5- 2
5.2 Daily and annual maintenance
Item Contents
Method Criteria
Ambient
Environment
Check ambient temperature,
humidity, dust, corrosive gas, oil
mist, etc.
X
Refer to
2.1. Installation
Ambient temperature:
-10 ~ +50°C (no icing)
No condensation
Devices
overall
Check for abnormal vibrations
and noise.
X Visual inspection No abnormalities
Overall
Power supply
voltage
Check voltage between
input lines
X
Measure the voltage between
input terminals
No abnormalities and
Overall
Megger check
(Power terminal - Earth)
X
Remove connector J61
Disconnect power line
Remove logic terminal
Make short circuit R, S, T, U,
V, W, P, PD ,N ,RB
Megger test between above
and earth
> 5Mohm
Check installation for looseness.
Tighten No abnormalities
Check for evidence of over
heating in the various
components
X Visual inspection No abnormalities
Cleaning X
Conductors /
cables
No change in shape? X Visual inspection No abnormalities
No damage in coating?
Visual inspection No abnormalities
No damage?
Visual inspection No abnormalities
Mains
Inverter /
Converter
Tester check between each
terminal
X
Remove power cables
Measure resistance;
Each input ⇔ P, N
Each output ⇔ P, N
with 1ohm range
Refer to
“5.5 How to measure
inverter &
converter“ portion
DC bus capacitor Check for leaking liquid X Visual inspection No abnormalities
Check for swelling
Visual inspection No abnormalities
Check for capacitance X With capacitance meter
85% or more of rated
capacitance
Relay, contactor
Check for stuttering noise during
operation
X Aural inspection No abnormalities
No damage of contact?
Visual inspection No abnormalities
Resistors
Check for cracks or
changes in color
X Visual inspection No abnormalities
No open circuit? X Tester check
Tolerance of within
±10% of rated value
Cooling fan
Check for abnormal
vibration and noise
X
Rotate manually
during power off
Smooth rotation and
no abnormalities
Cooling
Check for dust
Visual inspection No abnormalities
Operation check
Check the balance of the output
voltage of each phase to phase
without motor.
X
Measure the output voltage
between U, V and W
Within 2% of voltage
difference between
each phases.
Control circuit
Perform a sequence protection
operation test and make sure
that there are no errors in the
protection and display circuits.
X
Simulate operation of the
protection circuit
Each protection should
be performed
Display
No illegible display;
No missing characters;
No segment failure of LEDs
X Visual inspection No abnormalities
Cleaning
LED
display
Meter Working correct? X X Visual inspection Displays correct value
Overall
No abnormal vibration & noise?
Visual, aural inspection No abnormalities
No abnormal smell? X
Confirm the smell caused by
overheat, damage etc.
No abnormalities
Motor
Insulation
resistance
Megger check
All terminals together - Earth
X
Measure resistance;
Each input ⇔ Earth
cables
> 5Mohm
