11.0 POSSIBLE WELDING DEFECTS
DEFECT
POROSITY
CRACKS
LIMITED
PENETRATION
HIGH SPRAYS
PROFILE DEFECTS
ARC INSTABILITY
ELECTRODE MELTS
OBLIQUELY
12.0 TROUBLE SHOOTING
INCONVENIENCE
SPARK WILL NOT
START
NO OUTPUT VOL-
TAGE
WRONG OUTPUT
CURRENT
CAUSES
Acid electrode on steel with high
sulphur content.
Electrode oscillates too much.
Workpieces are too far apart.
Workpiece being welded is cold.
Material to be welded is dirty (e.g.
oil, paints, rust, oxides).
Not enough current.
Low current.
High welding rate.
Reversed polarity.
Electrode inclined in position
opposite to its movement.
Electrode is too inclined.
Welding parameters are incorrect.
Pass rate is not related to opera-
ting parameters requirements.
Not enough current.
Electrode core is not centered.
Magnetic blow phenomenon.
CAUSE
Bad primary connection.
Inverter PCB is defective.
Overheated unit, yellow LED lit
Overvoltage protection interven-
tion, green LED off.
Overcurrent protection interven-
tion, yellow LED lit.
Internal relay has failed.
Inverter PCB is defective.
Defective control potentiometer.
Low primary power supply
voltage.
SUGGESTIONS
Use basic electrodes.
Move edges to be welded closer
together.
Move slowly at the beginning.
Lower welding current.
Cleaning workpieces before
welding is an essetial method of
achieving neat weld beads.
Make sure operating parameters
are regulated and improve prepa-
ration of workpieces.
Make appropriate corrections.
Follow basic and general welding
principles.
Check condition of electrode and
earth wire connection.
Replace electrode.
Connect two earth wires to opposi-
te sides of the workpiece.
REMEDY
Check primary connection.
Contact after sales service centre.
Wait for thermal cutout to be reset.
Check power line. Reset the unit
by turning it off and on after 20
seconds.
Reset the unit by turning it off and
on after 20 seconds. If the unit do-
esn't revert working contact after
sales service centre.
Contact after sales service centre.
Contact after sales service centre.
Contact after sales service centre.
Check power line.
EN-9