19
Appendix A: common failures, probable cause & countermeasures
№
Phenomena
Reason
Solving
methods
1
After power on, it
doesn’t work.
Phase missing power source, in
Fuse
（
2A
）
in welder is broken.
Cable is broken
Check power source
Check if cooling fan,
power source transformer
and main control board are
good or not.
Check connection
2
Air switch on
back panel trips
while the
machine is
working
normally.
The following components may be
damaged: IGBT module, 3-phase
rectify module, outputting diode
module, or other components, Driving
board is damaged.
Short circuit between lines.
Check and replace.
When IGBT module is
damaged, please check
12
Ω
, 5.1
Ω
resistance or
SR160 on driving board is
damaged or not.
3 Welding
current
is unstable.
Phase missing
The following components may be
damaged
：
Potentiometers, switches
on front panel and remote control
cable, potentiometer on remote
controller.
Main control board is damaged
Check power source.
Check and replace.
4 Welding
current
is not adjustable.
Potentiometer of welding current
adjustment is damaged.
Remote control cable is broken.
Main control board is damaged
The switch on the front panel is
damaged
Check and replace.
5
TIG welding is
abnormal.
TIG torch switch is damaged.
Remote control cable is broken.
The tungsten electrode in welder is in
the wrong position.
Main control board is damaged
Check and replace.
