How do you wire a three phase forward - reverse starter?
You start with a normal one way circuit consisting of a three
phase contactor and an three phase overload in series for the
forward circuit. Then you add the reverse contactor in parallel
with the forward contactor but with line one and line two crossed
over i.e. when the reverse contactor is made, line one of the
supply will be connected to line two of the motor and line two of
the supply to line one of the motor. The control circuit must also
be interlocked to prevent forward and reverse being energized at
the same time.