Hi, You could always just purchase one of these. :)
http://homanndesigns.com/store/index.php?main_page=product_info&cPath=1&products_id=38 or http://homanndesigns.com/store/index.php?main_page=product_info&cPath=1&products_id=21 It does exactly what you are after. Cheers, Peter. On 23/06/2011 12:19 AM, andy pugh wrote: > On 22 June 2011 04:12, Edward Bernard<yankeelena2...@yahoo.com> wrote: > >> I have thought about replacing the potentiometer with an interface to >> EMC2 and would love to hear any ideas to accomplish this. My first thought >> was >> to use an Arduino board to accept a PWM signal and control a digital pot. >> Any >> better (simpler) ideas? > > I think this circuit ought to work > https://picasaweb.google.com/bodgesoc/Gibbs#5621046688941452194 > Which is something I have meant to try for a while. > I have a feeling I have drawn it before, and that time I was more > confident in it, I think I have left out some critical resistors. > > The idea is that it converts a 5V PWM to a completely isolated > voltage, which could be to a different reference, and of a different > magnitude. I imagine connecting it in place of the pot on a VFD for > example, or to the 100V floating pot terminals on a KBIC controller. > > It is effectively half of a H-bridge, +5 PWM turns on an opto that > discharges the capacitor, and 0v PWM turns on an opto that charges the > cap. > > As-drawn there is a problem that unconnected PWM turns on both optos... > -- ----------------------------------------------------------------------------- eStore: http://www.homanndesigns.com/store Web : http://www.homanndesigns.com ModIO - Modbus Interface Unit email : pe...@homanndesigns.com DigiSpeed - Isolated 10Vdc I/F Phone : +61 421 601 665 TurboTaig - Taig Mill Upgrade board ------------------------------------------------------------------------------ All of the data generated in your IT infrastructure is seriously valuable. Why? It contains a definitive record of application performance, security threats, fraudulent activity, and more. Splunk takes this data and makes sense of it. IT sense. And common sense. http://p.sf.net/sfu/splunk-d2d-c2 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
