I tore into the lathe this weekend and found a strange set up for the spindle speed control and am not sure what it's for. There is a large resistor next to the speed control and it's hooked up to a relay and the spindle motor. I'm guessing it's there for some kind of soft start but I'm not sure how it works and what times the relay to kick out the resistor and let the motor go to full speed. Could it be the small capacitor that is hooked up to the relay, or perhaps something in the relay it's self?
The reason I need to know is the coil on relay takes 28 volts to run and it use to plug into the original control box. It looks like this was used to turn the spindle on and off and I don't see an easy way to hook it up to a new breakout board unless it's a 5 or 12 volt relay. So I need to figure out if there is a good way to use this relay as it sits or if I can easily replace it with a 12 volt one.
Thanks for the help!
Dale P.