician didn't have a big lug connector to connect the neutral properly, 40 miles from town. I'm fairly sure it is incorrect code-wise, even up here in the Great White North.
My question is, Is it unsafe? Would you automatically call it out?

John Kogel
Home Inspection in Victoria BC, Sidney, Sooke, Saanich, Duncan, Cobble Hill, Mill Bay, Chemainus, Crofton, home inspector (http://www.allsafehome.ca)

Jerry Peck
03-02-2009, 09:28 PM
My question is, Is it unsafe? Would you automatically call it out?

John,

First, welcome to THE inspectors board.

Second, to answer your questions: Yes and Yes.

Another thing I see missing of even greater importance (is it is indeed missing) is no equipment grounding conductor run to the remote electrical panel. The raceway those conductors go into looks to be PVC, and if not PVC you would need a grounding bonding lock nut/bushing on it through those concentric knock outs bonded over to the grounding terminal bar.

Raymond Wand
03-03-2009, 04:41 AM
The sub panel can I believe have a ground installed at the subpanel by means of a grounding rod.

Fred Warner
03-03-2009, 05:29 AM
Raymond, you have just opened a can of worms.
If the sub panel is within the same building or structure, the method will be having a 4-wire feeder assembly routed from the service panel to the sub/remote panel. No ground rod necessary.
If the sub/remote panel is in another building or structure then 250.32 comes into play. :)

Raymond Wand
03-03-2009, 06:06 AM
Good morning Fred,

I agree with your second sentence. However if the feed is from the mains to an out building it is okay to have a seperate grounding rod at least from the Canadian Electrical Safety Code.

10-208 Grounding Connections for two or more buildings supplied from a single service.
(a) The grounded circuit conductor at each of the buildings or structures shall be connected to a grounding electrode and bonded to the non current carrying metal parts of the electrical equipment.

Cheers,

Jerry Peck
03-03-2009, 06:31 AM
I agree with your second sentence. However if the feed is from the mains to an out building it is okay to have a seperate grounding rod at least from the Canadian Electrical Safety Code.

10-208 Grounding Connections for two or more buildings supplied from a single service.
(a) The grounded circuit conductor at each of the buildings or structures shall be connected to a grounding electrode and bonded to the non current carrying metal parts of the electrical equipment.


Raymond,

So, where John is, it is okay?

Down here, South of the Border ;) , it gets much more complicated than that, see 250.32(B)(1), (2), and (3) below.

As Fred said, if that is to an out building (a separate structure) then NEC 250.32 applies:

From the 2008 NEC (i.e., there *shall be a grounding conductor run with the feeders*, unless it is an *existing building as allowed under previous editions of the NEC). (underlining is mine)
- 250.32 Buildings or Structures Supplied by a Feeder(s) or Branch Circuit(s).
- - (A) Grounding Electrode. Building(s) or structure(s) supplied by feeder(s) or branch circuit(s) shall have a grounding electrode or grounding electrode system installed in accordance with Part III of Article 250. The grounding electrode conductor(s) shall be connected in accordance with 250.32(B) or (C). Where there is no existing grounding electrode, the grounding electrode(s) required in 250.50 shall be installed.
- - - Exception: A grounding electrode shall not be required where only a single branch circuit, including a multiwire branch circuit, supplies the building or structure and the branch circuit includes an equipment grounding conductor for grounding the normally non–current-carrying metal parts of equipment.
- - (B) Grounded Systems. For a grounded system at the separate building or structure, an equipment grounding conductor as described in 250.118 shall be run with the supply conductors and be connected to the building or structure disconnecting means and to the grounding electrode(s). The equipment grounding conductor shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded. The equipment grounding conductor shall be sized in accordance with 250.122. Any installed grounded conductor shall not be connected to the equipment grounding conductor or to the grounding electrode(s).
- - - Exception: For existing premises wiring systems only, the grounded conductor run with the supply to the building or structure shall be permitted to be connected to the building or structure disconnecting means and to the grounding electrode(s) and shall be used for grounding or bonding of equipment, structures, or frames required to be grounded or bonded where all the requirements of (1), (2), and (3) are met:
- - - - (1) An equipment grounding conductor is not run with the supply to the building or structure.
- - - - (2) There are no continuous metallic paths bonded to the grounding system in each building or structure involved.
- - - - (3) Ground-fault protection of equipment has not been installed on the supply side of the feeder(s).
- - - - Where the grounded conductor is used for grounding in accordance with the provision of this exception, the size of the grounded conductor shall not be smaller than the larger of either of the following:
- - - - - (1) That required by 220.61
- - - - - (2) That required by 250.122
- - (C) Ungrounded Systems. The grounding electrode(s) shall be connected to the building or structure disconnecting means.
- - (D) Disconnecting Means Located in Separate Building or Structure on the Same Premises. Where one or more disconnecting means supply one or more additional buildings or structures under single management, and where these disconnecting means are located remote from those buildings or structures in accordance with the provisions of 225.32, Exception No. 1 and No. 2, 700.12(B)(6), 701.11(B)(5), or 702.11, all of the following conditions shall be met:
- - - (1) The connection of the grounded conductor to the grounding electrode, to normally non–current-carrying metal parts of equipment, or to the equipment grounding conductor at a separate building or structure shall not be made.
- - - (2) An equipment grounding conductor for grounding and bonding any normally non–current-carrying metal parts of equipment, interior metal piping systems, and building or structural metal frames is run with the circuit conductors to a separate building or structure and connected to existing grounding electrode(s) required in Part III of this article, or, where there are no existing electrodes, the grounding electrode(s) required in Part III of this article shall be installed where a separate building or structure is supplied by more than one branch circuit.
- - - (3) The connection between the equipment grounding conductor and the grounding electrode at a separate building or structure shall be made in a junction box, panelboard, or similar enclosure located immediately inside or outside the separate building or structure.
- - (E) Grounding Electrode Conductor. The size of the grounding electrode conductor to the grounding electrode(s) shall not be smaller than given in 250.66, based on the largest ungrounded supply conductor. The installation shall comply with Part III of this article.

