Resurrecting a ESAB Handy Plasma 125

[Jose L Cuevas Garcia]

Hi, I know nothing about plasma cutters except for what I google around and I always wanted to get me a plasma cutter just for my hobbies.

Recently I got my hands on a ESAB Handy Plasma 125 (circa 2007), docs here.

I had a hard time trying to get consumables, it has a PT-34 torch, my local store gave me a heat shield and baffle for a PT-31/31XL torch (which I google and seems to be the same part), but then they got me an electrode and nozzle in a zip-lock bag with no labels, so not sure what part number of brand are they.

I was hoping for some troubleshooting tips to se if its worth trying to get this machine running (I will use it every other full moon for small/simple cuts).

My start attempt:

1. Assemble torch (electrode, baffle, nozzle and shield. (not sure how tight must be the shield, just gave it a hand firm last twist).

2. Secure the clamp to the test piece, no ground (do I have to ground the piece?)

3. The machine turns on, fan, lights, compressor turns on briefly.

4. I rest torch tip about the 15 angle and press the torch switch and nothing, NO air or HF, no arc (not sure what the HF would sound, but I imaging a transformer humming).

My Troubleshooting so far:

1. Voltage on bridge rectifier ok!
2. Voltages on board ok!
3. Did visual inspection of board, dont see anything that screams burnt-out!
3. Took out compressor and test it it runs fine, pressure switch seems in order too.
4. Measured torch switch and is OK!

Anyhow I would appreciate any pointers...

God bless you all...

[ccawgc]

This plasma has a hf only pilot. shows as only a very small blue arc. not visible in bright light.
the work clamp must be connected to a clean rust and paint clean spot. The torch will need a clean spot to fire and start cutting on.
will not start cutting through rust and paint. Once cut arc is going it will cut though paint and rust.
Retaining cap should be snug tight. inside the case you should find a spark gap which is the HF generator. Only sparks with trigger pull.
If this is sparking and the torch will now cut, check Resister R1 and R2 if one of them is open, torch will not fire. HF will spark off the side of the nozzle.