Brushed Heinzmann 250w without controller!

Drunkskunk said:

Bad, bad idea. During start up, the controller limits the current to something reasonable. Without it, the motor will eat all the amps it can get, and fry. During start up, the windings in a motor are essentially a dead short on the battery, with only the resistance of the copper to slow the current down. If your motor has a winding resistance of .001 ohms, then 32 volts / .01 ohms = 3200 amps. That's 102,400 watts trying to go through the motor.

With many batteries, such as Lead acid, their high internal resistance would keep the current from ever getting that high, but Lipo have a very low internal resistance. Likely the battery and motor would both be destroyed. If they didn't blow immediately, there is a real danger that the wires would then begin to burn.

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docnjoj said:

Brushed controllers are dirt cheap from the electric scooter stores. Just put in electric scooter in google and stand back. I haven't used a brushed controller in years, but they work quite OK with brushed motors like Heinzmann. Just don't go over 36 volts or you will burn the motor out very quickly.
otherDoc

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amberwolf said:

waingroo said:

I need some opinions about using a brushed Heinzmann 32v, 250w on direct Lipo source without controller and with a potentiometer throttle instead a hall sensor one.

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Sounds nifty. But the potentiometer is going to be larger and heavier than your battery and motor *combined*.

Look up Luxtrol here on ES
http://www.endless-sphere.com/forums/search.php?keywords=luxtrol&terms=all&author=&sc=1&sf=all&sk=t&sd=d&sr=posts&st=0&ch=300&t=0&submit=Search
for my posts to others about a 1kW version (you'll need a bigger one for yours if you really wanna pour 3kW into your 250W motor).

Here's your new controllerless throttle next to the stator from a an MXUS / 9C typical hubmotor (the motor is lighter and smaller than the Luxtrol dimmer!)

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