How does the PH controller connect to the AC contactor?

This picture is a question I answered earlier. Display the wiring diagram of motor forward and reverse rotation control, adopt double interlocking of button and contactor to assist electric shock, with self-holding control mode, and the control loop voltage is line voltage. There is no problem in principle, and the basic functions can be realized. However, I think the normally closed contact of thermal relay is generally connected between the contactor coil and the power supply "2". The purpose of this is to open the normally closed contact after the thermal relay runs. At this time, except one end of sb1("1") and one end of the normally closed contact ("2") of the thermal relay, the whole control loop is not electrified, especially the contactor coil, which is effective. Because the thermal relay usually acts because the main circuit current is too large for a long time, the bimetal in the relay will be protected to cut off the main circuit after the temperature reaches the action value, thus protecting the motor and contactor.