I am currently planning a system upgrade of my 2022 Valor 37v13 from basic solar to a complete system that can run all loads (120V and 12V). Considering going 24V on the DIY batteries but I am struggling to elegantly solve for high current 12V loads: balancer jack pump slide motors, and genny start. Jack pump states 50-100A fuse and the gen is typically 300 CA.
Any recommendations or experience?
I have 24 volt chassis and 24 volt house bank and inverter setup, with common 12 volt items such as water pump and lights etc. My generator is 12 volt starter which I have a separate LA battery just for that with a b to b charger to keep it maintained. I use a 24/12 70 amp converter for the 12 volt house loads. You could run multiple 24/12 converters to meet your high 12 volt load requirements. I like having a dedicated battery for the generator. Redundancy can be a good thing. More things have to fail to leave you totally dead in the water.
A lot depends on the size of inverter and how close the house batteries can be to the inverter. You can get by with a 12 volt battery system with 3000 watts of inverter and under about 1 meter of cable between the inverter and batteries.
You might consider leaving the high current 12 volt loads connected to the chassis battery and provide a smallish DC-DC charger from your 24 volt house battery. You may also want to charge the house battery from the tow vehicle's 12 volt system (which may be connected to the 12 volt chassis battery), so a second DC-DC charger for that direction, or a bidirectional DC-DC charger.
It's a toy hauler and will have 1200W of solar on the roof so do not need alternator charging. The batteries will be very close in the same compartment. From battery to victron inverter, cable would be 4/0 (12V) or 2/0 (24V). The battery bank is currently designed as a 912ah 12V unit . My thought is I need 70ish DC 24V-12V converter. Just not sure if it would handle the higher loads from the devices mentioned above.
You could also consider using 12 volt batteries in series for your 24 volt house bank and use a vanner battery equalizer between them. Attach your 12 volt loads to the center of the series string. No additional batteries to have to buy or maintain. That is the setup I had before I went to parallel victron and the 24 to 12 step down converter, and dedicated generator start battery. Worked well for years.
