Troubleshooting; Possible Cause - LORCH LTG 900 Bedienungshandbuch

8

Troubleshooting

Problem
Arc is not ignited
Torch body or power
supply is overheating
Gas shielding is bad
Tungsten Electrode
damaged
- 24 -

Possible cause

– interrupted power supply to work
piece and/or torch
– torch is wet
– electrode of torch is highly oxi-
dized (grey)
– impurities in shielding gas (mois-
ture, air)
– ignition spark is 'escaping' from
elsewhere and not from elec-
trode of torch
– switch cable interrupted
– power supply control system not
functioning properly
– inadequate flow of coolant
– fault in coolant cable or liquid-
cooled power cable
– electrode is loose
– too much welding flow
– impurities in shielding gas (mois-
ture, air)
– impurities in base material (rust,
base coat, grease)
– inadequate shield gas coverage
– net of gas lens is damaged
– excessive current level
– moisture in torch
– plasma gas flow rate to low
– electrode touching work piece
Troubleshooting
Solution
– close power circuit
– dry torch
– sharpen again lengthwise and
clean
– check quality shielding gas
– grinding electrode
– gas check
– exchange switch cable
– repair power supply; see
operating instructions power
supply
– check circulating coolant unit
– check flow and replace cable
if necessary
– tighten with back cap
– reduce flow
– check quality gas
– clean base material
– increase flow
– replace
– reduce current or use larger
electrode
– check o-rings for coolant
leaks; check gas hoses
– increase flow rate
– increase stand off (after
grinding work piece and elec-
trode)
10.12