256 plasma problems

I did some searching but didn't find the answer to my problem.

settings: 45 amps, pressure set at about 75. The air compressor is rated for 12 scfm at 90. Torch is in the negative terminal. ground clamp was connected close to the cut and on clean metal.

Plasma was working well for about an hour. Then it stopped. I would get a little spark and nothing. I then switched the machine off and when I turned it back on it would work for about 30 seconds. Switched machine off and on again, and this time only the small spark.

After I switched out consumables it worked for about 30 seconds and then only a small spark. I tried starting the torch away from the metal, touching the metal and on the edge of the metal.

Switched consumables again and same pattern. The inside part has the swirl pattern.

Tig and Stick seem to be working fine.

All knobs are turned to the off position.

As I was going through consumables I checked some different settings and it seemed that if I really cranked up the amps it would last slightly longer. I am only cutting 14 gauge though.

Any ideas??????

how is the air flow out of the torch there should be post flow. having 75 psi going in you may have blockage before the pressure sensor. also how is the pilot arc wire, you could also have a flakey switch pull the torch apart and check the switch. I had a problem with the switch on mine hook up the foot pedal and try that in plasma it will only turn it on or off.

Do you have an air dryer? Not the water trap we provide. Consumable use is almost always due to water/moisture in the line. The water trap is not sufficient. It also wreaks havoc on the internal components of the torch. You do need the post flow turned up. Sometimes having the start amps turned up helps.