# 24v vs 36v 500 watt motors



## major (Apr 4, 2008)

Dink said:


> What are the differences between a 24v and 36v motor, both being 500 watts? Power? Better range? I'm building an e-bike. Would the 36v give the same power but better range over the24v? Both motors are rated @ 2600rpm


Hi Dink,

Things you ask depend on more than just the motor. Taking the motor at your stated ratings for face value, then:

No difference in performance. The 24V motor at 24V gives you 500W at 2600 RPM and the 36V motor at 36V gives you 500W at 2600 RPM. Equal power.

No difference in range, if your batteries were the same type and mass for the 24 and 36V systems, meaning that the energy for the 2 systems is equal (which would be Whr). Obviously the 36V battery would have to be rated at 2/3 the Ahr compared to the 24V battery.

The current in the 24V system would be 50% higher (3/2) than in the 36V system for equal performance. So you would need wires, fuse, and controller rated 50% higher, typically meaning physically larger (and maybe more costly). But this would be of little consequence to you inquiry about power and range 

Regards,

major


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## Dink (Jun 3, 2010)

That answer is exactly what I was needing. I took your advice on the 24v-36v 50amp continious controller question from a previous thread, and bought a KDS-72200. It's probably over-kill, but oh well. I'll see if it makes the little motor scream uncle. I was even thinking of going 24v 900watts, I understand the more power, will decrease the range with the same ah battery pack. I live in hilly western Washington, so hill climbing is more important than range for the most part. I'll only be going 10 miles max on any given trip without a recharge.(average 5 miles round trip) Thank you, Major and all of you at Evnetics. Dink


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## major (Apr 4, 2008)

Dink said:


> Thank you, Major and all of you at Evnetics.


Hey, I'm not associated with those idiots 

Tesseract and I do have a real name in common. And they are not idiots. In fact I am impressed with what Evnetics has accomplished. 

Good luck with your eBike and hope I helped.

major


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## Dink (Jun 3, 2010)

major said:


> Hey, I'm not associated with those idiots
> 
> Tesseract and I do have a real name in common. And they are not idiots. In fact I am impressed with what Evnetics has accomplished.
> 
> ...


 Sorry, I thought you were part of Evnetics. You have been helpfull along with them. What power difference would I have between a straight 36v-500w motor -vs- 24v-500w motor run at 36v? Yes, I tend to abuse mechanical devices.(11 second street legal 65 Lemans) Hill climbing is the first concern. Speed and range second.(daily drive a 88 s-10, 4cyl pickup) Trying to find a middle ground between having my cake and eating it to. With ICE's, Ive found build it for 8000rpm and 600hp strength wise and make it 6500rpm and 500hp, and it will take abuse for quite some time and not say uncle.(with proper maintanice) Looking to apply that thinking to this paramater.


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## rillip3 (Jun 19, 2009)

Dink said:


> Sorry, I thought you were part of Evnetics. You have been helpfull along with them. What power difference would I have between a straight 36v-500w motor -vs- 24v-500w motor run at 36v? Yes, I tend to abuse mechanical devices.(11 second street legal 65 Lemans) Hill climbing is the first concern. Speed and range second.(daily drive a 88 s-10, 4cyl pickup) Trying to find a middle ground between having my cake and eating it to. With ICE's, Ive found build it for 8000rpm and 600hp strength wise and make it 6500rpm and 500hp, and it will take abuse for quite some time and not say uncle.(with proper maintanice) Looking to apply that thinking to this paramater.


It somewhat depends on the motor. The increase in voltage does not necessarily mean a linear increase in power; some of that energy will go to losses in the form of heat. But assuming that it did, 500w = 24v * x. x = 20.84 amps.

W = v * a, so 36v x 20.84A = 750w. Go figure, if you increase the voltage by 50%, you increase the power by 50%. But again, this is minus losses, and it would really depend on what type of motor and other motor-specific issues as to how much it would actually make.


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