I posted a draft design here prior to knowing much at all about a few things - particularly batteries. I appreciate all the advice I've received since then, and I'm posting an updated design with the hope of critical commentary. I'm sorry for the false start.
Again, the off-grid site is at 43 deg N latitude, and is a year-round home with a 6.9kWh per day usage. Largest load is the well pump, currently propane appliances, HWH and heating.
Some people here are against parallel battery strings, but to get 48V @ 715 Ah +/-, I resorted to two strings of eight 6V batteries. On this point, I planned for 2 days capacity at 50% DOD. I chose a Rolls 375Ah, which gives 750Ah. Alternative suggestions are welcome. I am near the capacity of the 80A 600V MPPT. With MPPT loss, I figured 4225W charge power maximum, which at 57V would be 74A. Too close?
By the way, I used fuses in the combiner due to the high voltage - the max MS breaker is 150V as far as I could tell. I will have 250V+. I was hoping I could rely on a disconnect near the combiner, so that fuse replacement could be done open circuit and then the circuit reconnected.
The XW4548 is discontinued, so I replaced it with the XW5548. As far as generator size, I can't find any efficiency vs load data, but I was hoping that at over 50% of the 6000W capacity for the bulk phase, I will be OK.
Thanks again for any advice, including something is undersized, oversized, etc. Don
Again, the off-grid site is at 43 deg N latitude, and is a year-round home with a 6.9kWh per day usage. Largest load is the well pump, currently propane appliances, HWH and heating.
Some people here are against parallel battery strings, but to get 48V @ 715 Ah +/-, I resorted to two strings of eight 6V batteries. On this point, I planned for 2 days capacity at 50% DOD. I chose a Rolls 375Ah, which gives 750Ah. Alternative suggestions are welcome. I am near the capacity of the 80A 600V MPPT. With MPPT loss, I figured 4225W charge power maximum, which at 57V would be 74A. Too close?
By the way, I used fuses in the combiner due to the high voltage - the max MS breaker is 150V as far as I could tell. I will have 250V+. I was hoping I could rely on a disconnect near the combiner, so that fuse replacement could be done open circuit and then the circuit reconnected.
The XW4548 is discontinued, so I replaced it with the XW5548. As far as generator size, I can't find any efficiency vs load data, but I was hoping that at over 50% of the 6000W capacity for the bulk phase, I will be OK.
Thanks again for any advice, including something is undersized, oversized, etc. Don
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