TommyHolly
New Member
- Joined
- Jun 24, 2021
- Messages
- 207
Hey everyone,
I searched through all the other posts and couldn’t find an exact answer for this.
I need to know:
1. What size BMSs do I need?
2. If I buy four of them, do they connect to each other in some way?
3. What other equipment/wiring/monitoring system is needed?
4. The cost of everything?
I have a 48-cell system I’m rebuilding. Each cell is 3.2v 100Ah. I plan on building four large 12-cell 3P 4S, so each battery would be 12v 300Ah. And the entire battery bank would be 1,200Ah 12v. I was told I would need a separate BMS for each of my four 300Ah 12v batteries for my system.
I have three Outback Solar Controllers charging the system. A Flexmax 60A, a Flexmax 80A and a final Flexmax 80A.
I will also be using this with a 3,000w Xantrex Charger/Inverter. (6,000w max surge)
I’m guessing I would need at least four 200A BMSs?
Here is my math and reasoning, not sure if this makes sense??? 6,000w max surge on the Xantrex at 12v would be 500A. Four batteries in parallel with each having its own 200A BMS would be 800A. Even if one battery/BMS dropped out, I think I’d have enough so the system would continue to run.
Better yet, four 250A BMS for a total of 1,000A. If let’s say two of the batteries/BMS dropped out, I’d still have the minimum 500A remaining to run the system. Does that make sense?
I currently have one 500A DALY 4S LiFePo4 Smart BMS and was hoping I could buy three more and they would work with each other. I don’t know if multiple BMS needs to work with each other? I also don’t know if the four batteries need to be balanced in between one another???
I searched through all the other posts and couldn’t find an exact answer for this.
I need to know:
1. What size BMSs do I need?
2. If I buy four of them, do they connect to each other in some way?
3. What other equipment/wiring/monitoring system is needed?
4. The cost of everything?
I have a 48-cell system I’m rebuilding. Each cell is 3.2v 100Ah. I plan on building four large 12-cell 3P 4S, so each battery would be 12v 300Ah. And the entire battery bank would be 1,200Ah 12v. I was told I would need a separate BMS for each of my four 300Ah 12v batteries for my system.
I have three Outback Solar Controllers charging the system. A Flexmax 60A, a Flexmax 80A and a final Flexmax 80A.
I will also be using this with a 3,000w Xantrex Charger/Inverter. (6,000w max surge)
I’m guessing I would need at least four 200A BMSs?
Here is my math and reasoning, not sure if this makes sense??? 6,000w max surge on the Xantrex at 12v would be 500A. Four batteries in parallel with each having its own 200A BMS would be 800A. Even if one battery/BMS dropped out, I think I’d have enough so the system would continue to run.
Better yet, four 250A BMS for a total of 1,000A. If let’s say two of the batteries/BMS dropped out, I’d still have the minimum 500A remaining to run the system. Does that make sense?
I currently have one 500A DALY 4S LiFePo4 Smart BMS and was hoping I could buy three more and they would work with each other. I don’t know if multiple BMS needs to work with each other? I also don’t know if the four batteries need to be balanced in between one another???