OWNER’S MANUAL - 18 -
TROUBLESHOOTING AND FAULT FINDING
Notes: The following operations must be performed by qualified electricians with valid certifications. Before
maintenance,please contact with us for professional suggestion.
MIG 500 fault symptom and solution.
Fault symptom
Solution
Power Indicator lamp off
No running of air fan
No power supply output for welding
1. Confirm the air switch closed.
2. Power supply available for input cable.
3. Confirm power supply without and phase lacking.
Power Indicator lamp off
Air fan operates normally
But no power supply output for welding
A failure in auxiliary power component of control board. (Please contact
with the dealer or the factory).
Abnormity Indicator lamp on
Power Indicator lamp on
Air fan operates normally
1. IGBT damage.
2. Fast-recover rectifier damage.
3. Control board failure.
Air fan operates normally
Power Indicator lamp on
But no power supply output for welding
1. Check all plug wires or connection joints inside the machine if they have
bad contact.
2. Control wire of weld gun has been broken or its micro-switch damaged.
3. Control circuit failure (Please contact to the dealer or the factory).
Air switch not to be closed
1. Defective quality of the air switch.
2. Three-phase rectifier bridge failure, please replace it.
3. Inspect if there is any short circuit failure in the machine.
