Originally Posted by sail2liv
Have orig house battery in sealed compartment.....next to it have trailer battery in regular box with jumper cables from an emergency starting battery attached to it....that way if need more amps just raise sealed lid and hook cable to orig house battery.
While your arrangements sound good, the one thing you might want to consider is a 2 way battery switch instead of the jumper cables to the low battery.
If you do jumper to the used battery terminals, the higher voltage battery will discharge into the low battery as they try to equalize. You will quickly find your self with two low batteries.
Better to use a "1 -2 - both" selector (and never use "both" with two different types, or charge state, of batteries).
Note: My batteries were both purchased at the same time and are identical Deka DC-24's - my switch always is Both or Off.
Lou and Laura with Bella - German Short Hair Pointer
2008 GMC Sierra 2500HD Crewcab SB Allison Duramax
2010 Flagstaff 8526RLWS - Superglide 3300
HAM CALLSIGN - KC3FFW