GFCI breaker and other things

[jodil]

My question has two parts:

I met with the electrician that had wired a friend of mines house today to go over some issues I had with the panel. Some were justified, others (in the electricians eyes) were not.

In this first pic as you can see theres a bunch of double tapped neutrals. You cant see it in this pic, but there are a couple of scorched neutrals at the bottom where the plastic coating has melted off.

This has been a continuous topic of frustration for me. Yes I know it is not right. But EVERY electrician I have spoke to (or gotten chewed out from) says thats the way they do it...

So now what?

Then pic two... This GFCI breaker has two hot and two neutrals. You can see the plastic in the breaker is cracked. The electrician says this is the way it is supposed to be wired... (just an fyi this one breaker controls garage, baths, and exterior.) What do you think?

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[Richard Moore]

On the first, the doubled neutrals, language was added to the NEC in 2002 (originally 408.21 and then became 408.41 in the 2005 & 2008 NEC) to clear this up.

408.41 Grounded Conductor Terminations. Each

grounded conductor shall terminate within the panelboard

in an individual terminal that is not also used for another

conductor.

Exception: Grounded conductors of circuits with parallel

conductors shall be permitted to terminate in a single terminal

if the terminal is identified for connection of more

than one conductor.

Before that, it relied more on the listing of the panel neutral bar. However, I don't think anyone has ever seen wording in a panel that would suggest the terminals can be used for more than a single grounded (neutral) conductor. As far as we HI's are concerned, it's pretty safe to say that all neutrals should terminate one per hole, by itself, and anything else is wrong.

"But EVERY electrician I have spoke to (or gotten chewed out from) says thats the way they do it...

So now what?"

Well...you are sure you are right and they are wrong. Tell your client that and suggest they, not you, have the electrician provide proof otherwise. There's only so much you can do when faced with this.

The second photo is also wrong. Those particular terminals are designed for a single conductor and double-tapping is not allowed, period.

[hausdok]

Hi Rich is right on all counts.

The electrician was trying to lie his way out of an embarrassing situation. He should have installed a second GFCI breaker for that second pairing of wires.

OT - OF!!!

M.

[jodil]

A couple questions.

What is a parallel conductor?

How do you know if a particular breaker is rated for two wires? I have asked a similar question before, but I need to know the exact verbage of what it says on the inside of the breaker..

Thank you!

[Richard Moore]

Parallel conductors are sometimes used for larger feeds to increase capacity. I don't know the exact math but you might be able to use a pair of 1/0 Als instead of a single 4/0 Al conductor to provide 200-amps. It's not something you are too likely to come across in a residence. And...the terminals still need to be listed for more than one conductor.

There are two types of breakes that are designed for 2 conductors. Most recent Square-D (homeline and QO) and Cutler Hammer CH breakers from 10 to 30 amps can be doubled. BUT...it is only most and not all.

The terminals are clearly different and the breakers will have info marked on the sides. See these photos of a Square-D breaker...

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In the second photo you can see how the plate would balance pressure on the conductors trapped in the grooves on either side. Sorry, but I don't have a CH photo.

[Richard Moore]

BTW Jodi, just so you can explain to your clients why double-tapped neutrals are not allowed...

There are two reasons; both valid. The first is that any changes to the panel might involve loosening the terminal screw and leave a hot circuit with an unintended open neutral...which can be hazardous. The second, and the one I find most compelling, is that the screw in a normal round lug might only be applying pressure on one of the conductors, leaving the other loose. As neutrals carry current under load, that can lead to constant arcing and might be the cause of your scorched or melted neutrals (I say might because there could be other reasons). This "quality of connection" issue is the same for breakers, and why they shouldn't be double-tapped unless designed and listed for it.

2 or 3 grounding conductors are usually allowed in the very same lugs because any current on those would be the result of a ground fault and should be only momentary before the breaker trips.

