15amp breaker on 20amp circuit - ok?

[Mike]

I am installing devices on some new circuits in my house.

The circuits all have 12/2 wire and 20amp breakers.

If I install 15amp outlets, can I use these devices to bridge feed-in and feed-out wires in boxes?

That is, consider a box that has two 12/2 wires, one feeding in and one feeding out to another box. I could use the outlet to tie together these two wires. Or, I could pigtail the whites and blacks and then go from the pigtail to the device. The former approach where the outlet connects the wires is easier, but I am not sure if 15amp outlets are rated for 20amp pass-through.

(I know that a one-outlet 20amp circuit must have a 20amp outlet)

Thanks,

mh

[gfretwell]

All NEMA duplex 5-15r devices are U/L rated for 20a feed through. You are right about the "one outet" deal.

[Randy Cox]

Yeah it is easier.............but not that much easier. Look at that tiny little "bridge" that runs between the two white screws and the two brass screws on the duplex device. That "bridge" is designed to break off so that one of the two can be switched and the other non-switched. That bridge is the smallest spot on the circuit loop you will be building if you put the device in the "easier" way.

It is a bottleneck of resistance. It is so small that it won't cause that much heat or power loss..........but it will cause heat and it will cause power loss. Why would you want to build in that constant drain of power?

There is another problem. Whether you wrap the wire around the terminal screw or use whatever alternate means of connection at the device...........that terminal point is subject to failure more so than a live spring connection at a pig-tail in the box behind the device. When one of those many terminal points (multiple use of the easier "bridge" method) fails..........it will affect the entire circuit downline from it. So you can do it, but a lot of people think the better way is to pigtail at each box.

When I was young and in a hurry, I did it your way. Now that I'm old..........and I ought to be in a hurry..........I do it the pig tail way.

Randy R. Cox

[No]

But pigtail is still best practice IMO. Why not do it?

[Kevin Ricks]

The best approach is to pigtail and I believe is required by some local codes. I have found that in the long run, pigtailing is less effort and neater especially with 12 ga wire. Also if one outlet goes bad, it does not disturb the rest of the circuit. If you are not going to pigtail then use the more expensive outlets with 'back feed'. These are the outlets where you push the wires (up to 4 sets) into the holes and then tighten the screws on the side (like what a GFCI outlet has). Do not use the 'back stabs' on cheaper outlets. Code does not allow you to use 'back stabs' with 12ga wire anymore.

Kevin

[Toller]

Oh come on! It is so short that the voltage drop would not be measurable. And if it is not measurable, how much of a constant drain could it be?

I have never even heard of a screw terminal failing. They certainly don't fail more often than wire nutted connections. You are wirenutting three wires instead of screw terminating one wire; I would be willing to give odds that the one wire is more secure.

As one person said, pigtailed connections don't stop the whole circuit if an outlet goes bad; that alone is a legitimate reason to pigtail, though not a big enough one to make me want to pigtail.

And yes OP, it is just fine to use a 15a breaker and 15a devices with #12 wire. In fact it is actually necessary on long runs to avoid excessive voltage drop, and perfectly reasonable on shorter runs as well.

[Mark Lloyd]

I recently changed some receptacles (4 in series) from back stabbed feed-through connections to screw connections and pigtails. I found one receptacle that works with back stabbed connections but not screws. I replaced that one, and corrected a grounding problem (multiple receptacle grounds connected together, but no earth ground).

[Mike]

Thanks for all of the advice.

All of my outlets are the "more expensive" ones that have backfeed. So, when I am using the outlets to bridge between feed-in and feed-out, the bridging is done with these outlets.

Mike