The hot is the ungrounded conductor, the one with voltage to ground, usually black or red on 120/240 V residential work and brown, orange or yellow on 277/480 V systems. As an adjective it means energised: a hot panel, working it hot, a hot tap. Calling a wire hot says nothing about where its voltage comes from, which is why switch legs, travelers and shared neutrals catch people out.
Black is the hot, white's the neutral, and that red is a switched leg to the fan, check all three before you cut.
Also heard as
- hot leg
- line
- live
- ungrounded conductor
Related terms
Wild leg
The one phase of a four-wire delta service that reads about 208 volts to neutral instead of 120.
Switch leg
Conductor that carries switched power from a switch to the light or load it controls.
Get bit
To take an electric shock on the job, as in got bit by a hot neutral.
Traveler
One of the two conductors run between three-way switches, carrying power on whichever path is selected.