The ONLY place I would connect an inverter is directly to the battery posts or to a set of dedicated lugs that come directly from the battery posts. Calculate the maximum amp draw from the inverter spec sheet and add a fuse to the positive lead for circuit protection. Anything else is a possible disaster in the making, unless you're using one of those small types that plug in to a 12VDC power socket (like a cigarette lighter plug). They are rated for 15 amps MAX. and won't power much.
Lew Farber...RVIA Certified Master Tech...ABYC Certified Master Marine Electrician
SOLAR TECH ENERGY SYSTEMS, INC.
AM SOLAR ...MAGNUM…VICTRON ENERGY...LITHIUM & LIFELINE BATTERIES…MARINE REFRIGERATION