We have a 2017 Forest River Georgetown Motorhome. We love the residential fridge. We don’t love that it is shore power/generator only. I am in the planning and purchase phase of switching our house batteries over to lithium and adding subpanle that is inverter powered to keep the refrigerator running. I’d love to share a schematic with you all for some discussion.
Hi Samuel. Welcome to the Community! I would strongly suggest you find a “local” Victron installer or distributor to help you design a system that will work for you, especially since you have a motorhome and will need to properly deal with charging lithium batteries from the engine alternator and possibly eliminating the bridge capability between your lithium house batteries and chassis batteries. There are simply too many details to discuss on this forum and the Community is not a place for seeking broad design assistance.
That said, I have a few comments that you can discuss with your distributor or installer:
- Consider using higher quality batteries
- Use a Lynx Power In instead of paralleling at the batteries
- Use proper fusing as near the battery terminals as possible
- Consider using a 24V lithium bank instead of 12V. High current devices on 12V is just a terrible experience. Use an Orion 24/12-80 to provide 12V DC power to the 12V fuse panel in your existing power center
- If the motorhome has an on-board generator, consider using a Quattro-II 24/3000 2x-120V instead of a Multi with external transfer switch. If the generator is portable then use the MultiPlus-II. Use two in parallel if you want more inverter power. Or, if you have a 30A shore power connection, use a single MultiPlus or Quattro 24/5000.
- If the generator is an Onan then use a generator controller interfaced with the Cerbo GX to automate the start/stop of the generator
- Skip the separate shore power only load center unless you really need that. Most of our customers just have us feed the entire power center and manage the loads themselves when on inverter power
I hope this helps
This is incredibly helpful! Thank you very much! The quattro seems like a no brainer with the switch built in, but I don’t have any experience with 24V systems. I’m also not exactly sure how different the lynx distributor is from the power in (I’d consider T-class). I do have an onan generator and will look at automating that as well. Finally bypassing the inverter panel does make sense, and less work in general. So you would just feed AC Out 1 to the main 120v panel, and not even mess with the DC panel? Outside of stepping down from 24 to 12 v with the orion?
You need to power both the AC and DC side of your power center. 24V is easier and less expensive to install than 12V, primarily due to half the wire size, all things being equal. Do you have a 30A or 50A shore power connection?
It’s 50A
Ok, then I recommend the Quattro–II 24/3000 2x-120v. If you start with just one, then I would suggest you plan ahead to be ready to add a second in the future if you want more inverted power. Oh, and one more suggestion I forgot in my first reply: do not use a Lynx Shunt. It’s terribly innacurate unless you routinely charge to 100%, and by routinely, I mean at least once a week, preferably more. You are better off using batteries that communicate with the Cerbo GX or using a Victron SmartShunt instead, even though it’s not as clean looking as the Lynx Shunt.
All of these are topics you can discuss with your chosen distributor.
Good luck with your project!