5-7 
5.3 Troubleshooting of the Inverter 
5.3.1 Quick troubleshooting of the Inverter 
INV Fault
Visually check controller 
and Drive boards
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Check burnt and 
damaged parts
 Consult with the supplier
Replace fuse
  Consult with the supplier
   Consult with the supplier
Check according to 
displayed fault messages
Replace the pre-charge 
resistor
Check terminals and 
wiring
  Consult with the supplier
Perform detailed check and 
consult with the supplier
Is fault known?
Symptoms other than burn 
out, damage, or fuse 
meltdown in the inverter?
Any Symptoms of burn 
out and damage?
Is the main circuit DM 
intact?
Fault signal?
Is the fuse intact?
Is the main circuit 
I.G.B.T intact?
Any visual 
abnormalities?
Are displays and 
indicators of the 
operating unit working 
normally?
Is +5V control voltage 
correct?
Is the DC input voltage 
controlling the power 
correct
Any fault display?
What  the message  ?
Is LED lit?
Replace control board 
and digital operating unit
Is the error eliminated 
after replacing control 
board?
YES
NO
NO YES
NO
NO
NO
YES
YES
YES
YES
NO
NO
NO
YES
YES
YES
YES
NO
NO
YES
NO
YES
NO
YES
NO
YES
NO
Apply the power