On boats, stern drive motors usually have a tilt feature to raise the propeller in shallow water. An electric motor is used to raise and lower the drive unit. If anything prevents the drive unit from moving up or down, or if the operator continues to press the switch after the unit is fully up or down, there will be a surge of electric current going through the motor – which will burn up the motor’s windings. Our circuit breaker detects that surge and cuts power to the system, thus protecting the electric motor.