Fault and maintenance of inverter welding machine

The problem of inverter welding machine without output voltage and related solutions are as follows:

First check whether the input power supply is normal, whether the contactor or air switch is normal, and whether the internal main circuit part is open. If there is nothing wrong with the main circuit, check whether the driving circuit of the control circuit igbt is normal.

Determine whether the DC output of 220V rectifier bridge is normal, which should be around D250V.

First, disconnect the DC voltage of DC250V, and measure the G pin of each inverter MOS tube to see if there is a driving voltage. If yes, check MOS tube and output rectifier fast recovery diode; If not, check the relevant circuit of the control panel.

Check whether the back stage of the welder is short-circuited, so that the whole circuit is protected.

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Overheating protection of welding machine;

When the welding machine is in normal use, the power switch tube and rectifier diode will be overheated and damaged due to the large working current or the poor heat dissipation of the fan (blocked by dust and sundries). Therefore, general inverter welding machines are equipped with overheating protection. When the temperature reaches a certain value, the power output of the welding machine will be limited or the welding machine will stop directly to give an indication of overheating protection. Avoid the expansion of problems, such as tube explosion.