109
9
9.2.2 Insulation Test on Main Circuit
Inspection Item Inspection Points
Inspection Points
Checked
General
Inspect for wastes, dirt and dust
on the surface of the AC drive.
Check that the AC drive is powered off.
Use a vacuum cleaner to suck up wastes
and dust to avoid direct contact.
Wipe surface dirt gently with a soft cloth
immersed in neutral detergent.
Cables
Inspect power cables and
connections for discoloration.
Inspect wiring insulation
for aging or wear.
Replace cracked cables.
Replace damaged terminals.
Peripheral
devices such
as relay and
contactor
Inspect contactors and relays for
excessive noise during operation.
Inspect coils for signs of
overheating such as melted or
cracked insulation. Check whether
the coil voltage is normal.
Replace abnormal peripheral devices.
Ventilation
Inspect whether ventilation
and heatsink are clogged.
Check whether the fan
is damaged.
Clean ventilation.
Replace the fan.
Control circuit
Inspect for control components
with poor contact. Inspect for
loose terminal screws. Inspect
for control cables with cracked
insulation.
Clear away foreign matter on the surface
of control cables and terminals.
Replace damaged or corroded control cables.
Before measuring insulation resistance
with a megameter (a 500 VDC megameter
is recommended), disconnect the main
circuit from the AC drive. Do not conduct the
dielectric strength test using an insulation
megameter. High voltage (> 500 V) test need
not be performed again because it has been
completed before delivery.
The measured insulation resistance must
be greater than 5 MΩ.
Before test, remove the VDR screw.
For positions of VDR and EMC screws,
refer to Figure 5-2-3f in Electrical Wiring.
Figure 9-2-2 Test insulation on the main circuit
9.3 REPLACEMENT OF WEAR PARTS
9.3.1 Lifetime of Wear Parts
Component
Service Life
Fan
≥ 5 years
Electrolytic capacitor
≥ 5 years
You can determine when to replace these
parts according to the actual operating time.
1. Ambient temperature: 40°C
2. Load rate: 80%
3. Operating rate: 24 hours per day
DC 500V
Megameter
BR
P
+
-
+
-
R
S
T
U
V
W
Benshaw PowerPro
™
High Performance
Single AC Drive
