Power board fault display & trouble shooting
1 Power board fault display instruction
Note: Any of the above fault can led to stop protection and show "welder failure" on the touch screen.
2 Power board fault trouble shooting
If the power board fault occurs, first, check if the alarm displayed. The alarm has 4 types: Mosfet destory, no impulse, over temperature, and working power failure. See above figure. If other components fault, check one by one with the multimeter. Change the component when find out.
2.1 Power board fault and repair
There are 5 indicate LEDs on the two sides of the power board. Normally only 1 green LED is on on each side. When fault occurs, green LED is off, red LED is on.
"Working power fault" LED on-power supply for the power board voltage is less than 15V-check the power supply voltage of the power distribution board.
"Temperature is too high" LED on-the temperature of the aluminum bar for the Mosfet cooling is too high-- inspect if the water channel is smooth.
"Impulse loss" LED on-No impulse input on the power board-check the horn plug cable in the AC main cable output side, and the output cable of the trigger board is well plugged in.
"Mosfet fault"-one or more Mosfet destroy-check the components appearance of the power board. Normally, if the power component is broken, it is featured by shell broken. And check by multimeter other components are ok. The fast recovery diode and large power absorb resitance are to check one by one. When find broken, change it. Remove the power board for maintanance if necessary. Details are referred to "Power board change instruction" and common component measuremnt.
2.2 Power board change instruction
Make sure the power supply is off, the water pump stops before remove the power board!!
Remove the inlet and outlet of the power board. Take measures to prevent the leaking water dripping on the power board. Unplug the impulse and power cable on the sides of the power board. Loose the fixed screw on the DC main bus, then loose the 2 fixed screws on the tank circuit. In this remove process, 2 persons should coperate to prevent power board to fall. Then change a good power board. In the installation, first tighten the screw on the DC main bus not too tightly, fix the 2 tank circuit screws, then tighten the screw on the DC main. After change, check if the cable on the 2 sides of the power board are plugged in and locked. Check the water channel is correct and fixed. When no mistake, the welder can start to work.
