Maintenance
‑90‑
Inspection Item Description Solution Checked
Peripheral devices such
as electromagnetic
contactor
● Check devices for loose connection
and abnormal noise during
operation.
● Check peripheral devices for short
circuit, water stains, swelling, and
cracks.
Replace abnormal peripheral
devices.
Ventilation
● Check whether ventilation and
heatsink are clogged.
● Check whether the fan is damaged.
● Clean the ventilation.
● Replace the fan.
Control circuit
● Check control elements for loose
contact.
● Check for loose terminal screws.
● Check control cables for cracked
insulation.
● Clear foreign matters on the
surface of control cables and
terminals.
● Replace damaged or corroded
control cables.
9.2 Main Circuit Insulation Test
Do not conduct high voltage (> 500 V) tests, which are already done before delivery.
Before testing, remove the VDR screw and disconnect the VDR.
Before measuring insulation resistance with a megameter (500 VDC megameter
recommended), disconnect the main circuit from the AC drive first. Do not measure
the control circuit insulation resistance with an insulation resistance meter.
The insulation resistance measured must be greater than 5 MΩ.