500W Spindle Control using DS3502 Digital Pot

Community
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I have an old spindle and controller that I was wondering if I could make controlled by Arduino (Etc). My controller is NOT the Mach 3 version, so no extra port. (I had bought a “PWM to Voltage Converter Module 0-100% to 0-10V” module for that, but then realised I didn’t have the Mach 3 port.

Anyway, has anyone tried using a DS3502 Digital Potentiometer for this or has the experience to give me confidence to blow things up… ヽ(°〇°)ﾉ

https://www.aliexpress.com/item/1005006415152981.html

https://www.aliexpress.com/item/32921141477.html

P.S. I saw a video a few weeks back that said something about cutting a trace on the module so that it will use the PSU voltage instead…???

EDIT: Found the video…

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Would you care to show a few pictures of what you have?

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Not much really yet…

I plan to test using an Arduino Nano, link it to the DS3502 and then the power controller (both linked above)

I realised (finally looked) and the existing pot is actually a 4K7, and there was 1.8V across the pot terminals.

I don’t really know what I’m doing so I dwell a fair bit, just not finding many example circuits and the ones I found sort of just feed back into the original device to check the output.

Cheers

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Just starting a little tutorial site, so will eventually draw it up…

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I’m missing something here.

A potentiometer is a variable voltage reference source.

A PWM to voltage converter is a variable voltage reference source.

I don’t know what voltage your controller puts across the potentiometer, but you can measure that.

If it’s 10V, I’d think you should be able to just use the PWM to voltage converter module from the 0V side to the wiper port on the “potentiometer” connection for your spindle controller.

If it’s less, you should be able to create a voltage divider to make the PWM to voltage converter be in the range that the controller expects.

I’m with @dougl — pictures of what you do have will make us more likely to understand.

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OK, later, I’ll sort a few pics and do a sort of circuit diagram… Thanks

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I’m really looking to see what your original controller setup looks like. I’ve got an old 3040T CNC and somewhere I have links to how to control the circuitry for the spindle, just a 400W air cooled one. Repeat, not looking to see pics of what you want to put together, just what your controller and spindle POT setup looks like.

dug through my notes on the old 3040T and found the spindle control hack and display add-on hack. 3040 CNC Milling Machine Mods | Hackaday.io

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lol, mine is totally homemade, it is a nano, a 12V 10A PSU, 3x TB6600 (Nema 23) and the 100V controller shown above for the 500W spindle, oh and an emergency stop!

The website I’m doing is also for releasing my CNC plans, made out of box section 20x40 and 50x100, oh and SBR12 rails… I’ll post some links for that by turn of the weekend… My bearings came today so may have to put my little Scara arm together tonight!!! (Thingiverse - Scara robotic arm by Idegraaf)

(˶˃ ᵕ ˂˶)

P.S.

Reading your link, I started writing a GCode sender a few weeks back (to control a uStepper arm), I too had issues with G54, can’t remember but had to force it into a mode to report WPos. I’ll be making time for another few sessions over next week or two, so I’ll read my notes and see what I can say.

I got distracted with life over last few years, so only just getting back into this lark, but I did buy some optoisolators for trying to control the spindle but never got brave enough to try. I’ve half made a lathe and was wanting to try use the controller for that… replace the bulky 0.75KW 3 phase…

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