There are some recommendations the voltage be set at 11.0 - 11.2V. Some people think this is far too low, and it is, when the battery is not under load. However, if you have loads on the batteries, such as fridge, coffee pot, etc., the load voltage can easily drop below 12V temporarily, while the battery charge is still well above 50%. You may need to do some monitoring and testing based on what you plan to be running while you are dry camping.
Here are some charts that may help in terms of battery voltage and time it can take for the generato to charge the batteries based on the house battery capacity in yoru coach. When the battery is charging the voltage will be above 13V but the key is allowing the generator to run long enough so the Converter can charge the batteries back to a full charge.
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