55 
 
 
 
Routine examination and periodical examination 
Inverter requires routine and periodical examination and maintenance   
Carry out the examination only after the “ Power LED ” indicator goes off for at least 5 minutes 
 
Examination 
period 
Maintenance 
item 
Maintenance 
description 
Routine 1 Year
 
Examination 
method 
 
 
Criterion 
 
 
Countermeasure
 
Reconfirm environment 
temperature and humidity 
○ 
 
Refer to installation 
instructions and measure 
with thermometer and 
hygrometer 
Temperature: -10~40 
OC Humidity: under 95% 
without condensing 
Installation site 
environment 
Check and remove any 
flammable material nearby 
○ 
 
Visual inspection  No foreign object 
Improve installation 
site environment 
 Is there any abnormal 
 vibration on the installation 
 site? 
○ 
 
 Visual and audio 
 Inspection 
 No foreign object   Tighten loose  
 screw 
  Inverter 
  Installation and 
  Grounding 
Is the grounding resistance 
within acceptable range? 
 
○ 
Measure resistance by 
multi-meter 
200V class under 100 
ohm 
Improve grounding
Input power 
source voltage 
Is the voltage of the primary 
circuitry normal? 
○ 
 
Measure voltage by 
multi-meter 
Voltage level conforming 
specification 
Improve input 
power source 
Is the tighten parts secured?   
○ 
Is there any sign of breakage 
on the terminal panel? 
 
○ 
Inverter 
external 
terminal 
mounting 
screw 
Is there any obvious rusty 
condition? 
 
○ 
Visual inspection. Use 
screwdriver to verify 
screw tightness 
 
No abnormality 
 
Tighten loose screw
or return for repair
 
Is it deformed or skewed?   
○ 
Internal wiring 
of inverter 
Is the insulation of wire 
broken? 
 
○ 
Visual inspection 
 
No abnormality 
 
Replace or return 
for repair 
 
Heat-sink 
Is it accumulating dust or 
dirt? 
○ 
 
Visual inspection  No abnormality  Clean up dust or dirt
Is it accumulating conductive 
metal or oil stain? 
 
○ 
PCB 
Is there any over-heated or 
burnt component? 
 
○ 
Visual inspection 
 
No abnormality 
 
Clean up or replace 
PCB 
 
Is there any abnormal 
vibration or noise? 
 
○ 
Visual and audio 
inspection 
Replace cooling fan
Cooling fan 
Is it accumulating dust or 
dirt? 
○ 
 
Visual inspection 
No abnormality 
 
Clean up 
Power 
component 
Is it accumulating dust or 
dirt? 
 
○ 
Visual inspection  No abnormality 
 
Clean up 
Is there any sign of strange 
order or leakage? 
○ 
 
Capacitor 
Is there any sign of swelling 
or bulging? 
○ 
 
Visual inspection  No abnormality  Replace capacitor 
or inverter