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AC arc welder transformer connection

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AC arc welder transformer.

I tested the transformer as follows:
-All wires are separated from the switch and from each other
-There are 9 red wires, 6 gray and 2 thick uninsulated copper leads to which the main cables for the electrode holder and ground are connected.
-No wire has contact with ground.
-All red wires have mutual continuity
-All gray wires have mutual continuity
-Two thick uninsulated copper lines have mutual continuity
-There is no mutual continuity between wires of different colors, nor between any colored wires with thick uninsulated copper conductors.
- The resistance was tested and recorded in the table below, using a multimeter with a measuring range of 200 ohms.

  • The red wires were numbered at the bottom with numbers 1 to 7, two were not numbered and I marked them with 8-9A and 8-9B.
  • The gray wires were not numbered and I marked them with numbers 91 to 96.

Does anyone have an idea how this transformer works or a test method that might be useful in getting the machine up and running?


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All those conductors provide different power and voltage settings and it would be highly optimistic someone from afar can tell you where it all connects.
I have a 13v AC transformer, to which wire numbers should I connect it to without destroying the windings.

This was an old arc welder with a switch input voltage of 220V - 0 - 380V
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