Thank you very much for your replies. I feel very happy each time I get replies from the users list. I also want to use this opportunity to thank everybody here because of the realities that I have sen in EMC2. It is a wonderful game. I tried my first set up and it worked like magic.
I will probably get the 1000Volts scaled down to about 3V because my system gives out 3.3V. Thank you for the components. I will feedback my results to the users list. Actually I'm not new to voltages, I'm a power man, its just that I needed a thorough explanation sometimes like the responses that came did. Thank you. Olusegun Abode +234 8037045535 Email:[EMAIL PROTECTED] --- On Sat, 11/29/08, John Kasunich <[EMAIL PROTECTED]> wrote: From: John Kasunich <[EMAIL PROTECTED]> Subject: Re: [Emc-users] I need to connect my Voltmeter to actually read.... To: [EMAIL PROTECTED], "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Date: Saturday, November 29, 2008, 12:38 PM Olusegun A. wrote: > I'm actually trying to read an analogue signal (High Voltage - > say 1000VAC) being applied to my heavy motor. Do I need an > ADC converter or what is the procedure? How "heavy" is your heavy motor? You need to scale the 1000V down to a range that is safe for typical integrated circuits, probably either +/-10V, or 0-5V. Then you feed that scaled signal to an analog-to-digital converter. Then the digital output of the converter needs to get into the computer (the parallel port is one possible way to do that). Next you need a driver that makes the digital data available on a HAL pin. And finally, you connect the HAL pin to a pin on your PYVCP to make the meter work. To be blunt - if you have to ask this kind of question, you are not qualified to work on 1000V circuits. EMC supports a number of boards with digital-to-analog converters, since all analog servo systems need that. There are fewer analog-to-digital converters supported, but the Servo-to-Go and Vital Systems boards do provide analog inputs. Both of those boards are rather expensive. (see http://wiki.linuxcnc.org/cgi-bin/emcinfo.pl?EMC2_Supported_Hardware) I believe both of those boards expect +/-10V analog inputs, so you will have to do the scaling yourself. Again I remind you that this kind of voltage will KILL you or explode your circuits if you overlook ANY details. Resistors don't just have ohms values, they also have maximum power AND voltage ratings that must not be exceeded. Circuit board clearances for power circuits are much more than you'd expect - they need to avoid arcing over under transient voltages that are much higher than the nominal. A low energy high voltage transient can ionize the air and result in a high energy arcing fault. This is your computer on 480V: http://www.youtube.com/watch?v=-iClXrd50Z8 Regards, John Kasunich ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
