I am replacing a failed converter in an older RV with a 12/12/18 unit. It will draw power from a 400amp Lifepo that runs my AC and fridge and gets a charged from solar and inverter/charger. The original lead acid house battery still runs the lights, furnace, pumps, and accessories. I want to keep this all in place and i don’t want to replace the original converter housing for aesethics. I will be removing the converter and putting the 12/12/18 in it’s place with a direct wire to the positive of the house battery.
I can easily add a remote switch to control when it is active, but was hoping the engine detection capabilities can be reversed.. ie, shutdown when engine is detected and on otherwise. I cannot seem to find any documentation that this is possible.
I assume you are talking about an Orion DC-DC charger? Converters don’t charge. You wouldn’t be the first to make that mistake.
The remote switch will over ride the engine shut down protection. Besides that you can just disable engine shut down protection in settings.
However, I am a big fan of “simple” so here’s an idea. You have a substantial battery bank, you have an inverter/charger( I assume a multiplus). Why not just set this up to run everything from your lithium bank and forego all the extra components and wiring of the Orion and lead acid bank? Lead acid dies hard and fast compared to lithium anyway. So your time is short. Why keep accommodating for a more complex system than necessary? If you are concerned about keeping the lithium bank charged now that it supplies load to other things, spend your money on more solar. Either add to you solar you already have or add another MPPT and more panels. Maybe its time to consider moving on from the lead acid side permanently.