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1. Inspection Before Overhaul
1.1.
Check if the line voltage on the three-phase power supply is within the range of
340V - 420V and, that all phases on a three-phase system are intact.
1.2.
Check if the power cable as well as the earth wire is firmly connected.
1.3.
Check whether the wiring connections are correct and firmly connected.
2. Common Machine Problems and Troubleshooting:
No.
Problem
Root Cause
What to do
1
Machine
is
switched on but
indicator
light
not lit.
One of power supply
phases down.
Check power supply phases
and rectify.
Automatic air switch
damaged.
Replace the automatic air
switch.
Blown fuse.
Replace fuse.
2
Machine
switched
on,
auto air switch
trips
immediately.
Failure of auto air switch.
Replace auto air switch.
IGBT damaged
Replace IGBT and drive circuit
board.
Three-phase bridge
rectifier damaged.
Replace three phase bridge
rectifier
Varistor damaged.
Replace the varistor.
Machine control board
damaged.
Replace the control board.
3
Auto air switch
trips
during
welding
process.
Long-term overload.
Machine to be operated in
accordance with duty cycle.
Auto air switch damaged.
Replace the auto air switch.
4
Welding current
not adjustable.
Broken control cable of
wire feeder or controller.
Replace wire feeder control
cable or the controller.
Control board damaged.
Replace the control board.
Wire at both ends of the
diverter inside the
machine is broken.
Replace the broken wire.
