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Started by Muskie1, July 28, 2023, 05:41:55 PM

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 So I have the electro bike world  35 amp controller.  After  25 attempts of setting it up I only ride in Pass 1 at 15 mph showing 95- 110 watts.  2021 Mini 4 . My battery  After 20 miles still 50 with a voltmeter check. WHY.


Fully charged, my batteries show about 54 volts on a meter. You seem to have gone down 4 volts. I keep logs of mileage and indicated voltage. With my Radrunner, I could often go more than 10 miles per volt. It has a 14 AH battery. My Radmission has a smaller battery, but earlier this month I went 24.7 miles between 53.9 and 52.1 volts.

I don't do so well when a battery is below 50 volts and do poorly when it's below 44 volts. It appears that as amp-hours are drawn from these batteries, the voltage doesn't drop linearly.

100 watts would be about 2 amps from the battery. In 80 minutes (20 miles at 15 mph), it would draw 2.6 amp hours. That would draw down a 14 amp-hour battery 19%. Fifty volts seems reasonable to me.

I think it's possible that much of the time, the motor wasn't getting 100 watts. At P3 you can select torque or speed for PAS. I chose torque. On PAS 1, my wattage will increase as I pedal faster and the controller tries to add the same amount of torque.

If I'd chosen speed, the opposite would happen. If you had observed 100 watts at 12 mph, PAS 1 may have delivered much less at 15. Now that I think about it, it sounds interesting. I'll try it!

Around here, streets aren't flat. Unless I have a headwind, I may spend half my time coasting, with no power coming from the battery.


It seems like you are asking why it used so little battery, so let's do the math and find out how much is actually being used.

Your battery is 48v, 14 Ah, which gives us 672 watt hours of storage. 50 volts is 71%, meaning you used 29% of your battery. (672/100) x 29 = 194.88 watt hours used, divided by 20 miles gives an efficiency rating of 9.744 watt hours per mile. That's pretty efficient, and is reasonable if you are in the lowest PAS level and putting in some decent effort yourself. I think your numbers are good. I often ride with PAS adding about 200 watts, and I usually get about 18 Wh/m when riding like that.