Spindle control via PWM, Linux CNC on DC motor

[Jools]

Hi All

I'm improving my mill and am looking to add spindle speed control from LinuxCNC to my Sieg X2 mill. I don't really want to change the spindle to AC and go the VFD route so am looking to use the PWM output to control everything. So was wondering if anyone had done this and how they had done it? I've found links to the Mesa spindle controller ( http://store.mesanet.com/index.php?route=product/product&product_id=205 ) and wondered if this then plugs into my mills transformer in some way to replace the manual variable resistor that controls speed. If it does has anyone got wiring plans or photos?

If there are better ways to do this then please let me know too.

Specs on the motor are in the attached photo.25193

Jools

[magicniner]

From your link -

"The SPINx1 is a one channel isolated digital potentiometer intended for spindle control. The SPINx1 takes three TTL level signals, PWM, DIR and ENA and has four isolated outputs: CW, CCW, ENA and VOUT. VOUT is a Analog voltage proportional to the PWM input signal and the Analog reference voltage (5 to 18VDC)."

You can easily find out by wiring an external potentiometer with it's own PSU and patching that intou your existing system, if that works then the linked unit should work.

[Jools]

Thanks for that.

Further investigation shows that the Leadshine MX3660 that I have has an analogue 0-10v out for spindle control. I've opened the potentiometer on my Sieg mill and the voltage there seems to be 4.7v max so could I just remove or bypass that potentiometer and use the outputs from my MX3660 if I calibrate them correctly?

[Clive S]

Thanks for that.

Further investigation shows that the Leadshine MX3660 that I have has an analogue 0-10v out for spindle control. I've opened the potentiometer on my Sieg mill and the voltage there seems to be 4.7v max so could I just remove or bypass that potentiometer and use the outputs from my MX3660 if I calibrate them correctly?

NO. As you will need an isolated pot, -- https://www.ebay.co.uk/itm/1-3KHZ-to-0-10V-PWM-Signal-to-Voltage-Converter-Digital-Analog-PLC-New/162883914343?hash=item25eca34a67:g:yFsAAOSwx4Zak5z L:rk:1:pf:0

with an isolated small power supply https://www.ebay.co.uk/itm/AC-DC-Converter-Switching-Power-Module-AC-110V-220V-230V-To-DC-5V-9V-12V-15V-24V/263040639593?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649


and configure Lcnc to give you a pwm signal.

Unless the MX3660 pot is already isolated.

[Jools]

NO. As you will need an isolated pot, -- https://www.ebay.co.uk/itm/1-3KHZ-to-0-10V-PWM-Signal-to-Voltage-Converter-Digital-Analog-PLC-New/162883914343?hash=item25eca34a67:g:yFsAAOSwx4Zak5z L:rk:1:pf:0

with an isolated small power supply https://www.ebay.co.uk/itm/AC-DC-Converter-Switching-Power-Module-AC-110V-220V-230V-To-DC-5V-9V-12V-15V-24V/263040639593?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649


and configure Lcnc to give you a pwm signal.

Unless the MX3660 pot is already isolated.

14.3. Connecting the Analog Output
The analog output connection is optional. The MX3660 3-axis stepper drive also comes with an opto-isolated
analog output (Figure 3) to allow control of an external analog device, such as a VFD for spindle control. Supply
voltage for the analog device is 5-15 VDC, and the output voltage signal is 0 to (Analog Supply Voltage minus 1.1
VDC).

It looks like it already is.

So is it just a case of configuring LinuxCNC to give me the PWM signal as per the documentation?