Samson 510 PlasmaCAM 3.11 Stops cutting and gives an alarm on loss of torch control

[OSHO]

So I'm helping a colleague to set up and learn a Samson 510 plasma table he bought second hand about a year ago. It has an 80amp Hypertherm plasma cutter, a manual cutter that is modified for machine use.
Last year I was over and did an initial configuration and test run and it was working fine.

He finally got around to setting it up in its permanent position and wanted me to help get it running again and give some basic training on how to use it.

Now when cutting the controller seems to loose the indication that the arc is lit and that the plasma is firing.
The one difference is that he got new consumables for the plasma cutter. The ones we used last year were the ones that came with the machine which was the fine cut version.
The new ones are the standard consumables and are longer than the fine-cut ones.

The initial problem I had was that the head kept crashing in to the material. And when I checked the arc voltage for the THC i noticed the voltage was way off compared to the settings. So my theory is that the new consumables cause a longer arc and thus changing the arc voltage which leads to the height calculation to be off.

I went into the advanced settings and changed the max and min arc voltage settings from 3-12v to 8-12v(12.1 is max that it can be set to). And now the cutting distance seems to be ok.
Meaning that when the table stop mid cut and I check the torch height it matches the set cutting height in the program quite good. So the calculation for the THC is at least in the ballpark.

There are only 4 wires going to the plasma cutter through the 6 pin din connector. It should be 2 for starting the torch and 2 for monitoring the arc voltage over some type of current shunt is my guess.

So how is the controller sensing that the arc is lit on the torch?
Does the arc voltage have to be in a specific range for it so sense that it is striking an arc?

EDIT:
I realised that I messed up when explaining what I turned off.
I did not turn off the THC. I turned off the option "Wait for ready signal before cutting" it might have been worded a bit differently.

So the THC should still be active and seems to work since it cuts fine with only this option turned off.
The only thing I think it should effect is the pierce time and that it wont kick up an alarm if the arc goes out.

But it should work, and it annoys me that I haven't figured it out yet.

Thanks in advance for any insight you might have.

[adbuch]

The controller monitors the arc voltage. When arc voltage is present, the program assumes the torch is firing. In Design Edge, there is a setting for minimum cutting signal (Volts). It is normally set to 3v, but I seem to recall situations where lowering it to 1.5V or so may help.

Min cutting signal.jpg

The Machine Control for 3.11 does not seem to have that capability.

3.11 machine control.JPG

Perhaps Robert Johnson will have more insight into how to address your problem.

David

[rdj357]

....

And when I checked the arc voltage for the THC i noticed the voltage was way off compared to the settings. So my theory is that the new consumables cause a longer arc and thus changing the arc voltage which leads to the height calculation to be off.

What do you mean by this? You checked the arc voltage where? The only place the arc voltage can be monitored is a pilot arc fire in Machine Diagnostics. You are correct that the arc voltage is different for standard consumables than Fine Cut but the change that has to be made is in the Arc Voltage Shift setting, not the min/max cutting signal settings.

I went into the advanced settings and changed the max and min arc voltage settings from 3-12v to 8-12v(12.1 is max that it can be set to). And now the cutting distance seems to be ok.
Meaning that when the table stop mid cut and I check the torch height it matches the set cutting height in the program quite good. So the calculation for the THC is at least in the ballpark.

For Hypertherm it is sometimes necessary to set the MIN cutting signal to 1.9v with MAX staying at 12v. By raising this setting to those you're probably fudging the height here rather than the proper spot, the arc voltage shift as previously mentioned.

There are only 4 wires going to the plasma cutter through the 6 pin din connector. It should be 2 for starting the torch and 2 for monitoring the arc voltage over some type of current shunt is my guess.

So how is the controller sensing that the arc is lit on the torch?
Does the arc voltage have to be in a specific range for it so sense that it is striking an arc?

Correct, one pair is a switch for the trigger, the other pair is for arc voltage. If using the original Plasmacam torch control cable for/with a hand cutting torch clamped in the table, there is a 21.1:1 voltage dividing circuit built in. That is why the voltage shown in diagnostics is ~6 volts. The actual torch arc voltage it is reflecting is around 125vdc.

That is how the controller senses the arc being lit - voltage is present when the arc is present.

The range should be the Min/Max setting which should be 1.9v MIN and 12v MAX if using a Hypertherm power source. (The default of 3 is usually fine so to anyone reading this later, no need fixing a problem you don't have if yours is working fine at 3v)

EDIT:
I realised that I messed up when explaining what I turned off.
I did not turn off the THC. I turned off the option "Wait for ready signal before cutting" it might have been worded a bit differently.

So the THC should still be active and seems to work since it cuts fine with only this option turned off.
The only thing I think it should effect is the pierce time and that it wont kick up an alarm if the arc goes out.

But it should work, and it annoys me that I haven't figured it out yet.

Thanks in advance for any insight you might have.

