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From: rees@pisa.ifs.umich.edu (Jim Rees)
Newsgroups: comp.dcom.telecom
Subject: Re: Trivia Question About Butt Sets
Message-ID: <14551@accuvax.nwu.edu>
Date: 9 Nov 90 23:20:37 GMT
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In article <14486@accuvax.nwu.edu>, davidb@pacer.uucp (David Barts)
writes:

>Why are butt set leads colored red/black/green instead of
>red/green/yellow?

Wire color codes -- one of my favorite questions!  I can't answer this
one, but this has always amused me:

	Electricity <100v	Electricity >100v	Telephones

Ground	Black			Green			Yellow
Neutral	--			White			Red
Hot	Red			Black			Green

I've used electrician's terms here.  Telephones are actually balanced
line, so there isn't that big a distinction between tip and ring, at
least not at the subscriber's end.

Note that someone used to automotive electrical systems will
electrocute himself when he grabs the black wire in his house fuse
box, thinking it's ground.  And an electrician will disable all his
phones when he connects the green telephone lead to ground.

How did all this come about?