From: Victor Tikhonov <[EMAIL PROTECTED]> >John Lussmyer wrote: >> >> At 01:11 PM 10/9/2002 -0700, Victor Tikhonov stated: >> >How does your analog meter averages battery amps? It is not >a DC, >> >it's PWM'ed DC so the error for odd wave form may be as much as 50%. >> >> The little analog amp meter in my Sparrow is small, and does seem to read >> 30-40% low most of the time. I have no idea what kind it is, or anything >> else about it. I do believe it measures battery amps, and not motor amps.
>Yes, its battery amps, but the number is not real. >If you draw PWM 200A pulses 50% duty cycle (like >200A-0A-200A-0A every 100us or so), the average current >is 200*0.5=100A but your analog movement meter may show 60...70A. >A good way to check is to connect a scope to the shunt and get the >average voltage reading ar some load. Divide it by shunt resistance >and you'll get the current your analog meter should show. >Victor This is not true. It is true that an analog meter will not read accurately, but it is correct at 50%!!!!!!! Think about the model. As a matter of principle, think about the model before making any kind of statement about physics. __________________________________________________ Do you Yahoo!? Faith Hill - Exclusive Performances, Videos & More http://faith.yahoo.com
