Solar charging

[Cuppa]

So the dual batt isolator that's listed above is
it much of a difference to the redarc sbl12 or can I keep what I've
got and just get the solar panel setup

Yes it is different, it is a bit smarter than the SBi12 in that it
allows for different charging voltages of different types of
batteries. ie. if your 65ah battery is an AGM it needs a different
charging regime to your wet starter battery. (But it will survive if you stick with what you have)
More importantly it is also a smart
charger which will ensure you have the best chance of fully charging
your 65ah battery when driving (dependent upon how long you drive for). You could
virtually drive for ever using the SBi12 & still not charge the 65ah
above 80%. This is fine for a starter battery, but when you are
relying on having the full capacity to make your fridge use last
longer when you get to camp starting at 80% & not taking it below say
50% means you only have 30%, or about 20ah to play with.

I have two separate systems in our bus, one uses an Sbi24 (24v
version), actually it's a slightly different 2 way version the SBi4D,
which allows the solar connected to the house batteries to charge the
starter batteries, as well as charging the house batteries from the
alternator. (Readily available by special order, but not generally advertised).
In this case though both sets of batteries are AGM's (so have the same charging needs) & the
solar 'tops up' the batteries through the multi stage charger
incorporated in the solar reg. This works ok, because I have plenty of solar capacity for a lightly used system, your proposed system would be more marginal & thus not have the same degree of 'flexibility'. I used to have wet starters but they
didn't last as long due to being overcharged from the solar. The AGM's
survived this regime ok however.

Bottom line is that whilst the SBi12 will work in your situation, it likely wont work well enough, & without doubt can be improved upon. Horses for courses. Depends on the condition of the wallet. For $200 you could buy a panel with a cheap regulator attached & give it a try. If it suits...... great, if not you can throw away the regulator, sell the SBi12 & buy/install a BCDC1220.

Cuppa