Second 100ah house battery options on vs30 316

[datamile]

Hi 2019 316 with 180amp (non smart I think ) campervan.

I’ve got a 100 amp deep cycle agm wired in parallel with starter battery , and 150w solar on a separate controller.

I’m thinking I need a second 100amp due to fridge load and cloudy days etc.

i understand mb says a max 100ah to match the starter but was wondering the options And damaged / load on alternator.

1 wired the new battery permanently in parallel so all 3 are in parallel.

2 couple of switches so alternator goes to 1 house and solar goes to the other and can swap over.

3 get a cheap ish dc dc solar charger

 

[PeterInSa]

Re (I’m thinking I need a second 100amp due to fridge load and cloudy days etc)
Re Frig, 3 way or Compressor? Re Frig Size?

Do you have a Low Voltage Cut out, ie the Load/Lights do not work if the Battery Voltage goes below say 11.5 Volts, ie Why do you think you need a second Battery.

We have 160w Solar driving a 110 Amp Home Battery with a 3 way Frig 110Lt?, with Solar charging the crank/home battery when at home and stationary and the alternator charging both when on the move.

Years ago, with an Old home battery at 9pm TV goes off ( via Low voltage cut out), connect up Crank to home battery ( insert fuse after taking out dummy), finishing watching the movie and purchase a new home battery next day

 

[Aussie 2002 4x4]

Hi. I suppose it depends how you intend to use the van.

I've got a 270a/h battery bank and 200watts of solar in the roof and another 320watts of solar in portable panels. I can also charge via 240volts .. and I can charge via the alternator but never have.

When I'm free camping, the above capacity is fine for all of the usual draw for days on end and as long as there's good sun for a couple of hours I'll also switch on the 12v water heater.

Driving from place to place, the roof panel keeps up with the fridge ... on a cloudy day there's enough battery capacity to cover the draw (and I could switch over to alternator but never have had to)

If I am in a caravan park I'll run most things off 240volts and plug in the 25amp 240v charger for a bit if necessary .. when I'm in a powered site the batteries only get used for lights, maxxfan and water pump so the roof panel is plenty

Patrick

 

[jaahn]

Hi datamile
The important thing to answer, as Perter has asked is the fridge type and its electrical load. A fridge is on 24/7 so it is really the biggest load you might have compared to the lights, water pump, TV, charging phone etc. Some people solve that problem by using a 3way on gas. Cooking with gas also. Scomo will love you !
Jaahn

 

[datamile]

Dometic crx110 12v fridge. House battery behind a vsr. Only 150w in the roof and a 200w solar blanket. But never seem to get more than 9 or so amps out of them combined. Been free camping for 10 days but a fair amount of driving each day.

fridge needs some vent work I think.

don’t want to kill the alternator but need more power. Think id go lithium in a few years when I can afford the setup

 

[jaahn]

datamile there has been some discussion on this forum about how to wire up the alternator to charge a house battery. Look back through the threads.
My thoughts are you do not need to worry about killing the alternator, it is good quality and a big one. It is also the best charger you have there when the engine is running. It may be too big for charging a single 100Ahr battery.

I have a dumb old 312D and use a VSR for my house battery and a 200W solar panel on the roof. So I have driving and parked covered to charge my 140Ahr LA battery.

I have found our 12V fridge not as efficient as I hoped for. In hot weather it uses a lot of power but the solar is good too. Cheap solar blankets can be not very good at making power.
Jaahn

 

[PeterInSa]

Since we have a 3 way Frig and gas stove 3 gas Rings and 1x 240vac which we do not use and rarely go into a CP, I do not take our 240Vac Battery charger saves weight and space. To me Solar does the job, can always start the Sprinter up if its an emergency battery charge..