1. As illustrated in Fig. 8, the SM bar is located on the upper part of the electromagnet.
2. If the diaphragm is broken, the rod adopts an abnormal sideways motion and the protruding part of the rod (S) comes in contact with the switch bar. The SM is broken, contact is interrupted and the power is cut.

Take the bar handle between fingers (Fig. 8) and insert firmly down into the retaining slot of the switch terminal. If the bar is correctly inserted, it cannot be pulled free. Double check that the bar is correctly inserted.