I want to add a amp meter (temp) to my Lincoln SP-135T mig to see just what the output current is on any given setting while I am welding. I am thinking of adding a 200A shunt resistor in the output line to the tip and reading across it with a digital meter. ( I will get someone to read the meter) My question is - has anyone tried this or something like this?
- Thread starter Jackson
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rtbcomp
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It may be possible to measure the resistance of the earth return lead and put a voltmeter accross that, depends on the length & thickness of the cable.
If you want to use a shunt, it would be easier to fit in the earth lead.
You could try a clamp meter, but get one that reads direct current.
If you want to use a shunt, it would be easier to fit in the earth lead.
You could try a clamp meter, but get one that reads direct current.
SirDick Diodenob esquire
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Using a shunt to measure the dc output from a TIG is very common in older machines ( maybe in newer ones as well ? ) , the photo is a 400amp shunt fitted to a Newarc TIG , Murex TIG welders used a similar set up , in both cases to provide the control circuit with a voltage reading proportional to current . I would expect the output from a mig to be all over the place , would be interested to see what result you get , also agree as rtbcomp said its just as valid to use the earth return lead as a shunt depends how accurately you can measure the very low resistance of it and then calculate the current from the volt drop accross it .
