Battery ADD on pack - First Attempt -

[Mind The Gap]

Hi BM
In bed now. I will take screenshot tomorrow do you want it below 3.600 or just above or doesn't matter.

Cheers Paul

[Burgerman]

A graph!

[shirley_hkg]

FMA / XH,EH wiring ?

[Mind The Gap]

FMA / XH,EH wiring ?

Hi Shirley
A mixture of both, could that be the problem.
BM, graph to follow waiting for some help.

Cheers Paul

[Burgerman]

http://www.wheelchairdriver.com/BM3-con ... arging.gif

Long thin cables? Sometimes it will overshoot for a few secs. Target was 3.550V here.

[steves1977uk]

Here's my latest graph...

It balances at 3.598v at the highest.

Steve

[Mind The Gap]

Hi Everyone

It was set to the FMA setting, changed it to XH,EH and everything was ok, the highest it reach was 3.598v.
Have altered the 12v setting to 24v for the lead acid batteries.

Hi BM could you please make me a pre-set for a 18650 llipo pack 12.6v 3s12p and two 12.6 3s72p packs.

Thanks everyone.
Merry Christmas

[Burgerman]

There are lots of different versions of that size. Some are 2000mAh, up to 3500 supposedly. Most are lower than claimed, and much lower if Chinese. Some low resistance, some high. Some are protected with a bms, some not. And LiFe, LiPo, LiCo variants. So details?

Also 3S wont give 12.6V as they are all 3.3, 3.6 or 3.7v nominal. Also these burn and explode so not really very good for powerchairs!

[Mind The Gap]

Hello BM

Usually I balance charge my add on pack with zip file you sent when I attach it to chair for long journeys. Will be using it more frequently in the future so could you recommend PL8 setting for non balance charge please.

8S4P lifepo4 12ah pack.

Regards Paul

[Burgerman]

What cells?

[Burgerman]

8S4P lifepo4 12ah pack.
Regards Paul

8S is a 24V pack. As required for a powerchair. 4P means 4x the cell capacity which means you are using 3Ah cells? 3x 4Ah = 12Ah. Which is nowhere near enough for an addon?

I am confused.

This will charge an 8S LiFePO4 which has a BMS (spits) fitted. But it cant balance the cells and the BMS will not do it fast enough or well enough. Remove .zip

[Mind The Gap]

Hi BM, Sorry BM. Should have read 8s4p 48ah. Remember you saying don't balance charge them all the time so was wondering if you can recommend a non balance setting on the pl8 or non balanced zip file.

Regards Paul

[Burgerman]

You can put back LESS AH than you take out as often as you want. Without balancing.

So if you KNOW you took out 35Ah you are safe to return 25 or 30Ah. But it must be measured. Except in an extreme case. So that you drive toll the cell voltage is under 3 and you can put back 75% of the total Ah.

What you cant ever do is recharge full without a BMS or balance connected charger.