THE BATTERY
Capacity (when new): 3.5KWH
Fully charged voltage: 58.8V
I have 8x 250w solar panels 37.2 voc
4x 100/50 victron SCC
whats the best way to build this system?
asked
48V Nissan Leaf Lithium Battery Pack 14S with 30A BMS
Just looking at the manuals, the 100/50 doesn’t list 48v use. 2 x 100/20 controllers would handle that array.
Try the MPPT calculator to work out the best controller for your panels.
The Nissan Leaf modules normally don’t get replaced until they are down to 60-70% capacity. That means in reality that battery will have around 2.1-2.5 kWh capacity. 2kW of solar seems excessive for that size battery, what are you planning on using the system for?
Thanks Vance
trying to design a system that would keep power and lights on when the grid goes down.
It would not be grid tied only off grid
interesting about the battery was hopping to get more than 2.5 kWh capacity.
I have never used 48v before only 12v systems
I haven’t personally owned any of the leaf batteries, so I could be wrong. I read that Nissan won’t replace batteries until they reach a certain point. If they came from a wrecked vehicle they may be better.
I personally don’t trust second hand batteries as I feel they have been replaced for a reason.
If you already have the 100/50 controllers I would consider going 24v. There is lots of 24v lighting options and if you want 240v, 24v is fine for a 3kva inverter.
24-12 reducers are also fairly common if you need 12v.
Thanks Vance great info
I ordered 2 Victron SmartSolar MPPT 100/20 (48V) with Bluetooth Solar Charge Controllers
should I connect 4 panels on one and 4 on the other?
Yes 4 panels on each.
You will need to put 2 panels in series to achieve a high enough voltage to charge that battery.
paralleling 2 strings into each controller sounds like your best option.
Without knowing all the details of your panels and how they are mounted, I can’t give a definite answer.
If you are using that battery you will also have to find out how to interface the BMS to your system to protect the cells from overcharging/over voltage.
Great advice Vance
The 8 panels are mounted on a flat tin roof
connected 2 panels each with a Y joiner
awaiting the the cable 4mm
37.2 voc each panel
I also have 2 300w panels 38 voc
The battery's bms is 30amps
Does the 2 Victron SmartSolar MPPT 100/20 (48V) charge controllers have a function to turn down the voltage?
The MPPT controllers will need to be set up to suit the battery.
I believe there is also a way to use the ve.direct port to shutdown the controllers if the BMS signals any type of error.
Edit:
VE.Direct non inverting remote on-off cable (ASS030550310) is what is required, check with your dealer for more information
