Kemppi MASTERTIG AC/DC 2500W, Service Manual

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TECHNICAL SERVICE MANUAL FOR MASTERTIG ACDC
TROUBLESHOOTING CHART
PROBLEM CAUSE REMEDY
Porosity in the weld joint. Shield gas flow is not correct,
leakage in the gas hose or faulty
solenoid valve. Check the gas flow; adjust correct
flow according welding parameters
or repair faulty component in gas
flow system.
No HF ignition Faulty control card A004.
Broken HF-transformer T003.
During HF ignition the voltage from
connector X1/1 and X1/3 should be
about 1kV. You can also check the
control signal of microprocessor from
connector X2/2 which is located
between panel and PCB A002.
If the voltage from PCB is all right
change the HF-transformer T003.
Welding characteristics are bad
when welding method is
AC TIG .
Additional pulse to ignite the positive
half cycle is missing. Check the function of control card
A003. The pulse circuit driving
component is small IGBT V47.
Check and change the IGBT if
needed.
Positive or negative half cycle is
missing, or both are missing.
Machine is creating high pitched or
rattling sound.
Faulty control card A002 or A003.
Faulty IGBT in primary or secondary
inverter.
Faulty gate IGBT connection in
control card A002 or A003.
Check that control of selecting
welding method is working from the
PCB A003, see
PICTURE 1.
Check according following text;
Primary inverter is VG 101.
When the current goes through
VG201 the method is DC+. If the
current goes through VG202 the
method is DC-. When the current
goes through both of them the
method is AC.
See also PICTURE 4.
If security code is in use and panel is
locked. Wrong security code. The locked panel can be unlocked at
an authorised KEMPPI service repair
shop with a special code . The
unlock code is available only in
these places.
Maximum positive or negative
current adjustment is incorrect. Wrong/changed adjustment in
control card A002. Maximum positive and negative
current can adjust from A002, see
also
PICTURE 2.