How do I wire a 3 wire 220v timer

[Mague]

I want to install an itermatic electronic time switch on the line that feeds my 220v window AC. It is connected to a 3 wire 220v outlet. There is a Red, Black and White wire. The Black and Red are connected to the circuit breaker. The White wire is connected to the Neutral bus.

The timer has a Line 1, Line 2 and ground connection.

I suspect I connect the Red and Black to Line 1 and Line 2 ... What do I do with the White wire? I also suspect that I just wire nut the power and load white wire together.

 

[nehog]

Is the timer 240 volts or 120 volts? In fact, what's the model of that timer, I can look it up...

 

[404]

Until further info, cap the white wire off.

 

[Mague]

The timer is an Intermatic GM40AVE-R. It's rated at 120 - 277 vca.

 

[gregtwojeeps]

Correct, the red and black conductors from the breaker go on L1 and L2 terminals on the timer as being the "power in" conductors. Wires from the AC outlet should go on T1 and T2 terminals which may also be marked "load".. Read the instructions/wiring diagram to be sure the timer clock will accept 120 - 277 VAC if so, your good to go and will not need a neutral for a 120 VAC rated clock motor...

As above, the white wire could be spliced through as mentioned, as the 220 VAC window unit does not need a neutral conductor... BUT..... if the cable supplying the power to the AC unit does not have a bare or green conductor in it being used as the EGC (equipment grounding conductor) , the previous electrical installer may have used the white conductor as the equipment grounding conductor. (not kosher or code compliant, but it happened in the old days) so it would need to be marked with green tape to designate its function. Work safe. JMO

 

[Mague]

Got it. Thanks so much for your help.