| 摘要 |
<p>A DC distribution board comprises, therein as internal devices, a circuit breaker 5 provided along each of branch lines branched from main wires of a direct-current power supply, and a controller 6 for controlling switching of the breaker 5. The circuit breaker 5 comprises: power connecting terminals t1, t2 connected to the main wires; load connecting terminals t3, t4 connected with wires from a load; a semiconductor switch device 57 provided along an electrical circuit between the terminals t1, t2 and the terminals t3, t4; a current sensing resistor 56 for detecting an electric current through the electrical circuit; and a arithmetic circuit 60 for turning the device 57 on or off according to an on/off control signal from the controller 6, and coercively turning the device 57 off when a current value obtained from a voltage across the resistor 56 exceeds a set current.</p> |
