Welding Machine Cables

I don't know what length you're referring to but make sure to use the right cross-section work cables, keep them as short as possible, never coil them up, and extend the hand piece cable if possible only as much as necessary.

Using longer power cable is a better and cheaper option than using long welding cables to prevent inefficiency, as well as to keep the costs down due to the thick copper cable can be expensive.

It also limits the voltage at the arc due to the resistance of the cable.

We recently had some NCRs during audit due to the cable length.

→ British Standard 7671.

PWSlack:

If you have took a look at it. You may give me which page to refer to.

Regards,

You can use the Adiabatic equation to calculate the thermal stress on the cable.

Hello, I try to make the power cable to the welder as long as possible to save on cost and work by rolling out the heavy leads. I don't remember the exact size number on the leads I buy but they I buy the lead at least one size bigger than required to compensate somewhat for voltage drop. I usually run the electrode lead in 50' increments to where I am welding at. I use a smaller 12 foot stinger or short section of lead with a 150 amp electrode holder with a quick disconnect for pipe welding because it is much easier to control than the big ole honking 200-250 amp holders I would use for heavy structural steel. Most of the time it is possible to run far less ground lead by grounding to the structure closer to the welding machine and let it carry the current to ground.

This works very well as long as the welder is familiar with the item he is welding on and there are no bearings, sensitive instrumentation or mating surfaces with close tolerances between the welder and the ground clamp that if current passes through would be ruined by arcing from the bearing surface to the race.

I got a very good paying job once that consisted of welding 4, 2" pipe couplings to accommodate cables for a painters scaffolding in the top of 8, 300 foot tall steel silos that hold plastic pellets. Because there was no moving parts or bearings between the welder and the silo roof I was able to safely use the silo shell as a ground cable. byBy doing this I only had to lift 300 ' instead of 600" cable to the roof after I climbed a dad burn ladder up the side of those silos which made the job a good bit less sweet. After I got finished with 1st silo I hired a helper to go up and pull the leed and although that helped I still had to climb that 300' ladder.

One the other hand I have seen where one welder that was not thinking did a huge amount of damage to a paper machine because he was to lazy or to stupid to run a separate ground lead and attach the ground close the point of welding. In the dryer section alone he ruined 60+, 6" roller bearings and journals and several rotating steam joints when he welded a tubing support to the structure that was worth less than 50 bucks. He also would have bankrupted the contractor he was working for if it wasn't for most of the damage was found over the next year as the bearings would fail.

Very good points!!!

I was a little lazy myself to spell them all out hoping that our friend would know all these issues.

If you get at least a 50 square mm cable or greater than it is OK. We used to use 70 sq mm welding cable for welding upto 6.3mm electrodes all day long. It would get warm after a while but I doubt it if you'd be burning 6.3mm rods all day, would you? Make sure the cable connections on the ends are always tight!!! Else heat will build up.