Heads Up on Proper Grounding (Miller Multimatic 215)

[Janderso]

So, Mr. bear,
I assume you do not recommend just grounding the table.
I don’t have the experience to make the following assumption but here I go.
If the piece has full contact, a large area to transfer a grounded point, the table ground would be adequate.
If an angled piece with just a few points on the table, best to ground the piece.
Imho

 

[Buffalo21]

Poor grounds are common, at least for me. I beter stick (pun intended) to transformer technology I guess.

Greg

According to my BIL, a MIller tech, that if a bad ground caused the problem, that would be a major design flaw in the welder, as loose or bad grounds are one of the most common issues with a welder. He said the customer should call Miller’s customer service and describe the issue, because if it was an issue of any kind, there would be numerous service bulletins., which he said he has never seen.

 

[Ray C]

According to my BIL, a MIller tech, that if a bad ground caused the problem, that would be a major design flaw in the welder, as loose or bad grounds are one of the most common issues with a welder. He said the customer should call Miller’s customer service and describe the issue, because if it was an issue of any kind, there would be numerous service bulletins., which he said he has never seen.

I'm really glad you said this because I've been watching this post and scratching my head. I do a fair bit of welding and have lost ground more times than I can count with no less than 4 different welding units. It usually happens when I switch cable sets and connect the wrong ground clamp to the table stud. I've had plenty of weak grounds from not cleaning the table or getting enough of the scale off the subject piece. This has never caused a problem with the equipment.

If the machine sees a lot of use, maybe something just went bad due to natural failure. -It happens... -Nothing mechanical or electrical is perfect forever.

Ray

 

[682bear]

So, Mr. bear,
I assume you do not recommend just grounding the table.
I don’t have the experience to make the following assumption but here I go.
If the piece has full contact, a large area to transfer a grounded point, the table ground would be adequate.
If an angled piece with just a few points on the table, best to ground the piece.
Imho

Keep in mind that any contamination, paint, dirt, oil, mill scale, dust, or just about anything else between your work and table will also increase the resistance in the circuit... potentially leading to the same problem.

I have my table permanantly grounded to the welder and also use a spring clamp directly to the work (if the work is big enough to use the clamp on). You can't be grounded too well...

-Bear

Post #7...

-Bear