Q1: If we wanted to buy a generator just for charging the batteries for the TT, what size generator would be needed? Q2:How long do the batteries generally last while dry camping?
A1: My recommendation is either a Honda (2000) or Yamaha (2000) generator. Yes, they are more expensive than others, but they are quiet and reliable. If you go cheap, you'll regret it later.
A2: It all depends. The general rule is that you don't want to use more than 50% of the battery amp hour (ah) rating. With a single, "standard" 12V RV battery (105ah), that means you will need to re-charge after consuming about 50 ah. If you're very conservative on your battery usage, you might get 2-3 days of use before a re-charge is needed. To increase the time between charging, you can use two batteries. If you do so, make sure both batteries are of the same type and in the same condition. For two 12V batteries, you'll be connecting in parallel and you calculate your total amp hours by adding the amp hours of each 12V battery. So, two 12V 105ah batteries connected in parallel yields approximately 210ah. For two 6V batteries connected in series, you don't add the amp hours as is the case for the 12V batteries -- your amp hours are as stated on the single 6V battery (eg, 210 ah).
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