52V battery/ 48V controller / 250W motor?

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itslud   1 µW

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52V battery/ 48V controller / 250W motor?

Post by itslud » Nov 25 2019 8:49pm

I was wondering if I can use 52V battery with 250W gear motor with 48V controller.
If the 48V controller is pulling 20A which equates to 1000W but since the motor is rated 250-500W can I cut/shave shunt controller to lets say 10A and that equals to 520W. Is this ok?

goatman   10 kW

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Re: 52V battery/ 48V controller / 250W motor?

Post by goatman » Nov 25 2019 9:38pm

whats the motor? 52v battery is 58.8v fully charged. most controllers are fine upto 61.5v/ max 63v but you tend to blow them at 63v. motors, if its a DD id go for it. I wouldn't want to overvolt a tiny geared hub if I weighed 300lbs and then tried to wheelie it off the line with a fresh battery.geared motors have plastic gears. if youre worried about blowing the motor with a fresh battery go easy on the throttle til you hit 54.6v. you have torque arms? is the motor on the front tire or rear tire

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E-HP   100 kW

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Re: 52V battery/ 48V controller / 250W motor?

Post by E-HP » Nov 25 2019 10:06pm

What are you seeking to accomplish running at the higher voltage, but limiting current? Higher speed, but within the motor's continuous rating?

Here's a side-by-side example, using a Bafang BPM 250 watt motor, using a 52v pack, @ 10A battery current, 20A phase current; compared to the same motor with a 36V pack @ 14.4A battery current, 28.8 phase current resulting in a 1 mph increase in speed (current on the 36V is set so power to the motor is the same as with 52V).

https://www.ebikes.ca/tools/simulator.h ... eel_b=700c

You can play with the simulator to change the parameters to your specs or specific hardware.

MikeSSS   100 W

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Re: 52V battery/ 48V controller / 250W motor?

Post by MikeSSS » Nov 26 2019 1:01am

A 52v battery powering through a 48v controller to run a 250w motor will probably do fine if the motor is producing 250w or less. Like stated above, the motor probably has plastic gears that are made for a load of 250 watts or less.

As a power use example, I rode 15 miles a few days ago, speed average was 12 mph, pedaling some, and average watts were around 132. Starting watts were probably less than 132 because I start gently with lots of pedal effort and the gearing shifted down. Watt use data was calculated from battery voltage initial, voltage final and looking up battery charge percentage for those voltages and from battery capacity. Rolling time duration is used in the power calculation. Luna's site has links to very useful voltage vs percent charge for several different voltage batteries.

There is another consideration, a controller and throttle will deliver some minimum power. Power minimum will be less for 36v than for 48v and 52v. Most riding situations don't use minimum power much if at all, but some situations need a low minimum power level, perhaps less than 52v can deliver.

Using an electric motor at a power level above its design power level is often done but it increases the risk of failure.

Keep us posted on what you do and how it works out.

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motomech   1 GW

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Re: 52V battery/ 48V controller / 250W motor?

Post by motomech » Nov 26 2019 2:51pm

itslud wrote:
Nov 25 2019 8:49pm
I was wondering if I can use 52V battery with 250W gear motor with 48V controller.
If the 48V controller is pulling 20A which equates to 1000W but since the motor is rated 250-500W can I cut/shave shunt controller to lets say 10A and that equals to 520W. Is this ok?
Serious lack of info in this query(Is what you are using a secret?), but here goes.
If we are talking geared mini-motor here, 52V X 20A = 1040 Watts might be a little much, but 52V X 10A = 520 Watts is nowhere near enough.
The 20 A controller might be ok if the rider is careful w/ the throttle. As power goes up w/ mini-geared motors, they start to "hammer", especially w/ square wave controllers. The Hammering is a series of shocks imparted to the motor and can be hard on the nylon gears. If the controller is a KT style sine wave, this combo of components is probably ok. Really hard hitting controllers like an older Grineon or one of Lynn's Mini-Monsters in the 20 to 25 Amp range can really hammer a mini-motor. There is also a risk of melting the phase wires on long uphills, especially if a low-speed range motor (a 201) is not used in a whl. 26" and >.

