Heinzmann 36v 750w controller & battery

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potatop   1 µW

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Heinzmann 36v 750w controller & battery

Post by potatop » Feb 11 2020 5:47pm

Hi everyone, have learned much from the forums from lurking, but it's time to seek some specific help.

I got a Heinzmann 36v 750w 30A hub motor from the local bike coop. I plan on lacing it to a 20 inch rim and using a Crust Clydesdale type fork to upgrade my food delivery bike and hopefully later use it with a larger front-loading cargo bike. This means generous pedal assist on my end, just looking to reduce my fatigue. Frequent hills in my area so I'm hoping the 20 inch rim will provide more torque for hill climbing and I only need to top out at 20 mph maybe. A 20 mile range with me pedalling pretty much all the time would be ideal.

I was considering using a pair of Bosch or Makita or something 18v 5-6 Ah or so, but thinking a readymade battery may be a better option. Any specific bang-for-my-buck suggestions? It's looking like to start, a 4-drill-battery setup (2 pairs in series, then parallel for additional Ah) would work at around $200.

But my biggest hurdle is a controller. Can someone recommend one that'll work specifically for this motor? Am I looking for a 25A controller to stay under the 30A rating? Some threads said controllers for brushed motors are best for these Heinzmann geared ones, but I'm having trouble figuring out what will work specifically.

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E-HP   100 kW

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Re: Heinzmann 36v 750w controller & battery

Post by E-HP » Feb 11 2020 11:21pm

Your motor is brushed, so you need a brushed controller. (verify that you have two big wires, plus maybe a couple smaller ones if there's some monitoring sensor versus a brushless, which would have three big wires and 5 or 6 small ones).

Maybe just do a search on "36v 750w brushed motor controller" or "36V 25A brushed motor controller" on Amazon, and see what you get. Throw in "ebike" while you're at it.

https://www.amazon.com/WOOSTAR-Controll ... r=8-1&th=1

https://www.amazon.com/Bnineteenteam-Br ... HJ1ZQ&th=1

https://www.amazon.com/L-faster-Scooter ... FZEH5FY2HH

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dogman dan   100 GW

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Re: Heinzmann 36v 750w controller & battery

Post by dogman dan » Feb 12 2020 9:33am

Same answer, except it could be from ebay instead of amazon..

Right now though, I would look for a controller already in the usa, vs shipped from china. Partly the virus, but also its Chinese new year over there.

Those motors melt easy when overloaded, so I would limit to 20 amps, so you will get a bit more time before overheat. You will always be overloading that motor if you haul cargo, but the 20" wheel will help a lot.

Melt time for me on those motors has been around 30 min, so be very very careful about hills that take that long to climb.

If there is two tiny wires and two fat wires in the motor, the two tiny ones are a temp limiting switch. Wire your throttle so it goes thorough that switch, and it will prevent a total melt down. So the red wire to the throttle goes into the motor, back out, then to the throttle.

I may be confused about the motor, the 36v ones can take more watts than the switch equipped 250w ones. But I would still say limit to 20 amps,, that is 750w. If you overload that motor, as you plan,,, that means at least 350w of that power is doing nothing but making the motor hot. Put your hand on a 350w halogen light and turn it on.. See how fast 350w of heat gets warm?


wont be so bad on the flat. I'm talking about hills.

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