davidb@pacer.uucp (David Barts) (11/09/90)
Obscure Telecom Trivia Question No. 608: Why are butt set leads colored red/black/green instead of red/green/yellow? David Barts Pacer Corporation, Bothell, WA davidb@pacer.uucp ...!uunet!pilchuck!pacer!davidb
rees@pisa.ifs.umich.edu (Jim Rees) (11/10/90)
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?
pozar@uunet.uu.net (Tim Pozar) (11/12/90)
In article <14551@accuvax.nwu.edu> rees@citi.umich.edu (Jim Rees) writes: >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. Other than battery polarity? Some sets will not power the DTMF encoder unless they are wired in the proper polarity. Tim uunet!hoptoad!kumr!pozar Fido: 1:125/555 PaBell: (415) 788-3904 USNail: KKSF-FM / 77 Maiden Lane / San Francisco CA 94108
jmc%eniac@relay.eu.net (Miguel Casteleiro) (11/13/90)
In article <14551@accuvax.nwu.edu>, rees@pisa.ifs.umich.edu (Jim Rees) writes: > 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 Well, here it's different: Electricity >100v Ground Black or Blue Neutral Yellow and Green (in stripes) Hot Brown The rest are the same colors! Miguel Casteleiro at INESC, Lisboa, Portugal. UUCP: ...!mcsun!inesc!jmc