Three motors start sequentially and stop circuit in reverse sequence

Some technological processes need to start three motors M1, M2, and M3 in sequence, and stop them in reverse order of M3, M2, and M1. In this circuit, since the normally open contact of KM1 is connected in series to the KM2 control loop and the normally open contact of KM2 is connected in series to the KM3 control loop, if KM1 does not close first, that is, the motor M1 does not start first, the motor M2 cannot start; Motor M2 does not start, and motor M3 cannot start either. This is "sequential start". "Reverse sequence stop" is because the normally open auxiliary contact of KM3 is connected in parallel to both ends of the STP2 stop button, and the normally open auxiliary contact of KM2 is connected in parallel to both ends of the STP1 stop button. In this way, the motor M2 cannot be stopped without stopping the motor M3, and the motor M1 cannot be stopped without stopping the motor M2.