Hypertherm HPR130 no sustained arc

[Jaymon]

Hello all, I'm just starting out with plasma cutting and am working on getting my table up and running. I've never done any plasma cutting before, but do have experience with CNC's, mostly router tables. I'm learning and figuring this out as I go. I'm having issues that I hope you experts can give me advice on.

I've purchased a used Vicon 5'x20' table that came with a HPR130 w/ Autogas plasma and a Hypertherm Command THC.

I have the table working well, but I'm struggling to get a sustained arc for cutting from the plasma generator. There is an initial pilot arc that will blow a hole in the plate, then a much smaller arc happens between the torch and the plate several times and stops. I get a "NO PILOT ARC" error code 20 from the plasma controller. Here is a Videoof what it does before the error.

I'm testing on a piece of 1/2" MS I had laying around. The torch is brand new from Hypertherm, consumables are new and set up for 130A cutting on mild steel with O2/Air.

I started off with the troubleshooting guide for this error in the HPR130 Autogas manual with the following results:

1. Verify that the consumable parts are in good condition. - Brand new, never used before these tests
2. Verify proper preflow and cut-flow settings. - Set from the cut charts in the autogas manual
3. Perform gas leak tests (see Maintenance section). Fails the inlet leak test, passes all others. I've read through the inlet leak test and don't see how this would cause the failure I'm having
4. Verify spark across spark gap. Called Hypertherm about this one and had them show me what to look for. Checked and verified there is a spark across the spark gap in the ignition console.
5. Inspect CON1 and pilot arc relay for excessive wear. Both appear to be in good condition
6. Perform gas flow test (see Maintenance section). Flow tests perform to the set pressures
7. Perform torch lead test (see Maintenance section). I get 0.3 ohms between the nozzle and the plate
8. Perform start circuit test (see Maintenance section). I get 14.6 kohms between H8 and C1 instead of the 15 kohms it says it should be. I get 5.4 kohms instead of the 5.5 kohms it should be. 1ohm across R1, as it should be.
9. Perform chopper test (see Maintenance section). Maintenance says it should throw certain errors on startup if the chopper fails tests, no errors.

The shop air is filtered and dried with a refrigeration air dryer, all brand new installation with new airlines.

I can fire the torch manually well above the plate and it gives a steady blue/white arc no flickering or sputtering. It is larger than I expected from reading some troubleshooting guides on Hypertherm's site. It says it should be 1/4 to 1/2" long, its more like 1" long. Maybe because I'm using the 130A settings?

It seems like I'm getting to the point that it should be detecting the pilot arc through the worklead, but for whatever reason it isn't detecting that current and therefore doesn't transfer the pilot arc to the cutting arc. When I watch the gas pressures during the attempts to cut, it never makes it to the cutflow stage. I've verified there is low resistance (0.3ohm) between the plate and the slats, slats and table, table and ground bus. There is a work lead between the ground bus on the table and the plasma generator.

I don't know how to verify the current sensors on the worklead are working. When I check impedance through coils CS1 and CS2 where plug into the power control board, it get the same value for each one. Don't know if that proves anything one way or another.

That's where I'm at and not sure what to try or check next. I'm reluctant to start replacing boards without some kind of verification that it is actually the problem.

Any advice would be greatly appreciated and thanks for your time.

-Jaymon

[weldguy]

I don;t know much about your setup but have you checked to see if you are getting an Ok to move signal from the plasma cutter to the controller?

[Jaymon]

I took a video of the power supply board with all the I/O LED's and laid out all the changes in a spreadsheet.

It appears as though the 'machine motion' output comes on just after the pilot arc.

[Jaymon]

Figured it out. I had 211VAC and needed 240VAC. installed a transformer and all the problems went away.

[adbuch]

Figured it out. I had 211VAC and needed 240VAC. installed a transformer and all the problems went away.

Glad to hear you figured it out. I had to put something called a "buck/boost" transformer onto my magnetic bending brake go get the 240 Vac down to the required input voltage. As I recall it was somewhere around 228 Vac.
David

[weldguy]

Glad you figured it out and thanks for posting back with your results. Nice find