Tig Welding - Lincoln Electric SQUARE WAVE IM467-B Operator's Manual

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TROUBLESHOOTING GUIDE
SYMPTOM
Machine does not respond (no gas flow, no
high frequency, no open circuit voltage) when
Arc Start Switch or Amptrol is pressed.
No gas or water flow when Arc Start Switch
is closed in TIG mode.
No High Frequency.
Weak high frequency.
Machine shuts down (pilot light goes out
and fans stop) when Arc Start Switch or
Amptrol is pressed.
Cannot preset a current on Ammeter when the
Arc Start Switch or Amptrol is not pressed.
TROUBLESHOOTING

TIG WELDING

1. Defective Arc Start Switch or Amptrol. Check for con-
tinuity between pins D and E on cable connector when Arc
Start Switch or Amptrol is pressed.
2. Defective Protection PC board. Replace.
3. Defective Control PC board. Replace.
1. Gas supply is empty or not turned on.
2. Pinched gas or water hose.
3. Gas and High Frequency fuse (F2) blown. Replace fuse.
4. Gas and High Frequency fuse (F2) is too small. Use 1.5 amp
fuse.
5. Gas and water lines or solenoids are blocked with dirt. Clean
out and use filters to prevent recurrence.
6. Power PC board is defective. Replace.
1. High Frequency switch S12 must be in either START or
CONTINUOUS position for high frequency to function.
2. Preflow control is set too long. Reduce Preflow setting. (High
Frequency does not come on until end of preflow period.)
3. Gas and High Frequency fuse (F2) blown. Replace fuse F2.
4. Gas and High Frequency fuse (F2) is too small. Use 1.5 amp
fuse.
5. Spark Gap is too large. Set to gap specified on cover plate.
6. Power PC board is defective. Replace.
1. Spark gap is set too close. Set to 0.015 inches (0.381 mm)
gap for most applications.
2. High Frequency Intensity control set too low. Increase to suit.
3. Work and electrode cables in poor condition, allowing high
frequency to "leak" to ground. Use good quality cables,
preferably those with a high natural rubber content, as short
as possible.
4. No shielding gas. Adjust gas flow for 10 to 30 CFH (4.7 to
14.1 l/min.) for most applications. (High frequency will not
jump from the tungsten to the work without shielding gas.)
1. If open circuit voltage is greater than 80 volts before shut-
down occurs, Control PC board is defective. Replace.
Defective Arc Start Switch. There should be no continuity
1.
between pins D and E of cable connector when Arc Start
Switch or Amptrol is not pressed.
2. Defective Current Control potentiometer. Replace.
3. Defective Control PC board. Replace.
4. Defective Feedthrough PC board. Replace.
SQUARE WAVE TIG 355
Observe Safety Guidelines
detailed throughout this manual.
CAUSE AND REMEDY
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