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Miller xmt 300 electrical troubleshooting

nopoint

Aluminum
Joined
Dec 7, 2009
Location
Wisconsin USA
I have a Miller XMT 300 welder that stopped working. It should probably be replaced with a new machine, but doesn't get a whole lot of use. So I pulled the top cover off to see if there was any visual problems. Such as bulged capacitors, etc. I did find a burnt up component which would be easy to replace if I had any idea what it is. Component has integrated leads and was glued to the case.
IMG_20210407_203711946_HDR.jpg
IMG_20210401_224628936_HDR.jpg
Included my grubby finger pointing at component location as well as in reference to size of part. The component is a bluish color and contains no markings as it is burnt in half.
Any ideas?
Thanks
 
I can’t directly help either but i had major problems with a similar welder. Miller does have repair manuals for their welders. Mine is a pipe pro 304 which is an engine driven xmt basically. It had some burned up components in the same area as yours. I managed to pick up the repair manual on ebay. It’s very detailed and I don’t think I could have fixed my welder without it. The problem is that as far as I know miller doesn’t offer these manuals for sale. There’s a lot going on in an inverter welder . I suggest looking around for such a manual.
 
You can take a pretty good guess when tracing the two wires back to their connection points.

Check the area where the component was lifted from. Is the component the culprit or did some other component blow up and mark up the one in the picture?
(Clean up the inside of the box)
 
I will try and find a manual. The component is connected via two wires and then glued to a support inside the case. It was not integrated to a board. The mystery component was the only thing to visibly fail in that area. Picture was hard to get to turn out. Yes I agree, lots going on inside one of these machines. Thanks for the pointers thus far.
 
Being around electronic components for a few years I have a suggestion:

Looks like the part is not encapsulated but has been wrapped with tape. See if you can unwrap the stuff and discover what is inside.
It is not logical that a little part like that (most likely a protective device) is going to prevent that machine from working again.
 
I managed to pick up the repair manual on ebay. It’s very detailed and I don’t think I could have fixed my welder without it. The problem is that as far as I know miller doesn’t offer these manuals for sale. There’s a lot going on in an inverter welder
 
I managed to pick up the repair manual on ebay. It’s very detailed and I don’t think I could have fixed my welder without it. The problem is that as far as I know miller doesn’t offer these manuals for sale. There’s a lot going on in an inverter welder

It was not integrated to a board. The mystery component was the only thing to visibly fail in that area. Picture was hard to get to turn out. Yes I agree, lots going on inside these machines
 








 
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