3.2.4
Insulation resistance test using megger
1)
Before performing the insulation resistance test using a megger on the external circuit, disconnect the cables
from all terminals of the power regeneration common converter so that the test voltage is not applied to the
inverter.
2)
For the continuity test of the control circuit, use a meter (high resistance range) and do not use the megger or
buzzer.
3)
For the power regeneration common converter, conduct the insulation resistance test on the main circuit only
as shown below and do not perform the test on the control circuit. (Use a 500VDC megger.)
3.2.5
Pressure test
Do not conduct a pressure test. The power regeneration common converter's main circuit uses semiconductors,
which may be deteriorated if a pressure test is made.
Precautions for Maintenance and Inspection
R/L1
Power
S/L2
supply
T/L3
500VDC
megger
Power regeneration common converter
Ground terminal
33
Inverter
P/L+
N/L-
INV
3