Thermal Arc C/W VFE 4C HS III, Operation Manual

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10.03 Welding Problems (continued)
FAULT CAUSE REMEDY
6 Weld cracking. A. Weld beads too small
B. Weld penetration
narrow and deep
C. Excessive weld
stresses
D. Excessive voltage
E. Cooling rate too fast
A. Decrease travel speed
B. Reduce current and voltage
and increase Mig torch travel
speed or select a lower
penetration shielding gas.
C. Increase weld metal
strength or revise design
D. Decrease voltage by
reducing the voltage selection
switches.
E. Slow the cooling rate by
preheating part to be welded
or cool slowly.
7 Cold weld puddle. A. Faulty rectifier unit
B. Loose welding cable
connection.
C. Low Primary Voltage
A. Have an Accredited
THERMAL ARC Service Agent
to test then replace the faulty
component.
B. Check all welding cable
connections.
C. Contact supply authority
8 Arc does not have
a crisp sound that
short arc exhibits
when the wirefeed
speed and voltage
are adjusted
correctly.
The MIG torch has been
connected to the wrong
voltage polarity on the
front panel.
Connect the MIG torch to the
positive (+) welding terminal
for solid wires and gas
shielded flux cored wires.
Refer to the electrode wire
manufacturer for the correct
polarity.
10.04 Power Source Problems
FAULT CAUSE REMEDY
1 Indicator light is
ON but welding
arc can not be
established.
Voltage switch in
standby position.
Switch the voltage selection
switches to a welding
setting.
2 Mains supply
voltage is ON.
Indicator light is
not lit and welding
arc can not be
established.
A. Primary fuse is
blown.
B. Broken connection in
primary circuit.
A
B
Replace primary fuse. Have
an Accredited THERMAL
ARC Service Agent check
primary circuit.
3 Mains indicator
light is not lit but
welding arc can be
established.
Indicator light is open
circuit.
Have an Accredited
THERMAL ARC Service
Agent replace Indicator
light.
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