hooking 10-2 wire to 20 amp receptace safe

Every name brand receptacle I have seen is listed for 14-10 ga wire.

Hi, Why not?

At least a Pass & Seymour recep will accept 10AWG.

I suppose asking why someone would wire a whole house with 10AWG is silly?

Did the installer also use 1900 boxes with plaster rings? I'd be concerned about box fill.

nate

There's "it'll physically work" and "code compliant."

If the receptacle is not listed for the wire sizes used, it's not code compliant, even if the screws will back out far enough to allow the wire to be inserted. Inspectors don't care about "works and looks safe" their job is to enforce code...

(very, very familiar with this effect from a previous job... any "outside the box" solution has to be evaluated for code compliance)

nate

There is absolutely nothing in the NEC code that prohibits upsizing the wire gauge, indeed that is the norm for extra long runs to limit voltage drop.

I would use heavy duty commercial grade outlets that have the side clamps. Basically, you strip the wire, insert it under the clamp, then tighten down the screw to secure the wire. I would verify the wire capacity specifications of the outlet, but I would trust the clamping style more than trying to wrap a 10 gauge wire around a screw.

Anthony Watson

Nothing on the wire size itself, certainly; could run 4/0 if wanted... :)

But there is the compliance of the connections do have to match. Agree that any normal receptacle will accommodate #10, but there is that correspondence that is in Code.

It's no real problem -- I've done a lot in the shop and other farm outbuildings. Just takes a little better pair of pliers and a little more effort in making the bend, but if one is used to fencing and the like... :)

I got that, I was more referring to the devices' terminals not being specifically listed for the wire gauge used.

Also, the breaker should be appropriately sized for the devices used; I don't believe the exception that allows a 20A breaker to be used on a circuit feeding multiple 15A receptacles applies to higher currents (e.g. you couldn't use a 30A breaker on a 10AWG circuit if you are installing 20A receps.)

nate

Oh, and the box fill needs to be evaluated for code compliance as well. Any kind of single gang box is probably not code compliant here... by current code two 14/2s and a device require a 3.5" deep single gang box, which is the deepest that you can practically use in a studded wall.

nate

Hi, I always thought so.

A 3x3x3.5 (18cu/in) would accommodate 2 #10/2 and a device (17.5 computed fill). That is the same box you need for 2 #12s and a device with a little more wiggle room (15.75 fill). You can get 2 #14/2 and a device (14 fill) in the 2 3/4" box (14 cu/in).