I have two 12 V 100 Ah SLA batteries that will be connected in parallel (recommended by Will Prowse, https://www.mobile-solarpower.com ) to be monitored by a SmartShunt. Is it correct that I would set the SmartShunt battery capacity setting to 200 Ah? Any comments on my off-grid cabin design are welcome as this is my first solar system install.
200 correct.
Take the positive load from the left battery.
Wire the charge +ve input to there as well.
@kevgermany Thanks. The 'charge +ve' is what? the charge controller? I have a DC Fuseblock (with in-line fuse), Pure Sine Inverter (on same in-line fuse) and a Charge controller (with in-line circuit breaker), all going to the same positive terminal?
Use DC busbars where you connect everything: batteries - each connected and fused separatelly on its positive wire (and battery disconnect), MPPT charger - with a fuse on positive wire, inverter - with a fuse on positive wire, DC fuse block - also itself fused, SmartShunt (with the battery negatives wires on one side and the negative busbar for loads and chargers on the other side).
The cross section area depends on the current (Amperage) you will have. Bigger is better (but more expensive and takes more room). Make sure it is from copper (best would be tinned copper, because it resist corrosion).
The length and number of bolt holes should be enough to connect everything you need (you should avoid to connect more than one wire lung on each bolt, especially for the wires where you have high currents). If possible, plan for future expansion.
Edit:
You wrote that you already have the batteries. Not much to change now, but you still have the option to put them in series (for a 24V system).
Did you already got the inverter, too? What power you have in mind? For bigger inverters, a 24V (or even 48V) system is preferable. The inverter can only used on a certain system voltage (12V/24V/48V) so be sure you make the correct choice regarding the system/battery voltage from the beginning.
Did you find out if the smartshunt is total bank capacity or if it's usable capacity?
