Hitachi WJ C1 Series User Manual

Chapter 16 Maintenance and Inspection
16-2-2
Inspected
part
Inspected
entry
Details of inspection
Inspection
cycle
Inspection method
Criterion
Tester device
Daily
Every
1 year
2 years
Control
circuit
Protection
circuit
Operation
check
While performing a unit
operation of the inverter,
check the balance of the
output voltage among the
individual phases.
✓
Measure the line voltages
between the [U/T1],
[V/T2], and [W/T3]
terminals of the inverter
main circuit.
Phase-to-phase voltage
balance
200 V class: within 4 V
400 V class: within 8 V
Digital
multimeter,
Ammeter,
Voltmeter
Carry out a sequential
protection test, and
check the protective and
display circuits for any
abnormality.
✓
Simulate a shortcircuit or
open of the inverter
output protection circuit.
An error must be
detected according to the
sequence.
Cooling
system
Cooling fan
Check that there are no
abnormal vibrations or
noises.
✓
Check auditorily and
visually.
Smooth operation. No
abnormality. Wind flows
to the top.
Approximate replacement
period:
10 years
*2*3*5
Check for loose
connections.
✓
Check visually.
Cooling fin
Check for obstrutions/
clogging.
✓
Check visually.
No clogging.
Display
Display
Check if the charge lamp
and the keypad's LEDs
light up.
✓
Check visually.
Check the lighting.
Display cleaning.
✓
With cleaning rag.
External meter
Check that Indicated
values are normal.
✓
Check the meters
readings on the control
panel.
Regulation and control
value are satisfactory.
Voltmeter,
Ammeter,
etc.
Motor
General
Check that there are no
abnormal vibrations or
noises.
✓
Check visually,auditorily,
and by touch.
No abnormality.
Check that there is no
odour.
✓
Check for abnormal
superheating, damages
and so on.
No abnormality.
Insulation
resistance
Check the resistance
between the main circuit
and the ground terminals.
*6
Remove the wiring from
the main circuit terminals
[U/T1], [V/T2] and [W/T3]
of the inverter,
shortcircuit the motor
wire (for 3 phases), and
measure with a megger®
between the motor wire
andthe ground terminal.
No less than 5 MΩ.
500 VDC
class
ohmmeter
(megger®)
*1. The life span of the smoothing capacitor is influenced by the ambient temperature. Refer to
"16.2.5 Smoothing Capacitor Life Curve" for replacing measures.
*2. The life span of the cooling fan is influenced by the ambient temperature, the dirt and the
change in its environmental conditions. Check these circumstances on the usual inspection.
*3. The estimated time before replacement (Number of years/cycle) and the "16.2.5 Smoothing
Capacitor Life Curve" are based on the design lifespan, not guaranteed.
*4. In case using an inverter with a long storage period, perform the following aging before use.
(Aging is not required if the storage temperature is 5 to 35 °C and within 2 years.)
 If the input voltage can be adjusted: Input about 150 VAC for 200 V class and about 300
VAC for 400 V class for about 10 minutes, then gradually input higher value and operate
while checking the functions.
 If the input voltage cannot be adjusted: Input the inverter rated voltage and run for about
30 minutes to check for any problems with the functions. Then, turn on the power again to
perform full-scale operation.
*5. If the cooling fan is locked due to dust, etc., it takes about 5 to 10 seconds to restart even if
dust is removed.
*6. Follow the instruction manual for the motor.

Hitachi WJ C1 Series Specifications

General

Brand	Hitachi
Model	WJ C1 Series
Category	Inverter
Language	English