Another thing is, the LVC (Low Voltage Cut-off) of the 48 V controller will be too low for the Batt. Pack, so the pack needs to have one of it's own.
Motomech

'03 Rocky Mountain Edge 2WD 260 Q100H frt and Ezee V1 rear 2 Elifebike 20A & 25A 9-FET controllers 12S/10Ah Multistar Lipo rear 4Ah Turnigy frt Luna Cyclops Extra lite Alex 24DM rims, Crazy Bobs run ghetto tubeless. 25 mph. Mean Well HLG-320H-54A
https://endless-sphere.com/forums/viewt ... =3&t=83430
'07 GT Idive 4 4.0, Q100C 201 14S LiPoly elifebike 9-FET 20A controller. 23 MPH.
https://endless-sphere.com/forums/viewt ... 4#p1378484

itslud   1 µW

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Re: 52V battery/ 48V controller / 250W motor?

Post by itslud » Nov 26 2019 11:56pm

goatman wrote:
Nov 25 2019 9:38pm
whats the motor? 52v battery is 58.8v fully charged. most controllers are fine upto 61.5v/ max 63v but you tend to blow them at 63v. motors, if its a DD id go for it. I wouldn't want to overvolt a tiny geared hub if I weighed 300lbs and then tried to wheelie it off the line with a fresh battery.geared motors have plastic gears. if youre worried about blowing the motor with a fresh battery go easy on the throttle til you hit 54.6v. you have torque arms? is the motor on the front tire or rear tire
Hey goatman,
The motor is a bafang g310. Does the 63V max limit also applies to the 36V controller as well? It's because I would like to use the 52V wolf pup from lunacycle. No torque arms and the motor will be on the rear. I live in a city so 10-15mph is generally fine with me.

Wouldn't it be more important what amp is being supplied by the controller than the volt? Just concern about the over heating from the battery with the supplied amp so that's why I thought of shunt mod. Or I'm just making this unnecessary complicated and just use 36v battery.
E-HP wrote:
Nov 25 2019 10:06pm
What are you seeking to accomplish running at the higher voltage, but limiting current? Higher speed, but within the motor's continuous rating?

Here's a side-by-side example, using a Bafang BPM 250 watt motor, using a 52v pack, @ 10A battery current, 20A phase current; compared to the same motor with a 36V pack @ 14.4A battery current, 28.8 phase current resulting in a 1 mph increase in speed (current on the 36V is set so power to the motor is the same as with 52V).

https://www.ebikes.ca/tools/simulator.h ... eel_b=700c

You can play with the simulator to change the parameters to your specs or specific hardware.
Hmm, yeah I see that by limiting the amp will decrease the wheel torque and less off the bat from the starting point and even the watt is equal on both parts, there are discrepancy. Higher the amp, the bigger the pull. The battery I would like to get is the 52V wolf pup from lunacycle. 52V battery with 9 mosfet controller that has around 20A, it would net 1000w so that's no good. I think I might have to find alternative source of 36V wolf pup if no controller mod. The motor is a bafang g310.
MikeSSS wrote:
Nov 26 2019 1:01am
A 52v battery powering through a 48v controller to run a 250w motor will probably do fine if the motor is producing 250w or less. Like stated above, the motor probably has plastic gears that are made for a load of 250 watts or less.

As a power use example, I rode 15 miles a few days ago, speed average was 12 mph, pedaling some, and average watts were around 132. Starting watts were probably less than 132 because I start gently with lots of pedal effort and the gearing shifted down. Watt use data was calculated from battery voltage initial, voltage final and looking up battery charge percentage for those voltages and from battery capacity. Rolling time duration is used in the power calculation. Luna's site has links to very useful voltage vs percent charge for several different voltage batteries.

There is another consideration, a controller and throttle will deliver some minimum power. Power minimum will be less for 36v than for 48v and 52v. Most riding situations don't use minimum power much if at all, but some situations need a low minimum power level, perhaps less than 52v can deliver.

Using an electric motor at a power level above its design power level is often done but it increases the risk of failure.

