Maintenance; Safety Precautions; Routine And Periodic Maintenance; Overload Protection - Lincoln Electric PRECISION TIG 275 Operator's Manual

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SAFETY PRECAUTIONS

WARNING
ELECTRIC SHOCK can kill.
• Only qualified personnel should
perform this maintenance.
• Turn the input power OFF at the
disconnect switch or fuse box
before working on this
equipment.
• Do not touch electrically hot
parts.
WARNING
To avoid receiving a high frequency shock, keep the
TIG torch and cables in good condition.

ROUTINE AND PERIODIC MAINTENANCE

Very little routine maintenance is necessary to keep
your Precision TIG 275 running in top condition. No
specific schedule can be set for performing the follow-
ing items; factors such as hours of usage and machine
environment should be considered when establishing
a maintenance schedule.
• Periodically blow out dust and dirt which may accu-
mulate within the welder using an air stream.
• Inspect welder output and control cables for fraying,
cuts, and bare spots.
• Inspect the spark gap at regular intervals to maintain
the recommended spacing. See the Service
Procedures (See Service Procedures in this
Section) for complete information on spark gap set-
tings.
• The fan motor has sealed ball bearings which
require no maintenance.

Overload Protection

MAINTENANCE

OVERLOAD PROTECTION
FAN-AS-NEEDED (F.A.N.)
The Precision TIG 275 has the F.A.N. circuit feature,
which means the cooling fan will operate only while
welding; then for about 8 minutes after welding has
stopped to assure proper machine cooling. This helps
reduce the amount of dust and dirt drawn into the
machine with the cooling air. The cooling fan will oper-
ate briefly when the machine power is initially turned
on, and continuously while the yellow Thermal
Shutdown Light is lit (see Thermostatic Protection).
THERMOSTATIC PROTECTION
This welder has thermostatic protection from excessive
duty cycles, overloads, loss of cooling, and excessive
ambient temperatures. When the welder is subjected
to an overload, or inadequate cooling, the primary coil
thermostat and/or secondary coil thermostat will open.
This condition will be indicated by the illumination of
the yellow Thermal Shutdown Light on the front panel
(see Item 10 in Section B). The fan will continue to run
to cool the power source. Postflow occurs when TIG
welding is shut down, but no welding is possible until
the machine is allowed to cool and the yellow Thermal
Shutdown Light goes out.
AUXILIARY POWER CIRCUIT BREAKER
The 115vac auxiliary circuits and rear receptacle (see
Section A Auxiliary Power Connections) are protected
from overloads by a 15 amp circuit breaker, located
above the receptacle. If the breaker trips its button
pops out exposing a red ring. When the circuit breaker
cools the button can be reset by pressing it back in.
Note: When the breaker trips not only will the recepta-
cleʼs auxiliary and cooler power be interrupted, but so
will the power to the shielding gas solenoid and
machine cooling fan.
The Export models also include a 5 amp circuit break-
er, located on the opposite side of the upper case back,
for protection of the 220vac Schuko type cooler recep-
tacle.
PRECISION TIG 275
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