Outlet wiring

[Eigenvector]

On most outlets that I've seen there are 2 wire clamps per side. Each clamp has 2 holes - so conceivably there can be 4 wires going to side of the outlet (and only 1 ground - something I still can't fathom). But anyway, calling them top and bottom wire clamp - is there any reason why you must install 1 wire per wire clamp on an outlet if you have outlets chained together in a circuit? This assumes you aren't going to have multiple breakers per outlet or have different switches control different outlets.

You especially see this on GFI outlets, where they cover the bottom clamp and make it otherwise appear that you shouldn't even USE the bottom clamp

[Nate Nagel]

You really only should have one wire per screw terminal, unless you are using the "spec grade" type of outlets where they have the little clamps and you don't need to bend the wires around the screw

You shouldn't use the "load" side of a GFCI unless you specifically want to protect the outlets downstream of the GFCI. The sticker is there to keep people from hooking the "line" to the "load" terminals and ending up without protection. But you *do* always try the "test" feature after installing a GFCI don't you? (there's a REASON it's there...)

nate

[RBM]

On a standard duplex outlet, you can use all four screws or clamps, although if you have to many wires, it would probably be more secure to make a pigtail with just one wire to hot and neutral on the outlet. On GFCI outlets, the "load" terminals are taped just so you know that unless you want to protect downstream outlets, you only use the open or "line" terminals

[DerbyDad03]

I'm not sure if this relates to your question, but if you look at a standard receptacle, you will see a "bridge" connecting the 2 screws on each side. If you break off this bridge, you can separate the duplex into 2 receptacles, perhaps to have one switched and one always hot.

Eigenvector wrote:

[DerbyDad03]

Eigenvector wrote: ...and only 1 ground - something I still can't fathom...

There > On most outlets that I've seen there are 2 wire clamps per side. Each clamp

[Eigenvector]

Yes I always test my GFI outlets after installation, but really my question is more about convention than anything.

You alluded to it above, mentioning "spec grade" outlets, which is what I have where you can easily put 2 wires under a single clamp without degrading the contact or stability of the circuit. So basically in this case is it more for creating clean outlets where the wires are easy to distinguish by having them under individual clamps?

Also with GFI outlets, what if you chain GFI outlets together? Would you still connect them using the load terminal or not? I've heard it said that you generally shouldn't chain GFI outlets together using the load terminal because one GFI tripping would trip all the others - but obviously I'm not certain of that.

[RBM]

If you daisy chain GFCI outlets together and don't want downstream outlets protected by the upstream unit, you pigtail or connect to the "line" terminals only

[John Gilmer]

It's not a good idea to diasy chain GFCI as it makes it a little more difficult to figure out what "tripped."

OTOH diasy chaining the GFCIs doesn't create any kind of safety hazard (or than the hazard created when a needed circuit can't be reset.)

The house we now have had a good amount of DIY wiring. The usual problems:

3-way and 4-way switch circuits didn't function correctly, grounding was sloppy in places, and there were GFCIs in "series" in places. Once I figured things out the series connection didn't do any harm.

Were a "downstream" GFCI to fail I would likely replace it with a regular outlet but I'm not going to change it out otherwise.

[John Gilmer]

Any junction box with a GFCI is crowded. If it has 3 cables coming in, it's even more crowded. Add two wire nuts and the pigtails ...

[dicko]

It sounds like you have the outlets where there are 2 screws on each side and each screw has 2 holes to clamp 2 wires, so you have holes on each side.

There's no reason why you cant use both holes per screw to clamp down wires, however, if you are screwing down the wires, instead of clamping, only 1 wire per screw is allowed.

Some people frown on using the outlet as a junction for multiple wires. The reason being that if you ever have to replace or otherwise remove the outlet, everything downstream of that outlet goes dead. If you had pigtailed only 1 wire to each screw, the entire circuit would remain live while it was replaced. That of course assumes that you can replace an outlet with the power still on :-)

dickm

[Mark Lloyd]

I know someone who connected 8 wires to a receptacle - 4 to the screws and 4 to the backstab holes.

[Eigenvector]

Alright, thanks for the information.