Keep us posted on what you do and how it works out.
The motor is bafang g310. Their description motor watt range is 250-500w so therefore I'm keeping it around 500w although it says 700w limit but rather not accelerate the degrading form overheating. I should have included that I wanted to incorporated small battery pack such as the 52v wolf pup from lunacycle. But it seems its an inefficient to make it work, perhaps find another 36V battery...Thanks for the input. Sure I'll update on how this plays out.
motomech wrote:
Nov 26 2019 2:51pm
itslud wrote:
Nov 25 2019 8:49pm
I was wondering if I can use 52V battery with 250W gear motor with 48V controller.
If the 48V controller is pulling 20A which equates to 1000W but since the motor is rated 250-500W can I cut/shave shunt controller to lets say 10A and that equals to 520W. Is this ok?
Serious lack of info in this query(Is what you are using a secret?), but here goes.
If we are talking geared mini-motor here, 52V X 20A = 1040 Watts might be a little much, but 52V X 10A = 520 Watts is nowhere near enough.
The 20 A controller might be ok if the rider is careful w/ the throttle. As power goes up w/ mini-geared motors, they start to "hammer", especially w/ square wave controllers. The Hammering is a series of shocks imparted to the motor and can be hard on the nylon gears. If the controller is a KT style sine wave, this combo of components is probably ok. Really hard hitting controllers like an older Grineon or one of Lynn's Mini-Monsters in the 20 to 25 Amp range can really hammer a mini-motor. There is also a risk of melting the phase wires on long uphills, especially if a low-speed range motor (a 201) is not used in a whl. 26" and >.

Another thing is, the LVC (Low Voltage Cut-off) of the 48 V controller will be too low for the Batt. Pack, so the pack needs to have one of it's own.
I promise there is no secret lol. The motor I acquired is the bafang g310 and the battery I'm trying to implement is the 52V wolf pup from lunacycle due to its size. There is a phase runner but it's $300... Yep, its a KT controller that I found on ebay with kit options. If the 36V 6mosfet has the same limitation of 60V, I can use the 52V battery but I just have to be careful with the throttle? This is my first hub installation on a single speed for city ride. Maybe just forget the 52V wolf pup and get a 36V wolf pup alternative or ride this one till the motor blows then I can get a bigger one :lol:

goatman   10 kW

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Re: 52V battery/ 48V controller / 250W motor?

Post by goatman » Nov 27 2019 6:57am

I bought a used kit, g310, phaserunner, 48 volt in a 26 rim. no problems. you can always replace one of the plastic gears with a metal one. Id get a torque arm for it though.

itslud   1 µW

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Re: 52V battery/ 48V controller / 250W motor?

Post by itslud » Nov 27 2019 8:27am

goatman wrote:
Nov 27 2019 6:57am
I bought a used kit, g310, phaserunner, 48 volt in a 26 rim. no problems. you can always replace one of the plastic gears with a metal one. Id get a torque arm for it though.
Sounds great, do you know where can I find metal gear replacements? Ill definitely look into torque arms. Thanks for the info.

goatman   10 kW

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Re: 52V battery/ 48V controller / 250W motor?

Post by goatman » Nov 27 2019 8:35am

sorry, it wasn't phaserunner on that, it was a 20 amp grinfinion with ca3. you can try Grin technologies, they sell those motors and torque arms. grin sells their v4 torque arms on amazon (might be cheaper shipping that way) they should have the gears. they sell hall sensors, bearings, torque arms, tires,rims, spokes, they should have the metal gears, you only need one gear not all 3.

goatman   10 kW

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Re: 52V battery/ 48V controller / 250W motor?

Post by goatman » Nov 27 2019 9:25am

actually im not sure if the v4 torque arm will fit that axle, it fits my 3540 but I got one for a mxus xf40/3005rc and it seems a little loose. theres a chamfered edge on one of the sides that I think can be filed for different axles. theres no regen on geared motors so it shouldn't matter. but if you have a loose torque arm with a touch of play in it youll feel the axle move when hitting regen and again when you hit the throttle, so you want a tight fitting torque arm.

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