Valid Arc Lost 2

More
10 Sep 2020 05:16 #181553 by little_sparky
Replied by little_sparky on topic Valid Arc Lost 2
Had a busy morning and finally got around to jaycar.

Turns out they dont have 5W resistors in ceramic, only wire bound, will this do?

I grabbed 270 Ohm 1W ceramic resistors as well just in case but unsure if these will suffice.

Will the 3x 270 Ohm 5W wire bound resistors be fine? I assume they do the exact same job as ceramic resistors, just in a bigger footprint.

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 08:04 #181576 by tommylight
Replied by tommylight on topic Valid Arc Lost 2
They will do just fine.

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 10:09 #181600 by rodw
Replied by rodw on topic Valid Arc Lost 2

Will the 3x 270 Ohm 5W wire bound resistors be fine? I assume they do the exact same job as ceramic resistors, just in a bigger footprint.


Yes use these ones to handle the current.

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 13:15 #181626 by little_sparky
Replied by little_sparky on topic Valid Arc Lost 2
Phew, finally at 11:13 at night I have time to upload the ini and hal files, sorry it took ages.

I still havnt had time to wire in the new resistors to test if they work but here are the files to check them out.

My only concern is any debounce or lowpass filters I have missed.

Thanks for the help thus far.

hal

File Attachment:

File Name: jonty_plasma2.hal.txt
File Size:12 KB


ini

File Attachment:

File Name: jonty_plasma2.ini.txt
File Size:10 KB


connections.hal

File Attachment:

File Name: jonty_plas....hal.txt
File Size:2 KB
Attachments:

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 15:57 #181650 by snowgoer540
Replied by snowgoer540 on topic Valid Arc Lost 2

Phew, finally at 11:13 at night I have time to upload the ini and hal files, sorry it took ages.

I still havnt had time to wire in the new resistors to test if they work but here are the files to check them out.

My only concern is any debounce or lowpass filters I have missed.

Thanks for the help thus far.


I don't run a lowpass filter on the THC, so I can't comment there.

I (and a few others) run a debounce on the arc-ok input as it's a mechanical contact. It solved a problem similar to yours on my and CBEAR's tables. I attached a modified version of your connections_hal file to add a 5ms debounce to the arc-ok input. That could essentially equate to a 0.005s added pierce delay (which I doubt anyone will notice :)).

Between that, and pulling the minimum current through your relay contacts, you should have a reliable table for years to come.

Let me know if you have any questions.

File Attachment:

File Name: jonty_plas....hal.txt
File Size:2 KB
Attachments:

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 19:34 #181671 by rodw
Replied by rodw on topic Valid Arc Lost 2

[I attached a modified version of your connections_hal file to add a 5ms debounce to the arc-ok input. That could essentially equate to a 0.005s added pierce delay (which I doubt anyone will notice :)).

Between that, and pulling the minimum current through your relay contacts, you should have a reliable table for years to come.


Its never wise to do two things at once because you don't know what the fault was. Save this one until after you have wired in your resistors and cycled through a few attempted cuts. I personally think if it was a debouncing issue, you would have had problems well before this.

Please Log in or Create an account to join the conversation.

More
10 Sep 2020 20:11 #181676 by PCW
Replied by PCW on topic Valid Arc Lost 2
I would tend to disagree, debouncing should always be used with mechanical contacts
unless the sampling interval is slower than the longest bounce times.
The following user(s) said Thank You: phillc54, snowgoer540

Please Log in or Create an account to join the conversation.

More
12 Sep 2020 07:35 #181835 by little_sparky
Replied by little_sparky on topic Valid Arc Lost 2
quick update, wiring in the 3x 5W 270Ohm resistors didnt make any difference, also checked my PSI into the machine and had more than enough, turned it down to about 100.

Am putting in the new connections.hal code snowgoer wrote and will report back.
The following user(s) said Thank You: rodw

Please Log in or Create an account to join the conversation.

More
12 Sep 2020 07:45 #181839 by rodw
Replied by rodw on topic Valid Arc Lost 2
Did you cycle it a few times to burn off the oxidisation? Don't give up straight away...

Please Log in or Create an account to join the conversation.

More
12 Sep 2020 07:57 #181843 by little_sparky
Replied by little_sparky on topic Valid Arc Lost 2
Okay so, I think it works!

Cycled the machine through about 10 times, didn’t work.

Put snowgoers file in, didn’t work.

Went for a little walk from one end of the shop to the other wondering what the scrap metal price of a plasma cutter that I have been building for 2 years is worth.

Came back and had a thought, what if somehow the -24V isn’t supposed to come from field power on the board. So I moved it to the -24V from the DC power supply and it worked!

Makes me wonder, would it have worked without the resistors or the new code? I’m not sure but I will do a process of elimination to find out in the near future, for the minute I have some cutting to do!

Thanks heaps guys.

Please Log in or Create an account to join the conversation.

Moderators: snowgoer540
Time to create page: 0.187 seconds
Powered by Kunena Forum