Arc OK intermitent issues on torch fire

Hey guys i have an issue when starting a cut, the plasma goes to arc then immediately get "valid arc lost program paused" This seems to only happen around 40% of the time from what i have been seeing and i am at a loss for what could be causing this. I have a short video of what happens. video link >

Then the less common issue is the plasma goes to start an arc, It blows through the metal no issue but its like its not detecting its cut through and blown the metal away then proceeds to try a second arc start still not working then it pauses because its already tried to establish the arc the required amount of times. video link >

The picture has both the faults.

I am running a 7i76/6i25 THCAD10, latest version of plasmaC

Any advice would be amazing.

A few questions:

1. What brand plasma (looks like a hypertherm)
2. What mode are you using?
3. Actually can you just post a backup of your config? Click backup on the config tab, it'll drop it into your home folder and you can post it here in the forum.
4. For torch-on do you use a mechanical relay of a solid state one?
5. Have you debounced your arc-ok input?

One of the most helpful things will be number 3.

> Machine is jasic unimig razorcut45
> Using Mode 1
> not sure on the relay
> and i have not touched debounce settings as of yet

luftlupus wrote:

Attachment not found

> Machine is jasic unimig razorcut45
> Using Mode 1
> not sure on the relay
> and i have not touched debounce settings as of yet

The first thing I see that is odd to me is your torch-on pin.

You have:
I run the same setup (5i25 and 7i76), here is my torch on:
I'm fairly certain what you have is not correct. I believe spinena has to do with vfd's, spindles, etc.

Also, if I were you, I would debounce the arc-ok input assuming it is a mechanical relay from your plasma cutter. The following changes will give you 5 servo-thread counts of deounce (if your servo-thread period is 1mS, then a 5mS debounce). This may (or may not) save you some headaches later.

Edit your plas_connections.hal file and make the following changes:



Change: To:

Add:


Change: To:

snowgoer540 wrote:

luftlupus wrote:

Attachment not found

> Machine is jasic unimig razorcut45
> Using Mode 1
> not sure on the relay
> and i have not touched debounce settings as of yet

The first thing I see that is odd to me is your torch-on pin.

You have:

Code:

net plasmac:torch-on => hm2_5i25.0.7i76.0.0.spinena

I run the same setup (5i25 and 7i76), here is my torch on:

Code:

net plasmac:torch-on => hm2_5i25.0.7i76.0.0.output-00

I'm fairly certain what you have is not correct. I believe spinena has to do with vfd's, spindles, etc.

i was told by PCW to wire it that way on the spinena and someothers do it on different pins also.
ill also check into those settings cheers

luftlupus wrote: i was told by PCW to wire it that way on the spinena and someothers do it on different pins also.
ill also check into those settings cheers

Ok, so looking at the MESA manual for the 7i76, it looks to me like he told you to do that because the SPINENAs are spindle isolated outputs for controlling spindle direction... but they are special because they are opto isolated outputs coupled with darlington transistors, capable of switching a 50mA load of 0 to 100VDC.

I definitely had a problem with my plasma cutter doing almost the exact same thing I saw in your first video when I had it wired with a Solid State switching device.

I HAD to go to a mechanical, dry contact relay for the torch-on output for it to work. I would be willing to bet you're having the same problem. My guess is that it wasn't near enough current to bias the transistor, and therefore never completely closed the circuit to get a solid start. My pilot arc would be puny sometimes, and sometimes there would be none, sometimes it worked fine. I would get arc-ok lost errors, basically everything you've described.

Switch to a dry contact relay, and use a regular output. I would posit that the problem goes away.

snowgoer540 wrote:

luftlupus wrote: i was told by PCW to wire it that way on the spinena and someothers do it on different pins also.
ill also check into those settings cheers

Ok, so looking at the MESA manual for the 7i76, it looks to me like he told you to do that because the SPINENAs are spindle isolated outputs for controlling spindle direction... but they are special because they are opto isolated outputs coupled with darlington transistors, capable of switching a 50mA load of 0 to 100VDC.

I definitely had a problem with my plasma cutter doing almost the exact same thing I saw in your first video when I had it wired with a Solid State switching device.

I HAD to go to a mechanical, dry contact relay for the torch-on output for it to work. I would be willing to bet you're having the same problem. My guess is that it wasn't near enough current to bias the transistor, and therefore never completely closed the circuit to get a solid start. My pilot arc would be puny sometimes, and sometimes there would be none, sometimes it worked fine. I would get arc-ok lost errors, basically everything you've described.

Switch to a dry contact relay, and use a regular output. I would posit that the problem goes away.

Sorry you mean the internal plasma cutter relay? otherwise i am not using any relays

Also got word back that its a dry contact.

Using the spindle relay is OK on a 7i76. Thats how PCW suggested and it saves an output but I must confess, I never rewired mine from the output I started with after I read his advice.