Which type of motor will drop out of synchronism and trip when overloaded?

A synchronous motor operates at a fixed speed determined by the supply frequency and the number of poles in the motor. When these motors are running under normal conditions, they maintain synchronism with the supply frequency. However, when a synchronous motor becomes overloaded, it can't maintain the necessary speed to stay in synchronism with the alternating current (AC) supply. The motor essentially 'drops out' of synchronism, which leads to a loss of the synchronizing torque.

As a result of this overload condition, protective devices typically trip the motor to prevent damage. In contrast, other types of motors such as induction motors continue to operate under overload conditions until they reach their thermal limits, often slipping at a lower speed instead of losing synchronism altogether. This characteristic makes synchronous motors distinct in their response to overload situations, as it directly leads to a trip and a halt in operation to safeguard against potential damage.