With input voltage applied, normal temperature condition (thermal switch closed) and no seal leakage, the over temperature relay is energized and the seal leak relay is de-energized. Both LEDs, are green, indicating normal conditions and input voltage is applied. When the motor temperature rises and the N.C. thermal switch opens, the over temperature relay is de-energized, open a contact that had been closed and turning off the pump contactor. The TEMP LED turns red. If the over temperature condition is cleared, the unit will reset automatically. If the seal starts to leak, contaminating fluid enters the pump motor cavity. This lowers the resistance between the internal probe and the common connection. When the resistance deops below the user-adjustable sensitivity set-point of the relay, the output relay energizes and closes a contact, which can be used to give an alarm indication of a leaking seal. The LEAK LED turns red.