Engel Smart Box

Yeah 55 amps is a little on the light side for many people, but if only running a fridge and leds at camp, AND both running the fridge from the car and recharging the Engel battery while driving, you could be ok.

You shouldn't be draining your Optima BTW, only running it down maybe 30% overnight ?

My Arkpak only has a 6 amp 12v charger, and as my 100 amp hr battery only goes down to 83% or so overnight, it charges up by mid arvo when touring.
I run the fridge and charge the ark from the car 12v while driving.

At camp I unplug the ark charger, but leave the fridge on the car system for up to an hour, then plug the fridge into the Ark.

Can you hook up an 80w solar panel to the Engel whilst at camp / base camping ?
This should run a medium size fridge and put 2 - 3 amps into your battery each hour when there is decent daylight.

Surely you did some research and checked out the specs before buying it????

Never had anything to do with Optima batteries but I doubt it will appreciate being flattened completely.

Yeh almost without exception these commercially contrived, packaged battery boxes are very poor value for money.

The chargers are too smal, the inverters if fitted are pissy and the whole thing is over priced.

If ya need a charger .....make your own choice and buy one.
If ya need an inverter......make your own choice and buy one

Appart from that its a box with a small amount of wiring and a few switches and sockets.

Mostly not worth the price being asked.

Most you don't even get a battery.

cheers