On 15 November 2011 02:41, Chris Reynolds <c_reynolds2...@yahoo.com> wrote: > So I've been running my mini-mill with EMC2 now for almost 2 years, and I've > gotten to where I'm interested in having the spindle controlled by EMC2,
I am guessing you have a KBIC speed controller. As has been mentioned, these are controlled by an analogue voltage from a potentiometer. Unfortunately one end of the pot is tied to motor +V so is at 100 Volts or so relative to ground. You can find the drive manual online, it tells you how to control using an analgoue voltage. Luckily, there is a common component that can help with this, DC to DC convertors have a few kV isolation between input and output, so the input 12V can be referenced to a completely different 0V than the output, which means you can safely connect that side of the circuit to the potentiometer terminals. https://picasaweb.google.com/108164504656404380542/Gibbs#5495687787404348610 Is the circuit I used to control my Mini-Mill. I had two spindles and was short of IO, so the circuit there is a lot more complex than you need, you can skip the relays on the right and the top half, just keep PS2 (the DC/DC converter) U4, U9, U7, R3, R12, R13, C1, D2A and VR2. U9 and the surrounding components is a precision current source, and could probably all be replaced by a resistor. I over-thought that bit. -- atp The idea that there is no such thing as objective truth is, quite simply, wrong. ------------------------------------------------------------------------------ RSA(R) Conference 2012 Save $700 by Nov 18 Register now http://p.sf.net/sfu/rsa-sfdev2dev1 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users