Double lugged neutrals

[Larry Schmid]

I know this has been discussed in detail here before, but my computer is acting up and will not let me look in old files. What is the code for a violation on double lugged neutrals? Also, what is the code on a neutral and ground under the same lug? Thanks for the quick help.

[Jeffrey R. Pope]

The same code applies to both conditions. . .

408.21 Grounded Conductor Terminations. Each grounded conductor shall terminate within the panelboard in an individual terminal that is not also used for another conductor.

[Bruce A. King]

Are you going to report the code # ?
I just state that it should be done according to the panel manuf. specs. (which are usually covered up with wiring on the inside of the panel.)

Correct terminolgy is double tap, use "double lug" for service and feeder doubles.

Two and sometimes three equipment grounds are allowed per screw but only one neutral. No mixing of gnds and neutrals either under one screw.

I think the latest NEC has it under 408.21 according to code check.

[Michael W. Gault]

See it everyday...
write it up everyday...
get poked in the eye only occasionally now

[mlopezi]

Very common around here with houses built in the 60's.

[David A. Andersen]

Same here!
They think neutral - grounds all go to the same place anyway!

[Paul W. Abernathy]

Intent: This new section should ensure that grounded (neutral) conductors terminate within the panelboard to an individual terminal. This has been a UL requirement (UL Std. 67 – Panelboard Standard) for some time, and the addition to the NEC is intended to bring this information to the installers. Technically, this is covered by 110.3(B), which requires all equipment to be installed in accordance with the manufacturer's installation instructions and markings, but nobody knew it existed. UL Std. 67 (Panelboard Standard) permits up to three 10 AWG equipment grounding conductors to terminate on a single terminal, if the terminal is marked for this purpose. Figure 408-3

The intent of this requirement is to ensure that the grounded (neutral) conductor of a multiwire branch circuit is not momentarily disconnected, which could result in the destruction of electrical equipment and fires from overvoltage.

[Greg Fretwell]

I think this is far from the most serious thing you see unless it is indicating a panel that is stuffed beyond it's capacity. If you are looking at an otherwise clean panel with no evidence of a lot of hack work I would not be alarmed to see double tapped neutrals

[Larry Schmid]

Thanks for all the quick help. Bruce, you are correct, I would never quote a code #, but is good to have for my own reference when talking to builders. Greg, does than mean you would not write it up in your report if you saw it? Thanks again for all the information.

[Greg Fretwell]

I might mention a double lugged neutral but it would not be listed as a hazard unless it was just an indication of other unlicensed activity. Until 2002 this was not really a code issue, it was only how you read the label in the panel. Lots of sparkies were taught to group the neutral and ground for each circuit and I don't know of any real problems caused by that. When you see a panel stuffed beyond it's capacity, with doubled lugs, I would address the overloaded panel as the hazard.

[Paul W. Abernathy]

Greg,

The Standard 67 has been around in the UL for years, as for the code it states equipment must be installed as instructed by the manufacturer and most panels were to comply with Standard 67 which did not allow double lugging of the grounded conductor on the terminal .

The real problem is the WHAT IF concerns for the consumer and the idea of a shared neutral on a multi-wire setup.....all which could cause issues if the " SITUATION" is right.....lol

The intent of adding it to the 2002 NEC -

Intent: This new section should ensure that grounded (neutral) conductors terminate within the panelboard to an individual terminal. This has been a UL requirement (UL Std. 67 – Panelboard Standard) for some time, and the addition to the NEC is intended to bring this information to the installers. Technically, this is covered by 110.3(B), which requires all equipment to be installed in accordance with the manufacturer's installation instructions and markings, but nobody knew it existed. UL Std. 67

[Paul W. Abernathy]

I should mention however......I don't loose any sleep over this VIOLATION...lol.......just as a FYI......

My brother STILL twists his Grounded and EGC's of the same branch circuit and puts them under (1) screw......and the only AHJ to FAIL him was....well.......ME when I was filling in for an Mun. Inspector.....Family...what are you gonna do...lol

[Speedy Petey]

This is SOP in my area for a lot of electricians. Like Paul said, nobody fails it.
I myself used to do it this way for years.

[Paul W. Abernathy]

Speedy...I only failed it because it was my brother..thehehe...I later removed it and was fine with it. Now with that said I have not done it in years as it was like 1994 before I knew about it......and then changed from doing it.

But I think the reason we did not see it failed alot was that even many of the Mun. Inspectors did not know about it......so when the 2002 bought it to light....it probably will increase as you know how some AHJ's can be with a little power.......not all of them...I know some SUPER nice ones...but then again I have worked with some that are NOT ....lol

[Joe Funderburk, CMI]

I agree this is not the worst violation that could exist. However, NC requires me to distinguish "significant" issues from others (the significant ones go in the Summary by regulation).

One of my criteria I use to determine what is significant is "any electrical issue is considered significant". Since I'm not an electrician, I don't feel comfortable in itemizing which issues are significant and which are not. I just call them all out as significant and let the Sparkys sort it out.