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BMS - How do I know why size is fine ?

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May 10, 2021
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Sorry if this was asked before but I received my 8 cells from China. Each is 280 Ah. I am installing them in our 5th wheel camper that needs 30amp service to run the AC and some other items. I plan to buy 8 more cells next year after I get my my feet wet. For now I think 24v is the way to go.
My question: if I buy the BMS recommended in the videos and on this site, it only allows for 100amp or 2400 watts. That’s short of what I need. Does the BMS define how much load can be drawn or is it purely for charging ?
If it defines ultimate load then any suggestions on a different BMS ?
 
The BMS limits BOTH load and charging currents...

what is the 30amp service at? 30amps at 124VAC, 230VAC, 12VDC??
 
Thank you. 124VAC. The AC has a soft start that I installed so it usually draws around 1700 watts at 124VAC on start but then settles at a draw of 11 amps. I know it is probably dumb to even consider running the AC with the batteries but I like the idea of confusing people.
And I assume if I land on a BMS that can handle my setup, all I need it the victron inverter to finish the setup. Victron because of the low draw when idle.
 
Thanks. That’s what I think will be my game plan. Build it as is with this pack and increase amps when I am ready for the second pack. Thanks for the help guys ! Ordered the BMS.
 
Do you mind sharing a link to a good one ? I have no experience and am learning through this setup. Maybe I’ll pickup both and it will force me to keep building. :)
 
Thank you. 124VAC. The AC has a soft start that I installed so it usually draws around 1700 watts at 124VAC on start but then settles at a draw of 11 amps. I know it is probably dumb to even consider running the AC with the batteries but I like the idea of confusing people.
And I assume if I land on a BMS that can handle my setup, all I need it the victron inverter to finish the setup. Victron because of the low draw when idle.
your AC alone will draw 55-75 amps at 24v... you could go 200amp but imo that is too much for continuous discharge... even 100 amp continuous would drain your batteries in 2.5 hours... you need at least 12 hours of battery time between solar charging...
 
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