What is the purpose of hooking the charge port neg to the BMS instead of right to battery?

Just as I asked. The schematic I have seen hooks the negt to c- or p-.

That is, on a bypassed BMS.

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I would be shocked if you knew the answer. Therefore, it is NOT a noob question. I imagine Battery Mooch or other pro would be the only source.

On the contrary, Evan is one I would most definitely think knows the answer.

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If I answer your noob question, will you use that thread in the future?

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I’ll take that as a yes. I’ll answer your question with a question.

If I wanted a BMS to protect my battery while charging, should I plug my charger into the BMS?

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Whe n hooking up the BMS as intended, usig the power regulation etc, the charge port is simply hooked up to the main terminals, with a fuse on the pos.

So if you plug your charger into your battery instead of the BMS, how does the BMS cut charging in instances of over voltage? How does it balance the pack?

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The battery balances simply as a function of being at 4.2 per cell. They bleed regardless of the charge port being hooked straight to the main terminals.

And again, if hooked up as mfgd. tje charge port is NOT hooked in any way to the BMS.

I suppose that depends on what BMS you’re using, but you lose every other protection. Any smart BMS is configured to only balance when charging. I believe it’s the same for Daly BMS, but I’m not certain.

The BMS only knows it’s charging when you plug the charger negative into it.

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Most folks say that the battery continues to balance after it is charged, which means it balances simply due to the p group being 4.2ish. Dumb BMS which cannot be configured.

The entire functioning of the bleed system SHOULD be within the black on main neg terminal, and all the balance leads hooked to the pos of p groups.

This algorithm continues until all cells are balanced to within the pre-defined maximum difference in voltage and continues even after the BMS has switched off the charger. Once all cells are within this voltage, balancing will stop until power is removed and re-applied to pin 3 on the BMS (i.e. the next charge cycle).

As this states, after the BMS shuts off the charger. My charger shuts itself off. Thus, I guess, hooking the charge port leads, allow the BMS as a backstop should the charger fail to shut off.

I don’t know who is saying that, but it sounds inaccurate. Plug your charger into your BMS.

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This is correct and needs to go to the noob thread. It where we all ask our noob questions, it the question is too complicated it gets pushed out to the more technical threads. @Skatebored why do you not like and use the resources here, it’s set up to make helping each other easier. Not as an insult. Simple questions such this as individual new threads get missed and doing the wrong thing (like bypassing the charge protection of the bms) can trash your shit or burn down your board.

Bypassing the charge protection of the bms will let your charger charge any one group to 5v with one dead or low p group which im sure you can see is a fire hazard. No way the 50mw balance resistor can make up for that. This is basic basic knowledge of these battery systems, it is literally the main point of a bms. There is also a beginner basics wiki that spells this out. Not trying to be rude (tone is hard in text format) but please don’t make the news charging a homemade bomb - we bomb hills not homes here :call_me_hand:

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When I open categories, to put thread, I didnt find a choice of noob thread.

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Because you don’t have to make a new thread for every little snafu. Just post it in an existing thread.

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All good man, learning the site and the ins and outs of good forum etiquette is a process. Just look for my deleted “pictures only “ messages :rofl:

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Also i set the tracking for that and some other threads to the highest level. That way i get notifications and can help out to try and pay back some of the help Ive received there. Also some really interesting things come up occasionally there first and are super insightful. Keeping up on the thread has definitely answered some of my questions before I even knew to ask. Like updating the bootloader when updating vesc firmware, i was stuck on that for embarrassingly too long on my first vesc build lol

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You guys scared the hell outta me with your bomb talk, so I took off my enclosure, and checked every wire, and checked balance. It was balanced, and since I run my switch AFTER the non bypassed BMS, my charge port was hooked to the in of my smart switch. Which is hooked to the p- of the BMS. I did that as it was easier to gang the charge wires there than the BMS outputs.

It had been a while since I wired it, so I doubted myself. HAd I ran my switch off battery, then to BMS, It would be wrong. This is why I wanted to be SURE of my knowledge base.

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