welder woes

[ian.stewart]

Been having probs with the mig welder recently, [SIP160] I thought it may have been the liner punctured, But welding yesterday, I saw a huge spark shoot out of the area where the lead goes into the welder body, So im guessing the main live has been arcing for a while and burnt thru the liner,
Back to the spares box in the corner, I had Found a Euro Torch in the welding bay at work, No use to them, they threw away the BOC welder that used that torch, I also salvaged the plug from the scrap welder, the intentions was to have a 4m torch lead on my little welder.
All worked out fairly well with little problems fitting this to my welder,
Ive upgraded to .8 wire as well as the .6 wire was having problems feeding itself along such a long torch wire, so it all now appears to work.
Under the bonnet welding up a disused hole I thought I could smell burning, looked up and the garage was full of white smoke, coming from nowhere near where the welder or cables ran, Turns out it was the lead light, which has a metal clamp, I assume I never had the earthing cable of the welder making good contact and the welder was using the light flex as a earth, .
Now this is where it gets a bit odd, with my earth lead still connected and untouched, I pull the trigger and NOT welding or touching the car, Just feeding wire, the light lead started smoking again, can anyone explain this, Is it possible the torch has an internal earthing problem, I dont know,
I am going to try another torch tomorrow and see what happens.

any suggestions,??????
Ian

[JSF55]

Keep a straight head and check everything methodicaly, do a continuity check on the lamp and see if it has an earth, try and track down what has burnt, if the wire feed cleanly, i would doubt that it was the fault, check the welder over and all the connections, double check the earth point and the clamp itself and check it on the machine too.... best of luck .... and remember to put ur wellies on !

[ian.stewart]

Ive just been up the garage, and tried the welder, Just to see if it works or is totally cattled, Piece of scrap, EARTH correctly fitted, and it WELDED to a satisfactory level , So I am assuming it was the welder not being earthed correctly caused the lead light to go into meltdown, especially as I dont normally have the light attached to the car, the reason I assume the wire was melting with only the trigger pulled was the route of least resistance rule came into force and the welder was possibly using the lead light as an earth, including the secondary coils??

[winkle]

Never been good with electrics Ian but, does your lead light have an earth or is it double insulated? If im talking S***e just let me know

Steve

[Ian Anderson]

I have seen (at one of my last companies) that the electrition who installed the wiring had linked the Neutral and Earth as tere was no Earth provided by Seeboard / supplier - I got to hear the full story as it was surging and crashing computers.

Now I would summise that your Earth system is along these lines and probably the earth / neutral on the welder not good so it was finding another way home via your lead light

Quite how you check it and fix it is beyond my accountants knowledge

IAn