POWER CIRCUIT FOR STARTER MOTOR

PROBLEM TO BE SOLVED: To prevent deterioration of an electric device and a circuit due to a short-circuit without unnecessarily disconnecting a breaker. SOLUTION: This power circuit for starter motor comprises: a power supply 2 for the starter motor 4 for internal combustion engine; a main switch 1a; and a first relay switch 3 operating in conjunction with the main switch 1a and controlling current supply to the starter motor 4 for internal combustion engine. This power circuit for starter motor comprises: a breaker 6 arranged between the power supply 2 and the starter motor 4 for internal combustion engine; a second relay switch 7 carrying out bypass of a current with respect to the breaker 6; and a controller 8 carrying out control such that when the main switch 1a are reversed to be turned ON, the first relay switch 3 is turned ON, when the main switch 1a is reversed to be turned OFF, the first relay switch 3 is turned OFF, and when the first relay switch 3 is ON, the second relay switch 7 is turned ON.