Circuit; Troubleshooting Diagram - Kemppi Minarc 150 Service Manual

General
This machine may be repaired only by authorized repair shops and persons!
The visual check must be done first, to find possible damages; loose wires, breaks and signs
of overheating.

Troubleshooting diagram

DISTURBANCE
Power source doesn´t start; OCV
~ 0 V;
The power source starts and the
OCV rises up to ~85 V, after
which the power source shuts
down. Th epower source can not
be loaded. The automatic fuses
are blown during start up.
Welding current can´t be adjusted
by potentiometer R001.
POSSIBLE CAUSE
Cooling fan M001
The rectifier diodes are in short

circuit.

Faulty primary circuit power
semiconductor.
Faulty control card A001.
Relay K1
Faulty power adjustment
potentiometer R001.
Fault y control card A001.
REMEDY
Disconnect the fan connector X20
and start the power source again. If
the power source starts and the
OCV is ok, change the fan.
Check the secondary diodes
condition and change if needed. See
the changing of secondary diodes,
page 26.
Check the primary side power
semiconductors. If the voltage over
the PTC R30 is more than ~ 230
Vac then there is a short circuit in
the primary circuit. Change the
faulty power semiconductor. See
the IGBT transistor testing on page
26.
Change the control card A001.
Check the relay operation.
Check the potentiometer condition
(R001 = 10 k )
Ω
Change control card A001.
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