receptacle
I am replacing some receptacles in my Master Bedroom. I have replaced 7 so far and they all have the same setup: 4 wires and 1 ground. They are straight forward to replace.
When I opened the last receptacle, I found out that it had 9 wires: 8 wires and 1 ground (see attached picture)I couldn't understand how this work and how I could replace it and closed it back. That receptacle is not connected to any switch.
Why do I have 9 wires for that receptacle? How can I replace it?
There should be no problem doing what you want.
One set of conductors brings power from an upstream device or outlet, while the other takes power to a downstream device or outlet. The two black conductors are electrically bonded through the receptacle, as are the two white conductors. You'll notice that the bonding tab on the side of the receptacle is still in place, which means that the two receptacles are connected together.
If you're simply replacing the existing receptacle, with an identical (or similar) receptacle of a different color. Simply connect the new receptacle exactly as the original is connected.
NOTE: When terminating conductors at a screw terminal, always wrap the conductor in a clockwise direction. This will cause the conductor to be pulled in tight, when the screw is tightened down.
I'm not sure what conductor combinations the supplied twist-on wire connectors are rated for, so I'm going to assume they're only rated for 2 #14 conductors (check the documentation). So before you start, you'll want to pick up a couple Ideal yellow twist-on wire connectors.
If your hypothesis is correct, which it most likely is, that the switch controls one of the outlets, then the extra pair of wires in that outlet have to do with the switch. Either they provide a separate loop to control just one half of the outlet (some switched outlets are like that: a switch just controls one of the receptacles out of the pair). Or else the extra wires are meant to be in series with the outlet, going out to the switch.
It sounds as if you miswired it so that the switch hookup is in parallel with a receptacle's hot and neutral (thinking that it's a daisy chain connection to the next outlet).
When you do that, guess what happens. Everything works when the switch is open, and when you close it, it short circuits.
A half-switched outlet, if that's what your friend has, normally requires three connections (not including ground). Two wires will come from the breaker, and two from the switch giving you four. This means two of them get connected together. How this happens is that the switch receives hot, and so it screwed to the same terminal as hot, or otherwise spliced to hot. The return wire from the switch feeds the secondary hot that controls the switched part of the receptacle.
The best way to proceed here is to turn the power off at the breaker and verify continuities: in particular, which pair of wires corresponds to the switch. With the power on, you should also check that you haven't wired any outlet with the opposite polarity: neutral being hot and vice versa.
Best Answer
Assuming that they aren't a split circuit, just bundle them all by color and add a pigtail to each bundle for the outlet. You'll need red wire nuts to handle that many wires, assuming #14. Some brands will accept five #12. Make sure you do a clean job of combining and twisting the bundle to ensure good contact.