Any one else with this Power Max 1000 issue

[jeeplogic83]

Just wondering if any one is having a issue with their PM 1000 randomly not starting a arc. I have had this issue ever since I bought the machine. I have replaced one of the E-boards in it and it helped a lot now it only does it about 1 x daily instead of 10-15 time per piece.
Here is what happens. I will be cutting out a piece just fine and the torch head will move up over to the new cut, drive down touch off and NOTHING the plasma cutter shows the red fault light on the front panel. If I try and do a restart from this point It does the exact same thing. I have to turn off then back on the plasma cutter and then it will do the rest of the piece no problem. this happens with new consumables and old consumables there is nothing that seems to make it better or worse. I have every thing grounded and very dry air. I guess its not a huge issue but it drives me nuts that it's so random.
Any input would be helpful.

[jimcolt]

Inside the Hypertherm torch is a spring loaded plunger....which supplies the negative cutting current to the electrode. With no air flowing...the electrode is pushed forward untill it contacts the nozzle (which is connected to the positive side of the plasma output power)....creating a dead short.

When the plasma start signal is applied (either the trigger on a hand torch is depressed...or a start signal from the cnc is sent) two things immediately occur: 1. The plasma DC voltage is activated...and there is a dead short betwen the nozzle and electrod in the torch, 2. The air flow solenoid opens, sending air flow/pressure to the torch. The DC gets to the torch first.....then, when the air arrives an internal pressure builds between the nozzle and electrode.....and this pressure pushes the electrode back away from the nozzle (overcoming the plunger spring pressure)....which breaks the short circuited DC power...creating a spark between the nozzle and the electrode. This spark ionizes the gas flow, which starts the plasma pilot arc.

Here is what can cause the torch to misfire:

1. Air pressure/flow inadequate. Set the plasma air pressure by turning the amperage knob fully counter clockwise...this activates the air solenoid, and air will flow at the torch. Adjust the regulator on the Powermax1000 until the correct pressure is indicated (70 psi...as recommended in the operator manual). Low pressure will not allow the electrode to properly pull away from the nozzle.
2. Overtightened retaining cap. The retaining cap on this torch design must be carefully "snugged". Overtigtening will distort the swirl ring....which will impede the electrode movement inside the torch. A worn or damaged swirl ring or retaining cap can do the same....try replacing these parts!
3.Aftermarket consumables......there are a few brands of knock-off consumables available on the market....often they are manufactured out of tolerance. Use genuine Hypertherm parts....you will save time and aggravation...and they may cost more, but last longer.
4. Dirty, moist air. If you have dirt, oil, or water in your air system....it will cause rapid consumable wear...which will cause early misfires. This can also build-up in the moving plunger inside the torch, impeding movement.
5. Air hose leaks, missing or leaking torch o-ring....thses issues will show adequate air pressure as mentioned in (1) above....but the air will bypass before getting to the torch, causing misfiring.

Last, but not least....worn out consumables. If the torch misfires after a fair amount of use....often you can remove the electrode and nozzle....clean the front of the electrode and the inside of the nozzle with scotchbrite...make them shiny and re-install in the torch. If you suspect a sticking plunger in the torch....you can download the service manual (www.hypertherm.com, download library, choose system type (Powermax1000), choose manuals, then service manual) and it will walk you through the torch assembly.

To breathe new life into a Powermax 1000, 1250 or 1650...upgrade to the new Duramax torch (you can find details on www.hypertherm.com). This new torch design provides better cut quality, speed and consumable parts life....as well as eliminating misfiring issues that can be caused by the above issues in the older torch design.


Hope this helps....Jim Colt Hypertherm

[SCHIDTHEAD]

I believe I may have run across something else for you to add to that Mr Colt. I have had that issue on occasion but only cutting thin guage. I believe the problem was in a bad touch off so I started using heavy wall 4x4's to keep my material on the slats which reduced my no starts to almost nill. However, I still cannot get my torch to run fine tip consumables--it mis-fires constantly no matter what I do.

[jeeplogic83]

Jim Thanks for the suggestions I will try that first before the upgraded torch. (Unless Hypertherm wants to donate one)