Voltage reduction

flecc

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Oct 25, 2006
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You need to tell us what sort of motor, wheel hub or crank and if the latter, exactly what make and model it is.

With a hub motor just changing the voltage from 48 to 36 alone will lose you 25% of the speed, so your motor assist might only reach 12 mph.
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Plas man

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May 12, 2022
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thanks for the reply .
I was planning to use as a second battery for my recently convertet Raleigh Max - 36v 26'' rear hub - a cheep set up of ebay , purchased seperate was a youse 36v downtube batt .

The battery is off my Erider 15 at 48 volt li-ion , so with the loss of power & speed probably not woth the expence for a voltage converter .
 

flecc

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Oct 25, 2006
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thanks for the reply .
I was planning to use as a second battery for my recently convertet Raleigh Max - 36v 26'' rear hub - a cheep set up of ebay , purchased seperate was a youse 36v downtube batt .

The battery is off my Erider 15 at 48 volt li-ion , so with the loss of power & speed probably not woth the expence for a voltage converter .
Since the controller is already a 36 volt one, you wouldn't lose any power or speed. But as you say, it really isn't worth the cost and hassle of voltage conversion just to get some use of that 48 volt battery. Best sell it instead.
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Nealh

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The used value of a battery wll be not great and then there is posting, it woul dhave to be colection only.
The simplest option is to replace the controller with a dual voltage one with a compatibe display then it doesn't matter which battery one uses 36 or 48v.
 

WheezyRider

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The used value of a battery wll be not great and then there is posting, it woul dhave to be colection only.
The simplest option is to replace the controller with a dual voltage one with a compatibe display then it doesn't matter which battery one uses 36 or 48v.
In many cases you can get away with using the 36V controller with the 48V battery, on the understanding that the LVC will be wrong. So long as it has caps rated to 63V, you are usually ok.
 

Plas man

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Thanks guys for the reply’s , the 48volt battery is in my e-rider 15 moped and as I thought I don’t use the moped the battery could be used on my ebike , but maybe best to sell the moped .
 

Nealh

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In many cases you can get away with using the 36V controller with the 48V battery, on the understanding that the LVC will be wrong. So long as it has caps rated to 63V, you are usually ok.
In many cases it is prudent to check the in-rush capacitor rating first before connecting 48v, some 36v ones are only 50v rated.

If one tried a 48v battery on a 36v BBS01 then £90 odd quid will be needed for a new controller.
 
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WheezyRider

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In many cases it is prudent to check the in-rush capacitor rating first before connecting 48v, some 36v ones are only 50v rated.

If one tried a 48v battery on a 36v BBS01 then £90 odd quid will be needed for a new controller.
Yes, always need to check first! :)
 
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Plas man

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thanks Nealh & WheezyRider , but my electrical knowlage stops at re - fuse wire-ing the fuses in the consumer unit and re-wireing a plug .

is there a simple way to test with the meter and the ends of the controler wires ?
 

Nealh

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With metal box contollers often one simply unscrews the four small screws on the back and peers through to see the large capacitor, it will have 50 or 63v noted on it
 
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Plas man

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had the magic box to bits and took a photo of the capacitor .

there is no LCD display on the handle bar only a twist throttle with on/off switch and 3 led's .
(also cut off on both brakes)

also a photo of the moped battery ....


IMG_2968.JPGIMG_2969.JPG
 

Nealh

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Looks like one is in luck both capacitors showing a 63v rating.
 
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Plas man

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thanks Neilh , I'll get the wire/fuse sorted and report back - it could be a couple of weeks .
 

Plas man

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not done anything with the battery yet - but have bought a new front wheel to improve the worn out rim to improve the fromt brake , so for 25 quid now have a shimano dyno hub , also the wheels come in other sizes same price , working great , no connection to seller just satisfied customer .