36v and 48v controller vs speed question

[KirstinS]

I’ve been putting off asking this question , feel a bit daft asking it but needs must !

Short version – all else things being equal will my speed reduce if I replace my 36v KU65 controller with a 48v controller ?

Long version

I have a front 350w BPM, KU65, 36v 12.5ah triangle battery (from BMS) and a 11.1v booster battery (Panasonic cells).

So I’m overvolting. My old KU65 controller it seems was a freakish one-off and my new one is standard. Upshot being – it isn’t coping and is getting very very hot where the old one hardly warmed up under same treatment.

I want to resolve the heat issue but I don’t want to lose speed (or not much anyway).

My guess is I will lose some speed with a 250w 48v controller on my 36v motor but not much. I could make my booster 4s instead of 3s very easily to compensate if need be.

Does this sound right ?

 

[Deleted member 4366]

If you upgrade to the S12S, it's dual voltage, so you can use your battery with and without the booster. By default, it's set to 23 A, but you can turn it down to about 20A in the settings. Can your 36v battery cope with that. It's the battery and motor that make the speed. Sometimes controllers can have slight differences, but the nominal voltage of the controller makes no difference.

Your motor will go a lot better with one of those 48v downtube batteries with the integrated 20A controller. Just £340 for that nice Panasonic one or £250 for the 8Ah one. Go on. You know you want it.

 

[trex]

do you know where to download the datasheet for the integrated 20A controller with that 36V 8AH battery?

 

[Deleted member 4366]

What do you want to know about it?

https://bmsbattery.com/controller/698-sine-wave-controller-for-09-case-controller.html

 

[KirstinS]

I've got a new one of these

https://bmsbattery.com/ebike-battery/683-36v125ah-bottle-09-e-bike-battery-charger-battery.html

It does say 20a continuous

And the booster is the nice Panasonics

 

[trex]

I was thinking of getting this one for my little project:
https://bmsbattery.com/ebike-battery/731-36v10ah-bottle-09-e-bike-battery-pack-battery.html

I have no idea what is included besides the battery and controller, like waterproof cable, display unit etc.
If the item is the whole kit then it's a smashing deal, just add a motorwheel then you have a working e-bike. 20A is plenty enough for my needs.

 

[Deleted member 4366]

Everything is included. You just add a motor, torque arm and spoke key.

 

[KirstinS]

If you upgrade to the S12S, it's dual voltage, so you can use your battery with and without the booster. By default, it's set to 23 A, but you can turn it down to about 20A in the settings. Can your 36v battery cope with that. It's the battery and motor that make the speed. Sometimes controllers can have slight differences, but the nominal voltage of the controller makes no difference.

Your motor will go a lot better with one of those 48v downtube batteries with the integrated 20A controller. Just £340 for that nice Panasonic one or £250 for the 8Ah one. Go on. You know you want it.

Thanks but can't stretch to whole new battery !

Looks like options are

1) that s12s
2) the 48v integrated ( prob should have got in the first place !)

Any need to worry that a 500w s12s at 20a would kill a 350w bpm?

 

[Deleted member 4366]

It won't kill a 350w BPM. BMSBattery used to sell that motor with a 22 amp controller. The S12S uses current control too, so you only get the maximum current on level 5. I've run a 350w BPM with a 30A controller without any problems.

 

[KirstinS]

It won't kill a 350w BPM. BMSBattery used to sell that motor with a 22 amp controller. The S12S uses current control too, so you only get the maximum current on level 5. I've run a 350w BPM with a 30A controller without any problems.

Excellent, thanks

Do you happen to know if it also comes with independent throttle, can see anything on bms website either way ?

 

[Deleted member 4366]

It clearly shows and states a thumb throttle in the controller's listing.

 

[KirstinS]

It clearly shows and states a thumb throttle in the controller's listing.

Sorry
I see it's in the downloadable file - I missed that

 

[awol]

If you upgrade to the S12S, it's dual voltage, so you can use your battery with and without the booster. By default, it's set to 23 A, but you can turn it down to about 20A in the settings.

How do you reduce the amps in the settings?

 

[Deleted member 4366]

You download the LCD manual, which is attached to the S-LCD3 listing. It's all in there; however, I don't know anybody that's confirmed with a wattmeter that it actually works.

 

[awol]

ah, the LCD3, I haven't got one of those (yet)
Thanks.

 

[KirstinS]

I bit the bullet and bought the s12s and a lcd3

Will post results as and when

However, has anyone pulled one open to see inside ? I really don'tneed 20a and would prefer maybe 15 or 17 with longer range

Is there a shunt that can be modded(reverse)

 

[Deleted member 4366]

Yes
The shunt is directly behind the end-plate for easy access.

If you decide to modify it, don't forget that the maximum watts on the display won't change because it'll be misreading the current. You have to check it with an external wattmeter.

 

[KirstinS]

Thanks d8veh

 

[KirstinS]

If you upgrade to the S12S, it's dual voltage, so you can use your battery with and without the booster. By default, it's set to 23 A, but you can turn it down to about 20A in the settings. .

Can I just check if that's a typo d8veh ? 13a not 23a ?

Mine is set to 25a and you dial down in settings by division amounts. The biggest is divide max amp by 2. Which is 12.5a or 13 near as

Or am I misunderstanding

 

[awol]

According to my wattmeter the amps didn't change when I altered the C5 setting. Any ideas?
Is there another setting to change too?