Three Recepticle Box/Outlet/Switch Questions

Reply

  #1  
Old 03-30-06, 04:24 AM
stuemke
Visiting Guest
Posts: n/a
Three Recepticle Box/Outlet/Switch Questions

Question #1)
In a box, the wires seem to come in pairs. At the top and bottom of the box, through the holes that are provided, wires seem to come through with one black and one white in a pair. Does it stand to reason that these two wires run to the same source (ie. both go to the next parallel switch or outlet)?

Question #2) One of the outlets in our living room has six wires going into it with no pigtails. It has the hot wire screwed to the side screw (with the negative on the other side), and the two parallel lines going through the push pins on the back (one black and white pair on top, one black and white pair on bottom). Is this legal, or should they be pigtailed using wire nuts?

Question #3) In a single-pole switch, does the neutral coming into the box basically bypass the switch (continuing on to the fixture), and the hot coming into the switch is the only one used? I'm thinking that this setup would allow the switch to simply be an interrupter, and that turning the switch on and off just lets the electricity flow through the black wire while the white wire is always present.

Does all this make sense?

Thanks for the help.

-stuemke
 
Sponsored Links
  #2  
Old 03-30-06, 04:37 AM
Member
Join Date: Sep 2003
Location: Central New York State
Posts: 13,973
1. Electricity needs two wires. The two wires are a hot and a neutral (also called a return). When running from box to box, the wires must be together such that the current flowing in one direction matches the current in the other direction. In most residential settings in the US, NM type cable is used.

2. There is no negative in an AC system. There are hot wires, there are grounded wires, and there are ground wires. The hot and the neutral (grounded) wires carry current. The ground wire is for safety and under normal situations does not carry current.

It is against code to put more than a single wire under a screw terminal, but there is nothing in the code against using the screw terminals and the back stabs, as long as you only have one wire under each screw.

Most of us here recommend against using back stabs, so in your situation most of us would recommend a wire nut with a pigtail to the receptacle screw.

3. You are correct, when discussing 120 volt systems where the white wire is a neutral. All that is necessary is to break the hot wire.
 
  #3  
Old 03-30-06, 09:21 AM
Join Date: Mar 2006
Location: Fort Collins, Colorado
Posts: 159
Originally Posted by stuemke
Question #1)
In a box, the wires seem to come in pairs. At the top and bottom of the box, through the holes that are provided, wires seem to come through with one black and one white in a pair.
There's an aspect of your question that troubles me. Whatever the wiring method, there should be something sticking into the box to protect the conductors until they enter the box.
  • For Romex, the sheathing of the romex should enter the box for at least a quarter of an inch, before being opened up to expose the conductors.
  • For "BX", there should be a connector attaching the metallic sheathing of the cable to the metallic box.
  • For conduits, there should be a connector connecting the conduit to the box.

Do you see white and black conductors leaving the box without any sign of them being a part of a cable?

Question #2): I agree with Racraft.

Question #3): Exactly right. The neutral should (almost) never be switched. If you were to use the neutrals to turn the light (or whatever) on and off, then when the light were turned off, people would assume it was not energized. But it would be energized, and the person working on it would be shocked.

If you see a white wire entering a switch, it is not a neutral - it is a white conductor that is live that hasn't been re-identified as a hot conductor.

(Or, some yahoo is switching neutrals illegally. But that's less likely.)
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'