Tweco 180 Portable MIG - Manual (Page 55)

MAINTENANCE FABRICATOR 140, 180
July 20, 2007 5-5 Manual 0-4991
5.06 Power Source Problems
FAULT CAUSE REMEDY
1 Primary line voltage is
ON. Welding arc can not
be established.
A Primary fuse is blown. A Replace primary fuse.
B Broken connection in primary
circuit.
B Have an Accredited THERMAL ARC Service Agent check
primary circuit.
2 Primary line voltage is
ON but when the MIG
Gun trigger switch is
depressed nothing
happens.
MIG Gun trigger switch leads
are disconnected.
Reconnect.
3 Primary line voltage is
ON, no wire feed but gas
flows from the MIG Gun
when the torch trigger
switch is depressed.
A Electrode wire stuck in wire
liner or contact tip (burn-back
jam).
A Check for clogged / kinked MIG Gun wire liner or worn
contact tip. Replace faulty component(s).
B Faulty control PCB B Have an Accredited THERMAL ARC Service Agent
investigate the fault.
4 Wire feeds when the MIG
Gun trigger switch is
depressed but arc can
not be established.
Poor or no work lead
connection. Clean work clamp area and ensure good electrical contact.
5 Jerky wire feed A Worn or dirty contact tip A Replace
B Worn feed roller. B Replace
C Excessive back tension from
wire reel hub.
C Reduce brake tension on spool hub
D Worn, kinked or dirty conduit
liner
D Clean or replace conduit liner
6 No gas flow A Gas hose is cut. A Replace or repair.
B Gas passage contains
impurities.
B Disconnect gas hose from the rear of FABRICATOR then
raise gas pressure and blow out the impurities.
C Gas regulator turned off. C Turn on.
7 Gas flow continues after
the MIG Gun trigger
switch has been
released.
Gas valve has jammed open
due to impurities in the gas or
the gas line.
Have an Accredited THERMAL ARC Service Agent repair or
replace gas valve.
Table 5-2: Power Source Problems