Nitrogen causing low voltage, not cutting

mminford · Post by **mminford** » Sat Jun 27, 2020 3:08 pm

I have a Powermax 85 using a CandCNC system. I'm trying to cut 1/4" stainless with nitrogen as the gas and 45A tip.

I've ran nitrogen through this system before cutting stainless steel. I had no issues. I cut a bunch of carbon with air, no issues. I went to cut stainless again and I'm getting a low voltage reading which causes the DTHC to rapidly increase it's distance from the workpiece. I turned off the DTHC and ran the same program, and it will cut for about 1/2" then will not penetrate through the material. I am running the same program as before and I tried other programs as well.

I switched the gas to air and it will cut. The DTHC works with air too. So I though then my regulator could be bad. I changed the regulator and still same behavior. I changed everything in the nitrogen system up to the machine, still same issue. I even changed the bottle.

As I stated, I ran this system with nitrogen and I'm only having this problem cutting with nitrogen. Does anyone have a clue to what could cause this issue? Is there something in the plasma that could cause this?

Post by **adbuch** » Sun Jun 28, 2020 12:31 am

What condition are your consumables in? I would recommend installing brand new Hypertherm consumables and trying again. My understanding is that cutting with nitrogen may diminish the arc voltage. 45 amps is also right on the limit for 1/4" stainless. You could also try switching to 65A operation. I have included the Hypertherm recommended consumables and cut charts for both 45A and 65A below.
David

Post by **adbuch** » Sun Jun 28, 2020 12:43 am

Here are the recommended Hypertherm consumables for 45A and 65A.

Here are the Hypertherm cut charts for 45A and 65A.

: 45 amp shielded stainless steel.jpg (85.42 KiB) Viewed 269 times

: 65 amp shielded stainless steel.jpg (87.91 KiB) Viewed 269 times

mminford · Post by **mminford** » Mon Jun 29, 2020 12:37 pm

Consumables were all replaced. I did not change to 65A yet. 45A cut fine on 3/16 but now that is even giving a lower voltage reading. Again only using nitrogen. Changed to air and cuts fine

Post by **adbuch** » Mon Jun 29, 2020 6:10 pm

Maybe try 65A then and see what happens.
David

Nitrogen causing low voltage, not cutting

Nitrogen causing low voltage, not cutting

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Re: Nitrogen causing low voltage, not cutting

Re: Nitrogen causing low voltage, not cutting

Re: Nitrogen causing low voltage, not cutting