There are two clear giveaways that identify a switch as being a three way type. Since the 3 ways have the load on the common terminal the travelers can both test hot.
How To Wire A 3 Way Light Switch Family Handyman
3 way switch no traveler. The master switch requires a line 110vac with neutral and ground and load. The chicago 3way or tunnel lighting was was allowed by special permission from the inspection dept. A 3 way lighting circuit consists of 2 light switches controlling a single load ie. If it was wired with knob and tube originally its possible that the 3 way switch was old enough to be wired as carter 3 way. The hot wire leading from the 3 way switch circuit will have no power since all power must travel through the switches. With conduit the wire colors for travelers could be any color.
The wt00z is great for use in dual switch 3 way applications creating a virtual 3 way switch without need for a traveler wire fitting into any standard single gang electrical junction box. Traditionally the slave requires a line and traveler wire to the master. There are three screw terminals on the body of the switch in addition to the green grounding. At the hot end the incoming hot wire is connected to the common terminal. The colors will vary depending on whether nm cable or conduit was used. Thats why i suggested looking at the faq thread.
Three way switches have three terminals with the one that is not for the two travelers being called the common. In any 3 way there is a master and slave switch. If one of the black hot wires does have power then that is the wire for the always on plug. The switching was designed for a a watchman that had to punch a time clock that he carried with him. Four way switches have four terminals to connect two traveler pairs to the incoming pair and the outgoing pair. A three way wall switch is a common type of light switch that makes it possible to control a ceiling light or other electrical fixture from two different locations in a room.
With nm cable the wire colors for travelers will be black and red using 3 wire cable. There is no standard for wire colors on 3 way switch travelers. In a hallway or large room for example installing three way switches at both ends lets you turn the light fixture on or off from both locations. There are no onoff markings on the switch toggle. Here in us wire color isnt consistent. Such markings are not needed with this type of switch as they are.
In this setup the load is switched between h n on h h off n h on and n n off. In a situation where a 14 3 romex is the only wire in a switch box the white is either a traveler or load. At joshslade needs to determine which 3 way setup he has so we can help him reconfigure the wiring if possible to make this work. In the 2nd diagram below blue wires are used for travelers. Image from popular mechanics october 1971.
Gallery of 3 Way Switch No Traveler
