General welding questions that dont fit in TIG, MIG, Stick, or Certification etc.
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curly84
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Converting a ac welder to dc via 300 amp rectifier, my question is will this be dc positive or dc negative thanks in advance

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It will only depend on where you hook your cables. Hook your electrode holder to the positive side for DCEP.
Dave J.

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Simclardy
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What kind of rectifier are you using? I see some really cheap units <$50. I doubt they produce a smooth dc line. It will need some sort of capacitors to help smooth it out. Im curious. Let us know how it works

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Most welders use a choke you add capacitors too.

Dave
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Add a choke (inductor) if you are converting a constant current machine like a stick welder, and avoid too much capacitance. Add capacitors if you are converting a constant voltage machine and do not add too much inductance. Inductors steady the current flow and capacitors steady the voltage.
Multimatic 255
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Yes a choke with lot of turns is for stick welders.

But a choke (aks Reactor) with few turns with give a smoother DC .

Some old books on MIG with take about adding turns (also choke) for smoother welding.

Today if look most CV welder they will some type of choke / Reactor.

Dave
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