On Tue, 2007-10-09 at 10:33 -0600, Sebastian Kuzminsky wrote: ... snip > > I don't have an oscilloscope, just a cheap multimeter, so I don't think > > I can accurately measure the current just at spinup time. > > Or wait, would this work? I'll put the ammeter inline with one of > the motor leads, and set the duty cycle to just below where it'll turn > the shaft.
Be careful. Most meters, I am familiar with, can't handle allot of current. You will blow out a fuse if you go beyond the limits. Check the meter carefully to find how and how much current it can measure. I have quite a few meters around here that have blown fuses that I haven't fixed yet. You may want to get a low Ohm resistor with sufficient wattage, put it in series with one of the motor lines and measure the voltage across it. Then calculate the current with V = I * R. A mechanical meter would be handy for filtering out some of the AC, if needed. Others here may have a simple way of filtering the AC on a digital meter. Maybe place a capacitor on the line somewhere, but a capacitor acts like a short circuit on voltage changes, so I would have to think about it to make any suggestions. > The power is pulsed so current varies over time, but the > ammeter should average it, right? Maybe if I put it in its AC mode? AC mode will only give you an idea of the magnitude of the AC component of your signal. It's good for checking how much ripple you have on a DC supply. > > I'll try this tonight. > > Bonne chance. -- Kirk Wallace (Hardinge HNC lathe, California, USA http://www.wallacecompany.com/machine_shop/ ) ------------------------------------------------------------------------- This SF.net email is sponsored by: Splunk Inc. Still grepping through log files to find problems? Stop. Now Search log events and configuration files using AJAX and a browser. Download your FREE copy of Splunk now >> http://get.splunk.com/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
