Charging 2 x 3S Lipo's in series: please look over my schematic

@Link5505 - if you don’t want to build your own, you can buy an adapter on eBay that is wired exactly as per my diagram: http://www.ebay.com/itm/Lithium-Lipo-Battery-Balance-Charger-Twins-Adapter-Charge-For-2x3S-Cells-/172181822194?hash=item2816d61af2:g:zwUAAOSw4hdXIDvC

All you have do do is make (or buy) a set of charging leads that connect your charger power output to the Deans plug on the adapter.

Whenever I do this i get a big spark. I’m using turingy 20C 3S 5000mah lipo’s. the ballance wires are : red - yellow - white - black

I did the charge leads first. Then I started to do the ballance leads, but I get a spark whenever my red and black wires touch. This only occurs if the charge leads are connected.

your JST leads are back to front…

and that Diagram probably would have beat mine in the beautiful diagrams comp.

yea, I saw it too just now as I was looking at @trbt555’s diagram and thinking of what i could have possibly done wrong. Silly me.

I did exactly the same thing but sometimes my charger says: error Input voltage. What does that mean and how can I fix this?

Either your Voltage of at least one cell is to low or you want to charge 6S while you have a 5S battery attached.

I have two 3s lipos in series but it could be that one balance charging pin is burnt

@lowGuido I remobed the #4 black wire on pack #1 and charged like I think you say in this post, BUT when I plugged everything in my charger started smoking. The only way to make it work was to use both the Negative #4 on pack #1 and the Positive #1 on pack #2 Thoughts?

sounds to me like you just messed up the order the first time. The order in the balance wire needs to reflect the order of the batteries. You probably just paid more attention the second time and connected them properly.

I guess it is possible… However I tried it 2x and triple checked before I plugged everything in. Also while plugged in the balance charged detected 5 cells… Does that mean it was backwards?

If it started smoking then you hooked it up wrong. That charger is probably damaged now. you would have fried the resistors on the ballance connections.

You need to make sure every cell is in the correct order.

I would’ve thought that too. But once I added the second wire it worked fine. I’m going to take apart the charger and see if there’s anything I can do to fix her up. We shall see…

if its burnt out the bank of resistors you can just replace them…

Yeah I opened it up and the resistors are completely fried. I’m going to try and replace them, but they may have gone through more than just the first layer on the board.

So the fact that those resistors are fried is further proof that you had it wired the wrong way. Mixing up the balance leads puts about 25V across those resistors when there is only supposed to be around 3V.

Yeah I replaced the resistors and it works fine now

Which of these schemes is correct? I’m confused.

I charge 2x 3s at a time it works well

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After making a series connection what side becomes positive and what side becomes negative or dose it not matter?