Electrical Panel

[Gary Winfield]

Couple questions ?? I made an inspection and noticed double tapping on the electrical panels. Somewhere I thought I heard that you could double up with neutrals to neutrals or ground to ground. But NOT a neutral with a ground.

Not sure True or False ??

See photos

[Gunnar Alquist]

Couple questions ?? I made an inspection and noticed double tapping on the electrical panels. Somewhere I thought I heard that you could double up with neutrals to neutrals or ground to ground. But NOT a neutral with a ground. Not sure True or False ?? See photos

Grounds are ok to double (or triple in some cases), if allowed by the panel's manufacturer. Current carrying conductors (hot & neutral) are not.

The problem was with the wording in the past NEC. The wording essentially stated that terminals for more than one conductor should be labeled by the panel's manufacturer. If you look at the label, you will find that they allow multiple grounding conductors under a single terminal screw, but not multiple grounded. As a result, many electricians and building inspectors believed that multiple neutrals were ok when they were not.

I believe that in the 2002 NEC, the wording was changed so that it was clear that multiple neutrals could not be secured under a single terminal screw. I do not have the specific code sections in front of me.

[keithsines]

I don't have my 2011 code book in front of me but I believe the section you are looking for is 408.41. If you have the handbook it explains why only one neutral per lug is used. When troubleshooting a circuit with two neutrals under the same lug the circuit you are not working on could still be energized. Keith

[Speedy Petey]

When troubleshooting a circuit with two neutrals under the same lug the circuit you are not working on could still be energized. KeithExactly. It is not as much of a safety issue under normal conditions as many would make it out to be. It becomes an issue during troubleshooting in that removing one conductor could create a live backfeed on the other if it became loose or free of the neutral buss.

[Bill Kriegh]

Even more of an issue with doubled neutrals is the problems that arise if a multi wire circuit is involved.

Another common misconception seems to be that if the hot wires are landed on a breaker that allows 2 wires to be terminated on it that the neutrals can be under the same screw. The NEC says otherwise.

[Scott Patterson]

Couple questions ?? I made an inspection and noticed double tapping on the electrical panels. Somewhere I thought I heard that you could double up with neutrals to neutrals or ground to ground. But NOT a neutral with a ground.

Not sure True or False ??

See photos

Is that a service panel or a downstream panel?

[Jim Port]

Is that a service panel or a downstream panel?

Really wouldn't matter. The rule of one neutral per hole would still apply.

However, the neutrals would need to be isolated from the grounds in a non-service panel.

[Scott Patterson]

Really wouldn't matter. The rule of one neutral per hole would still apply.

However, the neutrals would need to be isolated from the grounds in a non-service panel.

Thus the reason for my question. :)

[Jim Port]

I mis-understood the intent of your question Scott.

[Gary Winfield]

Scott;

These were (2) 200 amp panels, 240 volts side by side in the garage utility room. They were practically the same. I'm assuming they were service panels. All the entrance lines were underground.

http://www.inspectionnews.net/home_inspection/attachment.php?attachmentid=21040&stc=1&d=1296693569

[Benjamin Thompson]

My guess would be that those are both downstream / branch / sub panels and the neutrals and grounds shouldn't be bonded but the picture is pretty blurry.

[Speedy Petey]

My guess would be that those are both downstream / branch / sub panels and the neutrals and grounds shouldn't be bonded but the picture is pretty blurry.
What do you base this on?

[Benjamin Thompson]

What do you base this on?
Well, where I am a disconnect is required (by the power company) to be accessible outside of the home, usually that's done with a main breaker or 2. I don't know the rules in Tennessee

[Michael Thomas]

Somewhere I thought I heard that you could double up with neutrals to neutrals or ground to ground. But NOT a neutral with a ground

WRT multiple neutrals under a single terminal, see: http://paragoninspects.com/articles/pdfs/electrical/panels/internal/multiple_neutrals.pdf

[Gary Winfield]

Good link Michael !!!

Thanks

[Speedy Petey]

Well, where I am a disconnect is required (by the power company) to be accessible outside of the home, usually that's done with a main breaker or 2. I don't know the rules in TennesseeI see you are in the SW. Yes, this is common to your area, but not many others. In most of the country an outside disconnect is not required nor is it typical.

[Benjamin Thompson]

I see you are in the SW. Yes, this is common to your area, but not many others. In most of the country an outside disconnect is not required nor is it typical.
I kind of figured that when you questioned me. Good to remember!