Where is the Positive and Negative of this Power Jack? And will it be Okay to use Along side a BMS to charge 12s Lipos?

this is the bms https://www.ebay.ca/itm/12S-15A-Balance-Protect-Circuit-PCM-BMS-for-43-2v-44-4v-Li-ion-Li-Po-Battery-873/323217175378?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649 This is the power jack https://www.amazon.ca/gp/product/B076P97Z2G/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Positive is usually the longer prong

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You have to match it to your charger when you wire it.


its rated at 30v and my lipos are 44.4v total is that okay? cuz i will only be using it for charging

And I got this charger https://www.amazon.ca/gp/product/B0776TDRL8/ref=oh_aui_detailpage_o03_s01?ie=UTF8&psc=1

How does it work like is it going to charge at whatever the charger is giving to the bms?

It should be fine because you will be charging at relatively low current

That charger is only 12v, it will not charge your battery. You need a 12s charger 50.4v

44.4v is the nominal voltage for lithium ion and lithium poly 12s battery 50.4v is full charge voltage. 4.2v per cell

now it makes sense, thanks

something like this https://www.amazon.com/WAOUKS-Charger-Lithium-Auto-Stop-Aluminum/dp/B07G9VHY8N/ref=sr_1_6?ie=UTF8&qid=1535253587&sr=8-6&keywords=12s+lithium+charger

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it is best to fully balance charge your Lipos before connecting them in series and to the bms if you have a hobby balance charger. If your Lipos are not evenly charged before putting them together, the bms will struggle to balance them so that they can fully charge.

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will this one be okay? https://www.ebay.com/itm/50-4V-2A-Power-Adapter-For-Self-Balanced-Vehicle12S-Li-ion-Battery-Charger-Plug/291922334252?hash=item43f7ed522c:g:ckUAAOSwEH9ZZ0u2

I didnt know that, thanks a lot

It will work, it will just take twice as long to charge the pack and those type of chargers tend to get hot while charging because it has no cooling fan or adequate heat sink. Heat breaks down electronics so it will fail eventually.

Okay I see, thanks again for your help, I truly appreciate it.

I started out using Lipos and taking them out to charge them with my hobby charger. Then later I setup my Lipos with a bms for convenience but I found by experience that a good hobby charger balance charges Lipos better than the bms can.

I still have my hobby charger on hand in case I need it for maintenance. It’s a good idea to have one if your going to use Lipos.

Yeah I got one but its just inconvenient, it takes way too long cuz im charging my lipos from the balance leads and there is two of them so after im done charging one i have to charge the other.

You have one, good. Once you balance your packs with it, the bms will be able to sustain the balance. It just can’t do it if the packs get too far out of balance.

Another tip: get some balance extensions to connect to your Lipos and wire to the bms so you don’t have to remove the balance connector from the Lipo pack. This way it will be much easier to do maintenance on the packs if necessary or to replace them if necessary. I set mine up that way and was really glad I did when one of my packs failed and had to be replaced.

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Sure I got those too, thanks boss.

Here is a link to my build thread in case you haven’t seen it.

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