BMS for a 12v system with 2 Victron 12/3000 multiplus in parallel
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sunshine_eggo
Happy Breffast!
6000W/12V/.85 = 588A
I doubt even your cell interconnects (bus bars) can handle that current unless you've gotten very creative with custom bus bars.
Do you mean DIY 2000Ah 12V battery?
Why on earth did you go with 12V?
I'm assuming you have several cells in parallel, something like 7P4S if using 280Ah cells. You likely need to break your bank down into individual 4S batteries, each with their own BMS.
I doubt even your cell interconnects (bus bars) can handle that current unless you've gotten very creative with custom bus bars.
Do you mean DIY 2000Ah 12V battery?
Why on earth did you go with 12V?
I'm assuming you have several cells in parallel, something like 7P4S if using 280Ah cells. You likely need to break your bank down into individual 4S batteries, each with their own BMS.
On a 12V system I won't go over 2000W, 3000W only for short periods. Especially with 6kW 12V makes it near impossible to do properly. 500+A is a PITA to handle. Any crimp with the slightest resistance will cause issues when pulling this amount of power.
Go for 24V or preferable 48V if your setup is over 5kW. Makes wiring a lot easier and a whole lot cheaper.
Go for 24V or preferable 48V if your setup is over 5kW. Makes wiring a lot easier and a whole lot cheaper.
Yes 7P4S. We have 12v in the boat that's why
.
John Frum
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Does that mean big dc loads like bow thrusters and windlass?Yes 7P4S. We have 12v in the boat that's why
No we cook electric 240v. All the other systems are 12v like windlasses
John Frum
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If I'm understanding correctly on top of the ~600 amps to run the inverters you have to supply the windlass as well which will be a significant pure dc draw.
Will be following your work on this one.
48V would have been a better choice. I'm guessing you don't want to change the inverters now?
What is the FLA (full load amperage) of the stove/kitchen appliances in the RV?
sunshine_eggo
Happy Breffast!
Yes 7P4S. We have 12v in the boat that's why
Break it out into 7X 4S batteries, each with their own 120A BMS.
Thanks.
Max 5600watt
My plan is 3* 4s. So each pack has 8 cells of 304amp. Parallel on 1 bus bar. The 2 Multiplus in parallel and other things like led lights, navigation equipment etc connected to the bus bar. For the winches I make a 4s pack stand alone. what do you think?
sunshine_eggo
Happy Breffast!
2P4S? That means you'll only have 360A of output.
Assuming this is with the one leftover 4S. What kind of surge do your motors draw. Motor surge is 4-10X the running current in most cases.
sunshine_eggo
Happy Breffast!
Each battery is limited by its BMS. Each battery BMS is limited to 120A. 120A * 3 = 360A
150A is the RUN current. When it starts, there is a much larger surge current.
For the 4s (winches) I have a Daly 250a smart BMS
I think of connecting Inverter directly behind the (main) fuses (so 3 times), configure inverter to stop at a safe voltage for the batteries. The Victron battery protect I can use for other (DC) loads to protect the battery.
I think of connecting Inverter directly behind the (main) fuses (so 3 times), configure inverter to stop at a safe voltage for the batteries. The Victron battery protect I can use for other (DC) loads to protect the battery.
....and if the BMS will operate continuously at 100%
My expericnce with winches is 150 is FLA and they don't start under load. Motor and gearbox are made to lift the chain/anchor and not pull the boat.
I'd put the Multis on 1 bank and everything else together.......navigation equip. eats up a chunk of power.
Thanks I have to find out how much they use
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