4-3 Megger Test 4-3 Megger Test For a megger test of the external circuit, be sure to disconnect all the terminals of the Regenerative Braking Unit, so as not to apply the test voltage to the Regenerative Braking Unit. Use a high resistance tester for a power distribution test of the control circuit. Do not use a megger or buzzer. Conduct a Regenerative Braking Unit megger test only to the main circuit, not to the control circuit. Use a 500 V DC megger for a megger test. Gradually increase the applied voltage, and reduce it to 0 V. To conduct a megger test for the main circuit, short-circuit the P, RB and N terminals with a wire.
4 Regenerative Braking Unit P RB Inspection and Maintenance N 500 V DC megger Ground terminal Applied voltage Applied voltage Time Time 0.1 s min. 0.1 s min. Note: Do not connect the power cable. 4-4