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AMB PWM Spindle

Posted: Sun Mar 29, 2020 4:06 am
by BiuTse
Hi,
I tried to control rpm on my spindle but it seems that it is not working like it should.
I used your settings from the PWM Spindle guide but with a max rpm of 25'000 and min 5000 (according to spindle specs)

Now using M4 S25000 gives an rpm of about 10'000 (not 25'000) and M4 S5000 --> 4990rpm

any idea what to change?
by
BiuTse

Re: AMB PWM Spindle

Posted: Sun Mar 29, 2020 9:43 am
by Doug
Can you post pictures of your spindle and spindle controller, and a screenshot of your spindle configuration on the BB Controller? This would help me get started making some coherent suggestions.

Doug

Re: AMB PWM Spindle

Posted: Sun Mar 29, 2020 1:03 pm
by BiuTse
Hi,
Picture of spindle won t help much. Because integrated controller.

https://www.sorotec.de/shop/Spindle-Mot ... -7142.html

Configuration screenshot I will post tomorrow.

Re: AMB PWM Spindle

Posted: Sun Mar 29, 2020 4:19 pm
by Doug
The referenced link says that the speed control is achieved through a 0-10Volt analog input. Are you connecting this directly to the 0-3.3 Volt PWM output on the Buildbotics Controller, or do you have an adapter that converts the 3.3VPWM to a 0-10V analog output?

Re: AMB PWM Spindle

Posted: Sun Mar 29, 2020 10:08 pm
by BiuTse
I think there is the problem! Thx

I have connected it directly to the output. Which won t work if only 3.3V. I didn t look enough into the spec.

Now the question is what kind of circuit do I have to buy to convert it. Best would be a ready to go solution

Any idea?

Re: AMB PWM Spindle

Posted: Mon Mar 30, 2020 6:46 am
by BiuTse
So tried with my Lab Power supply and it works. So now I have to find a ready to use solution to get this buildbotics output converted.

Re: AMB PWM Spindle

Posted: Mon Mar 30, 2020 12:37 pm
by Doug
You should try a module like this:

https://www.ebay.com/itm/3-3V-PWM-100HZ ... SwJ8hcig-o

You will most likely find that it allows nearly the full speed range, but is not particularly accurate. If you try it, I'd really like to hear how it comes out.

Re: AMB PWM Spindle

Posted: Mon Mar 30, 2020 9:53 pm
by BiuTse
Yeah also saw this. Ordered one to test. Comes from CN so have to wait. (Couldn t find anything like this outside cn)

But till then I will use my power supply to control speed.

I will give you feedback!
Thx for the help

Re: AMB PWM Spindle

Posted: Mon Mar 30, 2020 10:00 pm
by BiuTse
And if quality isn t well enough I will try to built one by myself. Milling/graving the pcb with the cnc.
But first will try the cn product

Re: AMB PWM Spindle

Posted: Tue Mar 31, 2020 8:44 pm
by Doug
Would you be willing to share the design if you choose to design it?