Plasmacam DH2 - Error Message

[JKSafetyPro]

I am running a Plasmacam DHC2 machine, and up until tonight, have not had a lot of issues with the machine. I had to recently replace the torch cable, and had a few minor issues. This evening I was cutting 14 gauge, when the problem started. Click on Cut and the machine won't fire, you get the error message "Torch cutting not detected". Click OK, and then Cut, it may or may not fire. This process can go on up to 20 times. Then it'll fire and make one pierce and we can start the process over. The most it has fired in a row, is 3 pierces. I have tried everything that I can think of doing, I am at a loss. I have orders that I need to get cut and can't get my machine fire and stay running. Any help would be greatly appreciated.

Jeff Krohn

[admin]

Sounds to me like a problem with your plasma cutter rather than your Plamsacam. Check the air pressure when the air is flowing and confirm it is correct. Be sure your ground clamp is installed. Make sure that your torch tip is not in contact with the material when you peirce the plate and that stand off distance is proper. Check to make sure your consumables are seated properly and in good condition. If your torch has a start cartridge confirm it is in good functioning condition. Will it fire every time if you trigger it with a remote trigger or hand torch trigger? Check these things and post your results.

Admin

[Ironman]

You haven't said what cutter you are using, but 2 things will cause that. Icing in your air line is one, or a plugged water filter. The result is restricted flow and cutting will stop.
The other is (and this is Hypertherm specific) that the moving parts in your torch head become stuck. I would replace all parts, swirl ring, electrode and tip, and see if your problem disappears. Try using the "test" button to fire the torch, and if that works, sometimes the simple cure is to rap the torch head a couple of times with a paint brush handle or the back of a screwdriver handle. Sometimes a miniscule piece of something (dust) will get in the swirl ring, and the electrode will not move.

[JKSafetyPro]

It's working fine now. Thanks for the input, I was positive the problem was software related, but I went thru the machine and figured out what happened and corrected it. The cutter is a Hyoptherm 900 which I purchased in 2000. The plasmacam I got in 2003, and started to use regularly in 2005. ( Really long learning curve on this end.) Yesterday I was cutting 14ga which my supplier got from a different vendor. The steel was oilcanning; every time the torch made contact, then the steel followed the torch tip back up. When the computer would give the signal to pierce the metal was very close, if not touching the tip. and I managed to weld 8 tips to the metal. I tried magnets, clamps and even flipped the sheet over to eliminate the problem and finally set the sheet aside for use on something else. I had some orders to cut out of 12 guage and put that on the table, when the error message started giving me fits. Today I was looking at the ruined electrodes and noticed for the first time in 9 years that the tops were pitted. Inside the torch head there is a spring loaded spool which was also pitted. I had replaced the entire torch and cable in July when the 900 stopped cutting and gave me a blinking red light, which meant a wire was broken somewhere in the cable. The old torch had barely any pitting! I took the new torch apart and put the spool piece in the drill press, using a piece of flat stock and 800 grit paper and managed to sand down the spool and remove the pitting. Put it back together and it works fine. I did have water issues when I first got the 900. I put a water trap and a Motorgard-60 moisture filter on the compressor and haven't had any water show up in the water trap on the back of the 900. Thanks again for the advice, otherwise I would have had to wait til Monday to call tech support somewhere and maybe been waiting weeks to find out there was nothing wrong with the controller or the machine. Now if you have any suggestions on eliminating the oil can issue, I like to hear them.

Jeff

[fitzy]

the oil can be easily removed by wiping it down with a rag dipped in paint thinner or other solvent hope this helps

[admin]

If by "oil can" you mean it's bowed and warped then I often use a short peice of a broom handle to hold the material down near the pierce location until the torch pierces and the auto height control takes over to eliminate tip to material contact during the pierce. Once you have astablished an arc and the machine is cutting the auto height control should compensate for the warpage throughout the rest of the cutting process.

Another thing you can do if you are cutting smaller parts and don't require a full sheet you can shear the sheet down into smaller sheets which will often releive the "stress" in the sheet that's causing the warping. If you don't have a shear just cut the sheet down on your plasma table. Anyway, glad to hear we were able to help. Thanks to everyone who took the time to help this Pspider member.

Admin

[Ironman]

The DHC2 should have ohmic sensing which means it senses the air gap and reads distance befor the arc lights up.
The DHC only runs on arc voltage for height sensing.
you sound like you have a DHC not the DHC2 model?
I never knew what it was called-oilcanning-makes perfect sense. I hate loosing a tip like that.
If cutting multiples out of the sheet I hold it down by fingers and cut out in various spots on the sheet and it usually gives up the fight then.

[JKSafetyPro]

Thanks for the suggestions on the oilcanning issues. I should have thought of making the slices to relieve the "stress" in the sheet. I've run into that problem just a couple times and usually just cut through it. This particular sheet was unreal, even after I flipped it over. Cut 2 more sheets tonite without a single misfire. I'm going to have to check my machine but I'm positive it's a DHC2. I haven't heard of the ohmic sensing, it normally stalls on the material, raises about .250 of an inch and drops down to about .080 when cutting. The Z-axis is active and it maintains the cut height when the metal warps during the cut.

Jeff

[Ironman]

Jeff, the ohmic sensor of the DHC2 has a wire running to a clip on the torch nozzle shield so the torch lowers to make electrical contact with the surface. Then it sets height and stuff off that. If a bit of slag gets in the tip it stops and says "Torch contact with plate", and will not fire the torch or move til the problem is corrected.
If it touches a tip up, it does the same thing. It is basically impossible to burn a tip by "oilcanning" on the DHC2 unless this feature is shut off.
You will be using the ohmic deflector part no. 220404 and the 220061 Ohmic cap if you have DHC2

[harlan5791]

I agree that it is a cutter issue. My thermal dynamics 100amp machine did that and I had to monkey around with the tips,dryer,restart it etc. It's very agrivating.