EMax 72volts ???

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EMax 72volts ???

Does anyone know if once the stock controller of the EMax has been upgraded with higher rating capacitors, will it run using 72volts ??? If so, what would you think the top speed would be ?? Thanks for everyones opinions, etc. God Bless.

Last seen: 2 months 1 week ago
Joined: Saturday, July 7, 2007 - 23:55
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Re: EMax 72volts ???


the FETs on the power stage are 75v 200A hexfets. a 60v mod is as high as you can go without blowing these.

the caps on the power stage are 63v units, and should be replaced when increasing voltage, although on my setup theyve survived thus far.

I do have a controller where i replaced the FETs with 200v 75A units, and the caps with 100v.
the FETs are in, i just havent got around to putting the caps in.

top speed would be 75-80kmh.

if you were going this route, id suggest buying a replacement kelly controller so you would have more current aswell.


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Joined: Wednesday, November 22, 2006 - 05:44
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Re: EMax 72volts ???

Matt anf JDELUNA,

It is fairly easy simple to add another parallel resistor to the shunt on the e-max controller and raise the current limit. I calibrated the 1.9mm (12AWG) wire from a steel coat hanger (0.049 milliohm per mm). I also wondered if one of those four pots on the board adjusts the current limit. (two are for adjusting the speed restrictor if used)

But with the reasonably priced, better quality Kelly controllers, I agree that there isn't a lot of justification for messing with the e-max controller anymore.

BTW, I found that raising the voltage did not have a much effect on raising the motor torque for acceleration and hills - raising the current limit was also needed to get adequate performance.

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