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
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...)
replace "fly" with "com" to reply.
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.
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.
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"
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: ...and only 1 ground - something I still can't
There only needs to be one ground because the grounds of each
receptacle in the duplex are mechanically (and therefore electrically)
the same point. Even if you split the duplex into 2 separate
receptacles as a I mentioned in an earlier post, the grounds will still
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 :-)
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