If the meter reads high, it can be lowered with additional resistance in the meter wiring.
The emeter makes several hundred readings per second and then averages them. If you have a high spike (>512 amps) in current, the meter will read low. Joe Smalley Rural Kitsap County WA Fiesta 48 volts NEDRA 48 volt street conversion record holder [EMAIL PROTECTED] ----- Original Message ----- From: "Seth Murray" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Wednesday, October 09, 2002 5:58 PM Subject: Re: Ammeter Innacuracy > Don't say your analog ammeter is unuseful! I think the whole point > behind the analog gauge is to give you a more easily readable > indication of of approximate power usage - when you mash the pedal, it > pins the meter, when you are cruisin' it is much lower. keeping the > meter steady is good, spikes are bad. more accurate readings you'll > want to take off your Emeter. if you want to make your analog gauge > more accurate, I think what it needs is not a compensating circuit but > just a calibrated scale on the face of the meter. I imagine however > that this would be different for every application and therefore not > practical. > > just curious Victor - don't the pulses mostly get filtered out on the > battery side? How does the Emeter stay accurate? > > > Seth > > > > On Wednesday, October 9, 2002, at 08:39 PM, John Lussmyer wrote: > > > At 05:26 PM 10/9/2002 -0700, Victor Tikhonov stated: > >> 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. > > > > Is there any kind of simple circuit I could add to the ammeter to make > > it useful? > > > > -- > > John G. Lussmyer mailto:[EMAIL PROTECTED] > > Dragons soar and Tigers prowl while I dream.... > > http://www.CasaDelGato.Com > > > > > > > > > > > > -- > QUESTION INTERNAL COMBUSTION > > My electric truck page, with lots of photos and a 25 page conversion > journal. Check it out! > http://users.wpi.edu/~sethm/ (no more popups!) > > My EV Album page > http://www.austinev.org/evalbum/387.html >