[Eric B]

Jodi,

I tell clients that my job is to tell them what the industry standards are and that I don't expect that every single thing that I point out will be corrected. It's like making a complete stop at a stop sign - it's a law that most of us fudge on.

If the electrician wants to fudge on the double taps that's fine with me. But I don't have the authority to say that they're ok. I suspect that if the electrician had to write a report that he had to put his signature to, like you and I do, he'd be more cautious about what he'd ignore.

A few years ago an "electrician" said that having a few amps on the home's water lines was acceptable. I asked if he'd be willing to put that on company letterhead and sign it. He said he would. As far as I was concerned I was done with that situation. I had "qualified" people write statements that separated trusses, holes on heat exchangers etc were acceptable conditions. If the client wants to go along with such stuff it's their decision. I've learned to not waste energy over letting it frost me (at least most of the time).

[Erby]

Since I started using this, I get very few questions when calling out doubled neutrals:

========

The problem(s) discovered in the panel such as

more than one "grounded conductor" (neutral /white) wire per screw on the neutral bus bar (double tapped/lugged) Each "grounded conductor" is supposed to have it's very own screw on the bus bar, no other "grounded conductor" or "equipment grounding conductor" (bare copper wire) should be under the screw with the "grounded conductor".

{Some electricians (who haven't done their homework) will tell you that it is OK to have more than one neutral (white) wire under a screw on the bus bar. They are wrong. It has long (at least as far back as 1967) been required by manufacturer's instructions and Underwriters Laboratories Standard 67 for panelboards. See this link for a narrative description of the reason for single neutral wire - single screw. Double Lugged Neutral Narrative Also see this link for a visual interpretation. Double Lugged Neutrals Visual}. Ensure the electrician is familiar with UL Standard 67 requirements and

any other problems that an electrician may discover while performing repairs need correcting. I recommend a licensed electrician repair as needed.

[jodil]

Thats great Erby! Thank you! Im going to start using that verbage right away.

Heres another question, what if you have only one buss bar in the panel and all the neutrals and grounds are jambed into it? I see this alot....Then what?

Thanks

Jodi

[Erby]

Don't just use it. Change it around to make it Jodi talking as you see fit.

Re your question, it's my understanding that

1. If it's the panel with the service disconnect and the neutrals each have their own screw, it's OK

2. If it's a sub panel (i.e. the main disconnect is elsewhere) it's wrong.

Jim Katen is better at elaborating on that.

He's probably who I stole the verbiage above from.

[Richard Moore]

Jodi, If your question is what to do if there aren't any spare holes, then it's normally a very simple matter for an electrician to install an additional (cheap) grounding bar. See http://brands.hardwarestore.com/47-your-one-source.aspx for some examples.

[Brandon Chew]

Originally posted by jodil

Heres another question, what if you have only one buss bar in the panel and all the neutrals and grounds are jambed into it? I see this alot....Then what?

Thanks

Jodi

Fireworks! [:-party]

Underlining was mine. I assume you meant to write terminal bar.

Neutrals and grounds are required to be electrically connected at the service equipment (main disconnect). They are required to be kept separate from each other everywhere else.

Every neutral needs to be by itself under a terminal screw. If allowed by the label on the panel, more than one ground can be under one screw. If there are not enough terminals, as Richard pointed out, in most cases an electrician can add more.

[jodil]

Ok I understand that eachneutral wire must be along under its own screw on the terminal bar at the main. But is it ok for a grounding wire to be under that same screw with the neutral? (I would guess no) Or if the ground is just in the next hole under its own screw?

But subpanel grounds and neutrals separated...

gottcha

[hausdok]

Nope

OT - OF!!!

M.

[Jim Katen]

Originally posted by jodil

Ok I understand that eachneutral wire must be along under its own screw on the terminal bar at the main. But is it ok for a grounding wire to be under that same screw with the neutral? (I would guess no)

You guess correctly.

- Jim Katen, Oregon