Spindle control via PWM, Linux CNC on DC motor

[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...k5zL:rk:1:pf:0

with an isolated small power supply https://www.ebay.co.uk/itm/AC-DC-Con...72.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...k5zL:rk:1:pf:0

with an isolated small power supply https://www.ebay.co.uk/itm/AC-DC-Con...72.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?