Are low voltage controller more effecient?

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auraslip   1.21 GW

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Are low voltage controller more effecient?

Post by auraslip » Aug 25 2012 1:00pm

I know that low voltage fets are supposed to have less resistance than high voltage fets. Does this really make a big impact on a bike?

I was also hopping someone could point the way to a low voltage (48v<) controller rather than the 4110 fet equipped controllers most people.
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skaplan   10 W

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Re: Are low voltage controller more effecient?

Post by skaplan » Aug 25 2012 2:20pm

Grin (ebikes.ca) offer infineon 20a and 35a controllers set up for 24-48v nominal. I can't say whether it helps the efficiency, but they're a very reputable source.

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Jeremy Harris   10 GW

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Re: Are low voltage controller more effecient?

Post by Jeremy Harris » Aug 25 2012 3:22pm

If you want to run at around under about 60 to 65V, then pretty much the best FETs around are IRFB3077s, as they have about 25% lower on resistance than IRFB4110s, so will run a little cooler. They won't run 25% cooler, because a fair bit of the loss will come from FET switching loss, but in my experience the 3077's seem to run pretty cool all the same. Those in my 30 A, 6 FET controller barely get warm to the touch even when run hard at full throttle for a fair time.
Please ask questions on the forum, rather than by PM, as it helps others and you'll get a better range of answers.

auraslip   1.21 GW

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Re: Are low voltage controller more effecient?

Post by auraslip » Aug 26 2012 7:38pm

Awesome thank you jermery. That's the info I needed.

I'm trying to build a high efficiency bike from the ground up, so it doesn't make sense to use a high voltage capable fet.
THANKS TO EVERYONE HERE WHO TAUGHT ME ABOUT EBIKES. I'M IN YOUR DEBT.

I sell Ebike Brake levers and throttles with custom connectors crimped on! $10 shipped!

ES facebook group

r/ebikes ebikes on reddit

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