Miller Electric CST 250 VRD manual Use proper size and type of weld cable see Section

Trouble	Possible Causes	Remedy
Erratic or improper weld output.	Weld cable too small or defective.	Use proper size and type of weld cable (see Section 3-6).
	Dirty or loose connections.	Clean and tighten all weld connections (see Section 3-6).
Wandering arc	Improper size tungsten.	Use proper size tungsten (see Section 7).
	Worn or defective tungsten.	Use properly prepared tungsten (see Section 7).
	Shielding gas flow too high.	Reduce shielding gas flow rate (see Section 3-7).
Tungsten electrode oxidizing and not	Shielding gas blown away from weld	Shield weld zone from drafts.
remaining bright after conclusion of	zone.
weld.
	Inadequate postflow time.	Allow adequate postflow time to shield tungsten while it
		cools, after welding stops.
	Loose or leaking gas fittings.	Check and tighten all gas fittings (see Section 3-7).
	Water in torch.	Refer to torch manual.

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