Goosepower
New Member
- Joined
- Mar 15, 2020
- Messages
- 28
Always happy to help folks make ththe jump towards freedom & independence !1. Thank you for your input. You are correct. The system I have designed will cost approximately $4400. Your option is half that. 2. Yes, balancing is top of the list. I have seen a 4s5p 180ah 3.2v system using balancing leads in the "middle" of each string using the ElectroDacus BMS. Your option is, I think, a better one. Also, thank you for the PDF from Victron. This is exactly why I sought out info from this forum. I need the experts to opine. Take care.
To get the most out of your packs and most redundancy the "best" option is to built two independent 24V 8S packs each with it's own BMS and then parallel the packs into one bank. Should one cutoff for any reason the other will keep going, charge & discharge loading is shared equally across both IF properly wired to do so. This excellent doc from Victron explains it all very well. https://www.victronenergy.com/upload/documents/Wiring-Unlimited-EN.pdfFor a 24v system I could use an 8s2p layout.
Thank you Steve. This makes sense. I was drawing up designs that were series/parallel/series and was losing my mind. This type of design you describe would have both 24v banks of 8s cells going to their own BMS and from the LOAD of each BMS tying together on a single bus bar? Correct? This makes balancing each bank very simple. One step at at time. Many thanks.To get the most out of your packs and most redundancy the "best" option is to built two independent 24V 8S packs each with it's own BMS and then parallel the packs into one bank. Should one cutoff for any reason the other will keep going, charge & discharge loading is shared equally across both IF properly wired to do so. This excellent doc from Victron explains it all very well. https://www.victronenergy.com/upload/documents/Wiring-Unlimited-EN.pdf
There you go. relays are MOOT !Today I just received two Daly BMS. They are common port and rated at 200A discharge, 80A charge. I am in an off the grid house in Montana. I have plenty of summer sun but in the winter I can have thick clouds literally for months, so I charge my batteries in winter with an AC generator. I’m lucky in that my system (inverter/charger and SCC, made by Outback power, allows me to control many of the parameters which could be problematic such as maximum charging amperage, maximum discharge amperage. I had lead acid batteries But I am just getting started to change over to lithium iron phosphate. Everything about relays and shunts is completely new to me.
Thanks Steve for your help. And thanks for that link to your previous post about voltage matching. It was really very clear and easy to understand. Take care, MikeThere you go. relays are MOOT !
DO CALIBRATE for Voltage correction !!!
Calibrating Voltage of your system to ensure Optimal Operations. SCC, Inverter/Charger, voltage matching.
Good Day everyone, This is a topic that seems to be generally neglected by not being mentioned or even considered in many posts. This is unfortunate because components such as Solar Charger Controllers, Inverter/Chargers need to "know" the precise voltages being dealt with. With Lead Acid /...diysolarforum.com