TestRed
Test RED phase - is it high? (this is my ref. point)
- - If NOT goto TestRed
Wait for 6.6mS (50Hz mains, three phase)
Test YELLOW phase - is it high?
- - If so then all is on track -- GOTO YelGood
Test BLUE phase - is it high?
- - If so then we are running backwards -- GOTO BluBad
Signal that a phase is missing - GOTO TestRed
YelGood
Wait for 6.6mS
Test BLUE phase - is it high?
- - If so then one phase complete -- GOTO SeqGood
Signal that a phase is missing - GOTO TestRed
SeqGood
Signal that all is well
GOTO TestRed
BluBad
Wait for 6.6mS
Test YELLOW phase - is it high?
- - If so then one phase complete -- GOTO SeqRev
Signal that a phase is missing - GOTO TestRed
SeqRev
Signal that phases are reversed
GOTO TestRed