3 phase moor/2 phase supply

[Leecatt]

Today I saw something interesting which I do not quite understand.
I was called to finish off a job started by another electrician.

The white phase was not present during his visit so he had removed the white cable on top of the main circuit breaker and bridged that load onto the red phase, on top of the main circuit breaker.
This was a few weeks ago.

The 3 phase motors for the swimming pool and the 3 phase aircon units all carried on running on the two phases.
In other word two of the sets of winding would have been red and one would have been blue.
Strange.

(The aircon units did not heat up the rooms as required using 2 phases, but we found that it still doesn't work even with all 3 phases reinstalled.
Thats a problem for the aircon guy though)

[AndyD]

It's possible that a 3-phase motor would still run under this wiring arrangement but at a greatly reduced torque and at higher temperatures than normal. I'd check the motor protection on both the air-con and the pool pump because they should have tripped due to high line current.