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Joined: Oct 2004
Posts: 7
F
foggy Offline OP
Junior Member
I know when wiring a 3-way light, a 3-conductor loomex will run between the 2 3-way switches' box, and normally the black one will be chosen as common, and the white and the red ones as travellers. The question is, can I use the white as common, the other two as travellers? I checked the code, but could not find the answer.

Joined: May 2001
Posts: 144
T
Moderator
4-034 * Three Way Switch Wiring

In some instances, it has been brought to our attention that the grounded circuit conductor is being switched in some three way lighting arrangements that are currently being installed. This is contrary to OESC 4-034, and 14-016 and in the interest of consistency will not be accepted.

Tony Moscioni
Electrical Inspector
Electrical Safety Authority

Joined: Oct 2004
Posts: 7
F
foggy Offline OP
Junior Member
Thank you, Tony. CEC4-034(2) says it's not necessary to render the identified conductor if the connections are made so that an unidentified conductor is the return conductor from the switch to the outlet. I made a simple drawing in which I think the circuit is not against the rule. http://www.geocities.com/halosome/fauto/3way.JPG

Joined: Sep 2003
Posts: 650
W
Member
Tony,

I don't think you misunderstood foggy's question.

Foggy is asking about the color coding of the wires, specifically using a white wire re-identified for use as an ungrounded switched conductor in a three way switching circuit.

The quote that you posted speaks to illegal three way switch circuits where the grounded conductor was switched. The simplest example would be one where you have two switches at two locations, each with a supply grounded and ungrounded conductor and a switched conductor feeding the lamp. Both supply leads are connected to the _traveller_ terminals, and then a conductor run from the _common_ terminal to the light fixture. With two switches you have two conductors, and depending upon switch position either conductor could be grounded or ungrounded. If both conductors are grounded, the lamp is off. If one is grounded and the other ungrounded, then the lamp is on. If both are ungrounded, then the lamp is off again, but electrically live.

-Jon

Joined: Dec 2003
Posts: 36
D
Member
4-034 subrule 2 return conductor to outlet or light can not be identified (white)


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