3 phase motor controls

[JdoubleU]

I came a cross a 3 phase condensate pump that was controlled by a Float. The control wire did not go to a starter to energize a coil and close a 3 phase contactor. They just used one phase and ran it through the float switch. It works fine but how. Shouldn't this single phase the motor and is it legal.

 

[ptonsparky]

Some float switches are 2 pole hp rated, I suppose you could get a 3 pole hp rated switch. The two pole would stop/start it and the 3P of course would or could meet all the NEC requirements for control.

 

[augie47]

I'd look closely. I know of no way you could just switch one phase. As Tom says, it probably switches two of the phases. Not uncommon in HVAC controls also.