Circuit is to provide cyclical soak testing of solenoids. Relay simulates solenoids with the contact of the relay simulating a reed switch. The logic input connected to the relay contact is to simulate a bad solenoid (0=bad). The XOR gate outputs a high signal as long as either a) solenoid is not energized, or b) solenoid is energized and reed relay closed. Capacitor and resistor at S/R S input smooth out the small time period that output is zero due to timing issue. Pushbutton connected to S/R R resets the flip-flop and hence the fault LED.
