Is it possible to convert a BBS01 250 W to 350 W

Martinvg

Finding my (electric) wheels
Jun 21, 2018
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Hi,

A I am new to the e-bikes conversion kits, and I know little of Volts /Watts / Amps.
So I have Some questions......

Last week I have mounted a BBS01b 250W on my Trek 300T.
Now I have orderd a USB-cable so I can tweak the BBS01b. I think the ‘Keep Current’ has a very low ‘factory adjustment’, becaus it stopts assisting at max 25 kmh (Max speed in display was set to 50 kmh).

First question:
Is it that easy to convert a BBS01b 250W to 350W by just changing the Current Limit from 15Ah to 18Ah? Or do you also have to change the controller software / firmeware? (Or even the controller itself?).

After Reading several forums / topics, there is a change that changing the Current Limit to 18 Ah, can result in a ‘error’ on display or a overheating motor.....

So is the 250W just the same motor a the 350W? Or is the 350W aquiped with a 18Ah controller.

Second question:
My battery is 15 Ah. So is it possible to change the Current Limit to 18Ah? (Because my battery is only 15 Ah).

Martin.
 

Nealh

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Aug 7, 2014
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Hello Martin and welcome seems know one else is greeting you today.
 

Nealh

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It appears the new B versions are throwing up error codes adjusting amps to high, to go 18a you will need to buy the correct rated controller.
The speed is probably limited in the software under PAS tab or throttle tab, often it is set for ' By display command'
but also may be set at 25km/h which you can adjust.
Also the Basic tab may have amp % & speed % set at conservative limits again all can be tweaked with the cable and software program.
 

Nealh

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Battery capacity is ah or wh , controller rating is straight forward amps not ah.
Battery cells have a known capacity in mah. A 3000mah cell is 3ah, these will be connected in parallel. If 5 cells are used then this gives the battery its capacity rating which will be 15ah or 540wh at 36v.

It is the battery cells that define its amp draw rating most likely your battery will have a 25 - 30a rating so will be fine with a 15a controller.

Different cells have different amp ratings, if its rating is 10a max with 5 cells in parallel. Then a battery is rated as 50a max for short periods of use.

Show us a link to the battery you have and we should be able to tell you it's amp rating.
 

peter.c

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Apr 24, 2018
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Hi
Yes you can change the controller but it has to come from china or the states most times uk stock sells out very quickly , but if your lucky and have the unrestricted version of the 250 watt controller you can go to 18 amps Ebyke was lucky his version will adjust my 250watt will not you will not know till you try
 

Martinvg

Finding my (electric) wheels
Jun 21, 2018
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Hi Peter,

When I Connect it to the computer, is there anyhow i can see If it is unrestrickted? Or do I just have to ajust it an see If there is a any error?
 

Nealh

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Your battery is using Samsing 2600mah cells either the 26F,26H or 26J variant, in themselves they are mediocre cells but if as stated there are 60 cells inside then they are configured for 6 in parallel so have max 31a draw for a short period so will be good for 15 or 18a controller setting. The only time the controller will ask for max amps is if throttle is used, pas is in highest assist or when climbing inclines.
 

Martinvg

Finding my (electric) wheels
Jun 21, 2018
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Ok, I thought they where Samsung 30B cells..
So they are not that great .....
In the (low) factory setting the BBS01b and this battery managed to go 95 km.
Wonderig what distance I mannage After tweaking.
 

Nealh

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30B are high voltage 4.3v cells pretty rare in ebike use because of the need for a different charger voltage.

The spec states 60 cells and 2.6ah so you have a 10s6p with 2600mah cells configured inside the case. The actual ah has been rounded up to 16ah but the battery is actually 15.6ah or 561wh.
 

anotherkiwi

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Jan 26, 2015
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Ok, I thought they where Samsung 30B cells..
So they are not that great .....
In the (low) factory setting the BBS01b and this battery managed to go 95 km.
Wonderig what distance I mannage After tweaking.
If you go to 18 Amps and all things being equal you should get 79 km or about 20% less range because you will have about 20% more power (3 Amps is 20% of 15 Amps). You will be able to climb faster or have a higher top speed if unrestricted and the same gearing.

I have run all the numbers and do not find it useful to increase Amps and thus more power from the same volts on my GSM. My choice is to make the motor spin faster by raising voltage - I also get a few more Watts but it is motor RPM before back EMF kicks in that is my problem.
 

peter.c

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Apr 24, 2018
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thurrock essex
Hi there several factories that supply bafang motors and many different versions of what appears to be the same motor, yet alone what spec your supplier ordered :confused: you will not know till you try
. Make a note of the original settings before you change any thing I learnt this the hard way in my rush to tinker:oops:, the biggest difference is the keep current
I think we all have doubts about battery purchases and costs :(
 

Martinvg

Finding my (electric) wheels
Jun 21, 2018
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Ok. Thanks for the reply’s.
I’m awaiting the USB-cable, so can see the settings and make Some changes (After backing up the factory settings).
 

Devon Chris

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Apr 25, 2018
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Devon
Bbs01b here and I also get an error when changing amps from 15 to 18. Looking at replacing the controller and possibly getting a 350w version one from dillinger