The third protection circuit to prevent short circuit when the motor is started in reverse

This circuit adds a contactor KM3, and connects its main contact in series to the main circuit . It will operate regardless of
the forward or reverse contactor action. In this way, during the forward and reverse conversion process, four power outages are required ( Main circuit
and control loop (two places each), which can effectively extinguish the arc and prevent the occurrence of phase short circuit .