Lincoln Electric IM904 manual Problems Symptoms Possible Cause

E-6	TROUBLESHOOTING	E-6
	Observe Safety Guidelines detailed in the beginning of this manual.

PROBLEMS (SYMPTOMS)

POSSIBLE

CAUSE

OUTPUT PROBLEMS

RECOMMENDED COURSE OF ACTION

Porosity in the weld	1.	Make sure proper gas type and
		flow rate is correct for procedure
		being used. Shield work from
		excessive outside air currents.
	2.	Check gun and nozzle for leaks
		or obstructions.
	3.	Make certain machine and wire
		feed settings are correct for
		process.
Weld bead appears “cold”.	1.	One or more of the machine set-
		tings may be wrong. Check the
		Background, Peak Current,
		Tailout and wire speed controls
		for proper settings. Adjust for
		optimum welding performance.
	2. Make sure the Wire Type, and
		Wire Size switches are in the cor-
		rect position for the electrode
		wire being used.
Molten weld puddle appears exces-	1.	The Wire Type switch may be in
sively “violent”.		the wrong position for the elec-
		trode wire being used.
	2.	The Peak Current setting may be
		too high. Adjust for optimum
		welding performance.

If all recommended possible areas of misadjustment have been checked and the problem persists,

Contact your local Lincoln Authorized Field Service Facility.

CAUTION

If for any reason you do not understand the test procedures or are unable to perform the tests/repairs safely, contact your Local Lincoln Authorized Field Service Facility for technical troubleshooting assistance before you proceed.

INVERTEC STT II (CE)