Welders Chime In Please!, Lincoln weld pak 100 shorts where wire enters gun! Options

[Jeffs9146]

Lennies914 is in the field welding on a large CoGeneration system and is having problems with the welder. The system is built into a building and wired into the electrical system. The welder is pluged into the wall and the CoGen unit is shut off.

When the welder ground is attached to the CoGen unit and he attempt to weld the wire heats up inside the feeder and the wire melts and balls up! If he disconnects the ground the wire feeds fine. I used this welder a week ago and it worked great at my house!

The question is:

What would cause this? Would the fact that the CoGen system is grounded to the same plug that the welder is pluged into cause a problem? If a battery is hooked to the CoGen system would that cause this problem? OR Is there anything else that may cause this problem?

[stugray]

The inside of a wire feeder is isolated from the outside world.

The internal mechanism with the feed wheels must not be electrically connected to the wire feeder housing because the entire mechanism is at the same potential as the weld wire.

Something inside the feeder must have shorted to the housing.

Try setting the feeder up on a piece of plastic and try it again.

If the wire melts the same way, then the short is inside the welder power supply part.

HTH

Stu