Premier Plasma THC Troubleshooting

[AdkissonCK]

Hello all,

We run a Premier Plasma table with a Hypertherm 65A Machine. Recently we had one of the power supply boxes go out and wasnt giving power to the Y Axis and the Z axis anymore. So we replaced that and then we noticed the Z axis still wasn't responding or showing power so we replaced the sterpper drive for that as well. However now when we try to run a file the THC is acting up. For example, we are cutting 14 gauge and I always cut around 65 volts for this thickness, the thc is either diving down and dragging on the material around 40-45 volts or its doing the complete opposite and pulling way up to around 100 volts.

I did recalibrate the z axis after we switched everything, I have brand new consumables, I ended up replacing the probe switch too for good measure. I am out of ideas to try at this point.

My only other wonder is because when we replaced the stepper drive, it is slightly newer version then the rest, would it be causing it to act funny? All of the connections are the same so I don't see why it would. But we are at a loss on what else to try.

[acourtjester]

Do you think you had a power glitch and that is what blew out your power supplies? That may have affected the software, more than the Z axis info may be bad. You can copy one of the XML files in the backup folder for the older settings to get you back before the problem occured.

[AdkissonCK]

Oh I didn't think about trying that. Thanks for the suggestion, going to try that now.

[AdkissonCK]

Ok, I am back, I am still having the same issues. I have done a backup of the XML files for mach3, but nothing is helping. I have tried adjusting THC voltage both ways and it still is either diving way down and dragging on the material or raising way up and barely cutting through the surface of the material. There is no in between it is no longer maintaining .06" cut height.

If it makes it through the first test cut, when it moves to the second it will either stay resting on the material causing an error probe call, or it is way above the material and is reading (zero) to be well above the material and therefore not actually piercing or cutting the material again. it's like z axis is completely malfunctioned and cant find true zero.

[acourtjester]

Thanks for the reply, Well let's try a little different operation. I would generate a G-code using a post processor without the THC and leave the plasma off and run the G-code. Something else you can run a G-code called roadrunner it should be in the Mach 3 folder, this is a test G-code for motor action. move the table out away from the sides and put the Z about in the middle of its travel. Zero out the DROs and run it. It should move around and move the Z up and down about 1". If that works your THC may be bad too.

[AdkissonCK]

Excuse my lack of knowledge on this particular matter, but can you explain how to generate a G- Code without the THC.

[acourtjester]

Understand we all started in a similar place, Are you using a CAM software like SheetCam of Fusion 360 that you use for generating your G-code.
What you want to use is a post processor that does not add the lines of code for using a THC unit. Here is one ready to use, unzip it to find a .tap file copy it to your folder where you store your g-codes. When you are ready position the table in the middle X and Y set to 0.0 and place the Z axis in about the middle of its travel set it to 0.0 too. Load and run the RoadRunner G-code it should move the 3 axis around if they are work correctly.

roadrunner.zip

[AdkissonCK]

I appreciate your help so much, I will give that a try. I do run sheetcam so we shall see if I can get it figured out. At this point i just need to bypass the thc completely, we are looking at upgrading that whole system after this mess.

[AdkissonCK]

Okay, so from what I am observing it looks as though all x, y and z axis are moving as they should. the Z axis did move up and down per the roadrunner code.. so does that mean I should go ahead and replace my thc now? We run Proma SD; I definitely think there are better options out there if that is the case here.

[acourtjester]

The Proma SD is one many have had problems with, there is one I looked at but know nothing about it. It was on eBay and is from Europe so the shipping may take some time. https://www.ebay.com/itm/134073671191 I like the Price unit but not sure if they are still on the market.

[weldguy]

I would expect the issue is with the thc. I have seen Z axis behave the exact way you have described so many times and it is typically a configuration issue or it is malfunctioning and needs to be replaced.