Torch not firing

[RAD]

Hi, have anyone had problems with the torch not firing? I have a powermax 800 with duramax torch, recently the torch would be cutting and when moving to the next cut the torch would not fire, the problem was occasional but now its permanent. Air flows through the torch when the trigger is pressed but no plasma arc. I have checked the air pressure on the unit and it is set correct, i have replaced the swirl ring, cleaned the electrode with a scotchbrite pad, changed the nozzle but same problem. Wether using finecut or 45amp consumables same thing.

Any ideas what could be wrong? The only two things that was not replaced was the electrode and retaining cap (they both look good, since 3 months of cutting i am on my 3rd electrode and same retaining cap). The plasma unit powers up fine and sounds normal. I am out of ideas what could be wrong, any help would be appreciated thanks

[Old Iron]

On the front of the machine are both top green lights on?

[RAD]

Yes both green are on

[sawdust1]

I do not know anything about your particular machine. I would try, even temporarily new electrode and nozzle.

My first thought was the air as well but sounds like you have that covered. My lines were too long and the pressure dropped just enough to prevent firing, by the time I got my head down there to look at the guage the pressure had come back up and it looked good. Of course the torch can not fire half way through a cut. I sat on the floor ignored the topside and just watched the face of my machine.
David

[RAD]

Thanks. Just tried a new retaining cap but did not help. I also noticed alot of air coming from the top of the retaining cap when I press the trigger, is this normal?

[jimcolt]

It is normal for some air to exit the top of the cap. I trust you have contacted technical service.....in case you have not: technical.service@hypertherm.com or 1 800 643 9878 . Jim Colt

[RAD]

Thanks Jim. Yes I have contacted them and we are currently trouble shooting to find the problem; they asked me to do a resistance test to see if the electrode is separating fron the nozzle, and they seem to be separating as they should but still no torch fire.

So far I have changed all consumables including the swirl ring and retaining cap so I think that rules out the torch unless it the torch head.