Raymond Wand
03-03-2009, 06:40 AM
Jerry,

Thanks for the info. I don't know if Johns installation is correct because he didn't mention the distance from the house to the outbuilding. But it is common at least in my area to see both grounding methods. If the subpanel (garage) is close to the main feed, then I would run a ground from the main panel. But if the outbuilding is further away a ground rod is permissable.

John may wish to check with his local electrical inspector for a definitive answer.

Cheers,

Fred Warner
03-03-2009, 07:18 AM
Hey Jerry, thanks for the voluminous material. It was too much for me to type and I do not have the code on CD. :)

Roland Miller
03-03-2009, 08:14 AM
It is definitely not code compliant. Just as the blue neutral is not code compliant. If you are not under the 2008 NEC then a separate structure subfed panel may not need the equipment grounding conductor routed with the others. To say it is unsafe is a loaded question. The NEC is considered the minimum installation for electrical safety.

I had a hotel service I inherited as a red-tag. It was in immenient danger of burning down at any time. The service had been that way for 45 years before it was red tagged. So be careful calling something electrically unsafe as there are only a few articles in the NEC that specifically deal with electrical safety and a good portion of the articles are installation standards for specific product groups.. Using the terminology "not National Electrical Code compliant" will keep you from defending something that has no immediate hazard..

Raymond Wand
03-03-2009, 09:36 AM
I would like to correct myself. The sub-panel must be grounded back to the source as indicated in the photo, and as Jerry, Fred, Roland alluded to.

John Kogel
03-03-2009, 08:45 PM
The sub panel is in a garage maybe 75 feet from the house, with its own ground rod. Triplex to the shed and a ground rod at the sub is permitted in British Columbia, AFAIK. :D

I did call for a check of panel and branch circuits by a certified electricianbut for other reasons. You may notice solid Al nuetrals in the picture, plus there were other issues.

What about the bonding of the sub-panel neutral under 2 screws?

Jerry Peck
03-03-2009, 08:57 PM
What about the bonding of the sub-panel neutral under 2 screws?

John,

That's what I thought you were asking about, and what I responded to.


I found this split nuetral connection in a panel recently.

My question is, Is it unsafe? Would you automatically call it out?


Second, to answer your questions: Yes and Yes.

By the way, unless you were in one of those things at the top of my Avatar, and found one of those things at the bottom of my Avatar, ... that is not a "subpanel", it is simply a "panel" or a "distribution panel", or possibly a "remote panel" as it is located "remotely" from another panel. :)

John Kogel
03-03-2009, 09:27 PM
Well Jerry we always call that remote panel a subpanel. :)

And yes, I see that you say yes it is unsafe, and yes you will call it so.
Does everyone agree?
In other words, if I call for an electrician to make the 80 mile round trip to improve that neutral connection, he won't call me an idiot?

Jerry Peck
03-03-2009, 09:43 PM
In other words, if I call for an electrician to make the 80 mile round trip to improve that neutral connection, he won't call me an idiot?


That's not the ONLY electrical thing on your report is it?

Then don't worry about that, he is to address ALL things on the report while on site, especially if he has to make an 80 mile round trip - to do otherwise would make him an idiot. :)