battery temp compensation

[vtmaps]

Even though I connect my new panels in sets for total of 24 volts and join all in a combiner box can I still have the battery bank set up as 48 volt. Is there a feature in the midnite that gives me this option or do I have to stick with arranging my batteries as 24 volt system.

You must always configure your panels so that the string voltage is higher than the battery voltage.  Remember, a 24 volt battery may need to be up at 31 volts at times, and a 48 volt battery may need to be at 62 volts on occasion.  This thread is long and I don't remember the specs on whichever panels you are referring to, so I don't recall whether two of your 24 volt panels can charge a 48 volt bank... if it can, you're cutting it pretty close.

If you reconfigure your panels and combiner box so that you have three panels in series, (and the Voc is not too high), you can charge a 48 volt battery.

so the big battery you refer to can either be as you said one big battery or several connected in series as one, right.?

Yes, "Big" refers to battery capacity... doesn't matter how many batteries or whether they are series or parallel.  Of course there is only one battery configuration that is most optimal, that being a single string of battery cells that are large enough to give you the capacity you need.

--vtMaps