Firepower MST 140i, Operating Manual

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Firepower MST 140i
Manual 0-5338 5-1 TROUBLE SHOOTING AND SERVICE
SECTION 5:
POWER SOURCE PROBLEMS AND ROUTINE SERVICE REQUIREMENTS
5.01 Power Source Problems
FAULT CAUSE REMEDY
1 Primary Power Supply is
ON, power indicator is illu-
minated however the Power
Source will not commence
welding when the torch trig-
ger switch is depressed.
A Power Source is not in the correct
mode of operation.
A Set the Power Source to the cor-
rect mode of operation with the
process selection switch.
B Welding leads, or polarity cable
not connected.
B Connect welding leads or polar-
ity cable.
C Faulty torch trigger. C Repair or replace torch trigger
switch/lead.
2 Fault Indicator is illuminat-
ed and the Power Source
will not commence weld-
ing when the torch trigger
switch is depressed.
Duty cycle of Power Source has
been exceeded.
Leave the Power Source
switched ON and allow it to cool.
Note that fault indicator must
be extinguished prior to com-
mencement of welding.
3 The Power Source will not
feed wire in MIG mode.
A Electrode wire stuck in conduit
liner or contact tip (burn-back
jam).
A Check for clogged / kinked MIG
Gun conduit liner, loose nozzle
or worn contact tip. Replace
faulty components.
B 8 pin gun connector not con-
nected.
B Connect 8 pin gun connector.
C Faulty torch trigger. C Repair or replace torch trigger.
D Wire tension too loose. D Tighten wire tension.
E Brake tension too tight. E Loosen brake tension.
4 Welding wire continues to
feed when torch trigger is
released.
A Trigger mode selection switch is in
4T latch mode.
A Change the trigger mode selec-
tion switch from 4T latch mode
to 2T normal mode.
B Torch trigger leads shorted. B Repair or replace torch trigger
switch/lead.
5 Welding arc cannot be
established in MIG mode.
A MIG Gun polarity lead is not
connected into a welding output
terminal.
A Connect the MIG Gun polar-
ity lead to either the positive
welding output terminal or the
negative welding output terminal
as required.
B Poor or no work lead contact. B Clean work clamp area and en-
sure good electrical contact.
6 Inconsistent wire feed. A Fouled contact tip. A Replace contact tip if necessary.
B Drive roll tension not tight enough. B Tighten drive roll tension.
C Worn feed roll.
C Replace.
D Excessive brake tension on wire
reel hub.
D Reduce brake tension on spool
hub
E Worn, kinked or dirty conduit liner. E Clean or replace conduit liner