BMS/CA (Cycle Analyst)

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mark133   10 W

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BMS/CA (Cycle Analyst)

Post by mark133 » Feb 10 2018 6:10am

Is it okay to run my bike with out a BMS and rely on the CA & controller to control the LVC and Max amps?
I would obviously use the BMS to charge the battery.

Thanks

Mark

liamcaff   1 kW

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Re: BMS/CA (Cycle Analyst)

Post by liamcaff » Feb 10 2018 8:27am

Yeah - I've been doing that for about 4 years now :)

mark133   10 W

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Re: BMS/CA (Cycle Analyst)

Post by mark133 » Feb 10 2018 11:15am

Thanks

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amberwolf   100 GW

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Re: BMS/CA (Cycle Analyst)

Post by amberwolf » Feb 11 2018 3:45am

As long as you have a well-balanced battery, with all cells approximately equal in capability, it's easy to run without a BMS. That's how I run with the EIG cells.

If you have an old battery, or a cheaply-made one, it's more likely that you ahve some groups of cells taht will run down faster than others. Especially if you're running the pack close to it's limits (running it hard). I wouldn't run the old 18650 pack I have without a BMS, for that reason.

In those cases, without a BMS, you have to know how much less capacity you actually have than it's rated for, so you can watch taht with the CA. Also, how much less total voltage you'll end up with because of those groups being lower sooner than others.

footbaldd   100 mW

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Re: BMS/CA (Cycle Analyst)

Post by footbaldd » Mar 09 2018 8:35am

So it is important to note, that the BMS is monitoring for individual series branch low voltage per cell set-points. The CA is monitoring pack voltage. You could easily pass the low voltage set-point on a set of cells and not trigger the CA. That would be less of a concern on a lower voltage pack like the 3s and 4s batteries I use in R/C; however, could be a major issue at 24s for example. Long story short, it will not adequately protect the battery from over-discharge. Do so at your own risk. If they are of equal capacity and well balanced it should work fine, but I would not like that approach.

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