Three-phase motor automatic time-limited commutation circuit

As shown in the figure, KT1 and KT2 are time relays. After closing the main switch QS, K1 pulls in, KMF pulls in, the motor rotates forward, and KT1 starts timing. When KT1 reaches the timing, it automatically disconnects, the K1 coil loses power, KMF is released, and the motor stops; at the same time, the normally open contact of KT1 closes, the coil K2 pulls in, the KMR coil receives power, the motor reverses, and KT2 starts timing. . When the KT2 timer arrives, its normally closed contact KT2 is disconnected, the K2 coil loses power, KMR is released, and the motor stops. The loss of power of K2 causes its normally closed contact to return to the normally closed state, KT1 and K1 work, and the motor enters forward rotation. Afterwards, the process is the same as mentioned above, starting over and over again, so that the three-phase motor enters the automatic limited time cycle working state.