Turning off this option can cause problems, usually on the second and subsequent cuts because there is a slight delay in the arc firing (due to post-purge) so oftentimes the torch begins motion before the torch has actually been on for the duration of the pierce delay. You will notice cuts that have no lead-in or have begun further down the cut path meaning that when the cut comes back around, it is not complete.

The best way to set your arc voltage shift is to make sure all settings are correct for cut and pierce height, pierce delay (time to pierce path), and cut speed and then put a check in the "Auto calibrate Z shifts on next cut" box on the height control page. Then draw and cut a straight line at least 6-10" long.

See how it works and let us know! - Robert

[OSHO]

Min cutting signal.jpg

The Machine Control for 3.11 does not seem to have that capability.

3.11 machine control.JPG

Ok, it makes sense that it uses the presence of a voltage to determine if the arc is lit. If you go into settings->Height control->Advanced in the 3.11 software you can set the min max values. I thought these were only for calibrating the sensing distance, to shift the arc voltage. But they are probably for the arc sensing.

In the same Advanced panel there is a "Z-Offset" value, which I didn't really think about when I was there, that might be what I was looking for.

The best way to set your arc voltage shift is to make sure all settings are correct for cut and pierce height, pierce delay (time to pierce path), and cut speed and then put a check in the "Auto calibrate Z shifts on next cut" box on the height control page. Then draw and cut a straight line at least 6-10" long.

I will try this as soon as possible and report back.

Oscar

[adbuch]

Oscar - I use Design Edge, which is different than 3.11 - but I do the same thing for auto calibration. This is what my settings page for height control looks like.

ht 1.jpg

And this is what my machine control settings page looks like.

ht 2.jpg

I will be interested to see how you make out with your machine.

David

[1MORECUT]

David, when did you get a table with 3.11 software?

[adbuch]

David, when did you get a table with 3.11 software?

Oscar - I use Design Edge, which is different than 3.11 - but I do the same thing for auto calibration. This is what my settings page for height control looks like.

John - I don't have a table with 3.11 software. Perhaps you mis-read my post.

David

[1MORECUT]

So how did you post pictures of 3.11 software?

[adbuch]

So how did you post pictures of 3.11 software?

John - I have the screen shots on file saved from images posted by a 3.11 user several years ago. I don't remember now where I got them - maybe the Plasmacam Owner's Community forum. I'd have to go back and check my Windows 7 computer where I originally downloaded them. I keep them on file just for reference material. Thanks for asking.

David

[adbuch]

3.11.jpg

3.11 1.jpg

3.11 2.jpg

3.11 3.jpg

3.11 4.jpg

3.11 5.jpg

3.11 6.jpg

[adbuch]

So how did you post pictures of 3.11 software?

3.11.jpg

[1MORECUT]

It shows that you uploaded the pictures.

[adbuch]

It shows that you uploaded the pictures.

John - in the future - you need to be a little bit more thorough in your investigation before making "accusations" . If you had taken the time to look thru all the posted photos at the Plasmacam Owner's Community forum, you would have found that these images were originally posted by another member who did have 3.11 and was asking for help. I simply saved them for future reference. If that's against Plasmacam policy, then have them give me a call to discuss.

David

https://www.owners-community.com/viewtopic.php?t=51736

311 post.jpg

[1MORECUT]

I did. You are welcome.

3.11.JPG

[1MORECUT]

Your pictures show 8/27/2022 you are welcome .

[adbuch]

Your pictures show 8/27/2022 you are welcome .

These screen shots were originally posted by another member on 5/30/2020. Look at the photo below.
David

311 post.jpg

[adbuch]

I did. You are welcome.

311 post 1.jpg

No - you did not! If you had thoroughly searched thru the shared images you would have seen the I was simply re-posting images previously posted by another member.

David

[1MORECUT]

You are the one that show me where you download the pictures. I found where you download them.

[1MORECUT]

So how did you post pictures of 3.11 software?

3.11.jpg

[1MORECUT]

David have you ran 3.11 table or used the 3.11 software? I have 16yr's run 3.11

[adbuch]

David have you ran 3.11 table?

No.

David have you used the 3.11 software?

No

I have 16yr's run 3.11

I'm impressed that you have so much 3.11 experience! Perhaps consider participating in some of the discussions on this forum and help to answer some of the 3.xx users questions when they come up.

David

[1MORECUT]

I do not go on this that much. I think Robert can handle it . Have my hand full with plasma cam site and my 4x8 kit I making.

[adbuch]

I do not go on this that much. I think Robert can handle it . Have my hand full with plasma cam site and my 4x8 kit I making.

John - be sure to post your 4x8 kit in the classified section here (when you get it ready to sell) so we can see what you have come up with. I had someone call me a few weeks ago asking for help - he was expanding his table to 10x20 with ball screw drive for his carriage across the gantry and wanted to know about the customizable size software upgrade. He was also wanting to raise his gantry for cutting taller pieces. I told him about your rail riser and tall Z kit that you used to offer. I said he should reach out to you at the Plasmacam Owner's Community forum where I think you have posted your phone number in the past.

David