| 摘要 |
PURPOSE: To avoid the decline of the insulation resistance between a car body and a power line by a method wherein a control means controls a switch means and, when a leak is detected, a leak detecting means is electrically connected to a power supply line and, while a leak is not detected, the leak detecting means is not electrically connected to the power supply line. CONSTITUTION: A switch means which is composed of switches SW1 and SW2 and switches between the connection state and the open state between a leak detecting circuit 104A and power supply lines L1 and L2 is provided in the leak detecting circuit 104 which is provided between a battery 101 and a first relay 103. One of the terminals of the leak detecting circuit 104A is connected to a car body through a resistor R. A control unit 108A detects a leak and gives alarm, etc., and, further, controls the ONs/OFFs of 1st, 2nd and 3rd relays 103, 105 and 107 and monitors the states of the relays and, moreover, controls the switches SW1 and SW2 of the switch means. |
