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07-23-09, 02:47 PM
#4
GTALuigi
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Join Date: Sep 2008
Location: GTA
Posts: 764

Bikes: Dahon Mu SL 08 / Matrix 08

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if you were to measure it without doing much match, and/or testers devices.

you can simply find a long straight flat path, or a school field/track and run loops on it, until the battery runs out of battery, on a fully charged battery.

to get a better measurement use pure electric power to go around the track field, until the battery gives up.

average school field tracks are either 200m per side, or 400~500m for the full loop.
pick a known track & field you know well, or you can measure the distance before hand, using a cycle computer or whatever.

so by using Time, distance, volt & watt from the batter/motor spec, then you can get a pretty good approximation.

for example my battery 36V (9.6 Ah) capacity and the motor is 350w, my average daily round trip distance is 90km, ride time is aprox 3.5hr to 4hr, on an average speed of 31km/h
so assuming we are running at maximum capacity 350W/36V=9.72A/s
9.6A * 3600s = 34560 As
34560As / 9.72As = 3555.5As provided in 1 hour
3555.5A * 4h = 14222.2Ah consumed after 4 hours
14222.2Ah / 90Km = 158Ah per Km
that gives me 158Ah/31Km/h= 5.1A/s average,
which is pretty close, as i don't always max out the motor/battery, i usually have 1~2 bars of battery left at the end of the trip.