Neutral and grounding conductor terminations

[mgbinspect]

The crazy part about this subject is that I'd have to call this condition out four out of five times., In fact, I've started calling it out, but wondering why it's been permitted by the local building departments right up until pretty much this year. It's frustrating.

[charlieb]

The crazy part about this subject is that I'd have to call this condition out four out of five times., In fact, I've started calling it out, but wondering why it's been permitted by the local building departments right up until pretty much this year. It's frustrating.

The munis overlook this detail every day here. Some electricians (via the builders) are beginning to get the program

[Jim Katen]

I'm getting push back from a builder regarding the neutrals and grounds being under the same lug. I just want to be sure I'm providing the correct source for this opinion that the neutrals need to be under there own seperate lugs. Is NEC, section 408.21 the correct reference?

Thanks

It was the correct reference in 2002 when that rule was introduced. Now it's been moved to 408.41.

Even before 2002, though, the rule was still implied in that you couldn't put more than one wire under a terminal unless the terminal was identified, or approved, for more than one. That rule goes back to about 1937.

- Jim Katen, Oregon

[Charlie R]

See it here in Maryland all the time, never had any electrician agree that it was a problem. That, and double-taps for the dang doorbell. If there are other issues I write for the client to hire an electrician to fix the other issues AND the neutral wiring. If it's just the neutral wiring, and everything else looks OK, then I write that the client should be aware this common issue exists, period. I have noticed that the past couple of years in new construction inspections, it's been done right so I don't know if someone here is starting to crack down on it or not.

[Mark P]

yea I wright it up all the time. Around here many of the AHJ don't even remove the panel cover.

[Graikos]

I have a question. I inspected a new house for the home owner that had the grounds and neutrals double tapped. As I was pointing this out he mentioned to me that he has had issues with certain breakers that would trip. He said that one of them would trip at 9:15 PM every night. He had the builder send over his electrician who didn’t find anything wrong. He also had two other electricians come. One of them told him that it was the AFCI and that they are sensitive but tends to act normal after a few months. The electrician changed the breaker and after a while the homeowner said it has not happened for a couple of months. This is a Siemens panel. As I noted earlier, the grounds and neutrals are tapped together within the same lug hole. Would this cause the problem he is having? I did do some research but I am unable to find an actual wiring schematic or any info about this particular situation. The AFCI's neutral were in their own lug hole. I am just wondering if the other ground and neutral double taps could affect this.

[Marc]

I have a question. I inspected a new house for the home owner that had the grounds and neutrals double tapped. As I was pointing this out he mentioned to me that he has had issues with certain breakers that would trip. He said that one of them would trip at 9:15 PM every night. He had the builder send over his electrician who didn’t find anything wrong. He also had two other electricians come. One of them told him that it was the AFCI and that they are sensitive but tends to act normal after a few months. The electrician changed the breaker and after a while the homeowner said it has not happened for a couple of months. This is a Siemens panel. As I noted earlier, the grounds and neutrals are tapped together within the same lug hole. Would this cause the problem he is having? I did do some research but I am unable to find an actual wiring schematic or any info about this particular situation. The AFCI's neutral were in their own lug hole. I am just wondering if the other ground and neutral double taps could affect this.

I don't know if that would cause nuisance tripping of an AFCI but I do know that old light fixtures with failing connections or switches may cause them to trip.

As an example, grab a incandescant table lamp and twist the bulb back & forth so as to make it flicker quickly. If it's on an AFCI protected circuit, I've known it to trip the AFCI.

Marc

[Denray]

An electrician told me once that a double lugged neutral that he was responcible for caused him to have to replace a bunch of computer equipment in someones house. He never doubles them anymore.

[Bain]

An electrician told me once that a double lugged neutral that he was resoncible for caused him to have to replace a bunch of computer equipment in someones house. He never doubles them anymore.

I don't understand. How could a double-tapped neutral damage computer equipment?

[Denray]

Perhaps it became loose and the arcing caused a problem?

[kaltes]

We find doubled lugged neutrals on breaker panel buss bars in more than 50% of my inspections here in Austin. I call it out whenever I see it.

[wfrench123]

Gentlemen,

Are you wondering why they made this rule?

It is because neutrals are live wires with separate power sources. If you turn off a breaker and a certain circuit is dead, you should be able to disconnect its neutral from the neutral bar, (and the circuit's live and ground wires from the entire panel for that matter) with out dealing with another live wire (neutral in this case) shoved in the same hole.

The code shies away from using the word neutral because the neutral isn't actually neutral, it's live, hot, and can kill you. It only becomes a grounded conductor when it is firmly attached to the neutral bar, when it is loose, it's a live wire.

On a similar note, I personally believe that neutral wire number labels in panels should be required by the NEC.