Spindle control with UC300ETH

[GS76]

I am investigating buying your UC300ETH motion control board and your software.

I wanted to understand how you spindle control can work, for example:

1. How is the speed (S) changed: is it outputted as a 0-10V? I am using the following small DC speed controller, which requires 0-5V for speed control. https://www.pololu.com/product/1394

2. How could I configure stopping and starting a small 48 W DC motor i.e. should M03 and M05 be handled via relays. Can the UC300ETH give the required signal to the relay(s).

Thanks.

[cncdrive]

1.) You could divide the voltage by 2. to get 0-5V from 0-10V. Depending on the analog input impedance of the DC motor controller electronics a 2 resistors voltage divider itself may be enough if the analog input impedance is high enough or if it is low then you could add a voltage follower OPAMP.
2.) The UC300ETH-5LPT outputs are standard TTL level outputs (74HC14, 5Volt 20mA sink/source). So, they can't drive power relays directly as those usually required 50-500mA of current depending on the size of the relay and it's coil. You can drive any of the UC300ETH-5LPT outputs with the M3 and M5 commands, you can set those up on the UCCNC spindle configuration page.
And you could use a logic level mosfet or a transistor to drive the relay. Or you could use a breakout board which has power Mosfets on the outputs, e.g.: http://cncdrive.com/UCBB.html

[GS76]

Thank you for the reply in this regard.

Very informative.