View Full Version : Double neutrals

Ian Gills
11-29-2007, 07:31 AM
I was hoping to install some AFCIs on my panel and found two shared neutrals covering four circuits/breakers.

Any opinions on whether it is worth running new wire on these circuits to have their own neutral? Are there any benefits other than being able to use AFCI breakers?

One shared neutral is for all receptacles and the basement lights (two circuits).

The other shared neutral is for the kitchen receptacle and the disposal (two circuits).

All of the wiring is accessible (unfinished basement).

Oh, and there was one other problem. In trying to disconnect the neutral for my lighting circuit, the lug will not move and I have stripped the screw. Am I allowed just to cut the neutral near the lug, strip it and place it in another lug? Again I hope to attach an AFCI to this circuit, that's why the issue arose.

11-29-2007, 09:47 AM
The AFCI will not function on the 3 wire circuits.

I don't think it is worth the effort to rewire.

You can cut and move the neutral. Be SURE all breakers are off and be SURE to make a good connection. If you lose the neutral at that point, with the power on, you are likely to get 240 volts to some 120 volt outlets.

Ian Gills
11-29-2007, 09:55 AM

Bob NH
11-29-2007, 09:56 AM
The AFCI has a history of false trips and many pros consider it an immature and lousy product pushed by the manufacturers. The 2005 code requires it in 120 Volt bedroom circuits. The 2008 code requires it in all 120 Volt 15 and 20 Amp circuits.

It would be a little like repacing your Toyota with a Yugo.

Do a search on AFCI at www.mikeholt.com (http://www.mikeholt.com)

11-29-2007, 12:47 PM
I do not do residential and have little experience with AFCI's. IMO in principle they are a good idea. I installed all GFCI on all my branch circuits when I wired my house for safety, 4 kids 4 dogs all worth the extra cost. So ask yourself "Whats my family worth?"

Ian Gills
11-29-2007, 02:13 PM
Here's one solution that might work. The basement lights circuit does not draw much power (3 CFL bulbs). Would I be allowed to wire nut this hot to the receptacle hot in the panel, remove two circuit breakers and install one AFCI i.e. pigtail the hots in the panel?

Bob NH
11-29-2007, 02:38 PM
It is permissible to make a junction in the load center. Many new circuit breakers have terminals that are designed and listed for two conductors. There is a small clamping part under the screw head that accepts a wire on each side screw.

Ian Gills
11-29-2007, 02:41 PM
Yes, my ordinary Square D breakers have this, but my Square D AFCI only has room for one hot wire under the clamp (half of the clamp is covered, I assume on purpose). Consequently I will need to pigtail two hots before connecting to the AFCI, if this is an acceptable way of getting round my problem with the shared neutral.

11-29-2007, 03:58 PM
I would say.......yes.

Unorthodox but it will work.

Is it a code violation???? Could be somehow/somewhere.

Bill Arden
11-30-2007, 07:43 AM
The clamp part is not supposed to have two wires. Strangely you have to wire-nut the hots together first.

As for AFCI, I've found RC Snubber circuits keep them from tripping.

Best of all RC Snubber's can just be plugged in and thus do not fall under the UL requirements....

I wonder how long before they start selling them to reduce false trips.

Edit: Another option is to get a 240V AFCI.

11-30-2007, 03:13 PM
The clamp part is not supposed to have two wires. Strangely you have to wire-nut the hots together first.

NOT TRUE depends on the manufacture.

I wonder how long before they start selling them to reduce false trips.

Hopefully never

Another option is to get a 240V AFCI.

An easier solution than rewiring but costly.