ANDELI MCT Series Owner's Manual page 19

Tungsten needle burnt seriously
Can not break the oxide film when
welding aluminum
and replaced.
(2) If the abnormal indicator does not light:
a. It may be damaged in the middle plate transformer. The primary
inductance and Q value of the main transformer can be measured by
the bridge.
b. It may be that the transformer secondary rectifier is individually
broken down, and the same type of rectifier is found and replaced.
4. It may be that the feedback circuit is open.
The duty cycle is adjusted too much to reduce the duty cycle.
1. The welding gear selection is incorrect;
2. The duty cycle adjustment is too small;
3. The secondary inverter has field tube damage.
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