5.3 Megger test

Disconnect all the wiring in case of megger test on external circuit, so that no test voltage is supplied to the inverter. Use tester (high resistance range) for the test of control circuit. Do not use megger nor buzzer.

Megger test should be done only on the power (mains) portions. Do not perform megger test on control circuits. (Use DC500V megger in case of megger test.)

In case of megger test on power terminals, disconnect short circuit material at connector “J61” located close to R0T0 terminal, and connect R, S, T, PD, P, N, RB, U, V and W all together. Connect again the short circuit material to J61 after the test is done.

Power supply

There must be no power supply

connected

DC500Vmegger

P P N R

RU

SV

TM

J61

Earth terminal

Motor

IM

There must be no connection to the motor.

Be sure to disconnect the short circuit

material for the megger test.

5.4 Withstand voltage test

Do not perform withstand voltage test.

Semiconductors that are used in inverter can be degraded when withstand voltage is performed.

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Hitachi L300P Series service manual Megger test