MG125-4 PEGAS 200 AC-DC PULSE SERVICE MANUAL
page 6
ALFA IN a. s. © 2012
SERVISNÍ TECHNICKÁ DOKUMENTACE
Gas cylinder is close or
gas pressure is low
Open or change the gas cylinder
Something in the valve
Remove it
8
No gas flow (TIG)
Electromagnetic valve
is damaged
Change it
The gas-test on the
front panel is on
The gas-test on the front panel is off
Something in the valve
Remove it
Electromagnetic valve
is damaged
Change it
9
Gas always flows
The adjustment knob of
pre-gas time on the
front panel is damaged
Repair or change it
10
The welding current can not be adjusted
The welding current
potentiometer on the
front panel connection
is not good or damaged
Repair or change the potentiometer
The power PCB is in
trouble.
Repair or change it.
The AC drive PCB
damaged.
Change it.
11
No AC output while selecting “AC”
The AC IGBT module
damaged.
Change it.
The min value
displayed isn’t
accordant with the
actual value. (Please
refer to
§
3.1)
Adjust potentiometer Imin on the
power board.
12
The welding current displayed isn’t
accordant with the actual value.
The max value
displayed isn’t
accordant with the
actual value. (Please
refer to
§
3.1)
Adjust potentiometer Imax on the
power board.
The welding current is
adjusted too low
Increase the welding current
13
The penetration of molten pool is not
enough.
The arc is too long in
the welding process
Use 2T operation
Two much
welding
current
Reduce the welding current output
Over
heat
protecti
on
Working time
too long
Reduce the duty cycle (work
intermittently)
Over-
voltage
protecti
on
Power
supply
fluctuates
Using the stable power supply
Power
supply
fluctuates
Using the stable power supply
Low-
voltage
protecti
on
Too many
machines
using power
supply in the
same time
Reduce the machines using power
supply in the same time
14
The alarm light on the front panel is on
Over-
current
protecti
on
Unusual
current in the
main circuit
Check and repair the main circuit
and drive Pr6
