In article ,
Jethro_uk wrote:
Are there any conditions when the phase needs to be known? If so how
is it detected?

If you connect a 3-phase motor up wrong, it won't work. Does that count ?

They generally just run in reverse.

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*If you try to fail and succeed, which have you done? *

Dave Plowman London SW
To e-mail, change noise into sound.