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- Newsgroups: sci.electronics
- Path: sparky!uunet!zaphod.mps.ohio-state.edu!pacific.mps.ohio-state.edu!linac!att!att!allegra!rfc
- From: rfc@allegra.att.com (Robert F. Casey)
- Subject: Re: Various national colour code of wires (e.g. earth) for elec. plug
- Message-ID: <1992Dec15.191356.22205@allegra.att.com>
- Organization: AT&T Bell Laboratories, Murray Hill, NJ
- References: <6912@otc.otca.oz> <519@bit.UUCP> <1992Dec14.133335.21707@cs.hw.ac.uk>
- Date: Tue, 15 Dec 1992 19:13:56 GMT
- Lines: 29
-
- Someone mentioned, in this thread, that, in USA, white is only used for the
- neutral power return. But there is one exception that I've seen: Imagine
- you have a ceiling light controlled by a wall switch. And that the powerline
- source comes into the ceiling box, and you have a two wire (excluding the
- safety ground) cable running to the switch. The two wires connected to
- the switch. Two wire cable ("BX", "Romex") only comes with a white wire
- and a black wire, in addition to the ground. So, how to wire the switch,
- what color for what? Usually, what gets done is to make the white wire
- to the switch the hot supply, and the black the switched hot. So, the
- light fixture will be supplied with a black (switched hot) and white (neutral)
- from the source. and the hot white going to the switch connected to the
- hot black source.
-
- box in ceiling box on wall
- hot black============--------------------- hot white
- source switch
- neutral white------- =================== switched black
- | |
- light bulb
- in ceiling
-
- safety grounds connect all boxes too.
-
- Go to the library and they should have a book on housewiring. It's just
- as easy to do it correctly as to do it wrong. And if you do it right,
- and you neglect to have your work inspected, it's doubtful that they will
- ever know you did anything.
-
- Disclaimer: Don't blame me.
-