How many Batteries can the system handle (charge)

[Boudreaux]

Because we researched heavily before we purchased our 29MV, I was leaning toward Solar in order to be prepared for Boondocking. Well, we camped out in the driveway on three separate occasions in an attempt to get to know what in the coach, we can use in one night, and where we would stand the next morning.

Based on what we were able to do on those evening with one battery, I'm not so sure we need a multitude of Solar panels. Perhaps just two or three additional batteries for additional Amp Hours to carry us over through the night in total comfort (minus AC).

My question to those with more experience is: How many batteries can be fully recharged in one day, by either the generator or the truck alternator (while traveling).

Thanks to all ......

[Mustang65]

My first question would be, what was the battery voltage when you woke up in the morning? Was it 12Volts? 12.2, 12.4...? Did you do everything you normally would do while camping plus some? What size battery do you currently have, 85Ah, 100Ah...?

Unlike car batteries that are made to take a rapid charge, deep cycle batteries like be charged slowly over a longer period of time, or the life cycle of the battery(s) can be affected. Your TT's Battery charge controller and SOLAR charge controllers allows this to happen. Depending on the length or your travel each day and how far down your battery was discharged would determine if you will get the battery(s) fully charged. Generators plugged into the TT's shore power would probably have to run 3-4 hours to get a good charge (about 80 - 90%) back into the batteries.

SOLAR is pretty much charging your battery(s) once the sun is shining. My SOLAR panel is charging by 8:30 - 9AM and still is putting out power at 6PM. For us it was a no brainer, I hate the sound of generators and the SOLAR starts automatically and stops automatically without any intervention. I go up on the roof once a week and clean off the SOLAR panel, check the batteries water level every few weeks and that is pretty much it.

As with any system you decide to go with, proper battery maintenance is critical to get the most life out of your battery(s).

Below are a couple charts that may help you with how deep cycle batteries are charged and the life cycle of a deep cycle battery.

One additional item, it is not so much how many batteries the system can handle but how many Ah need to be put back into the batteries based on your usage.

Don

[Boudreaux]

Thanks for the info. Having not been involved in Rv'ing in 25 years, we tried remembering what we would do on a typical boondocking evening after returning from supper while traveling.

We were very frugal in our actions, and wrote everything down. Entered the coach at 7PM, used four lights for four hours, watched the front TV for two hours, the water pump was on all night long, turned on the furnace at midnight (internal temps had dropped to 50 degrees) set it to 65 degrees.

The next morning the house battery was at 12.5. I used it to start the generator. It started well.

I believe the house battery to be a Harris 85 AH battery.

I'm thinking 3 AMG 100AH batteries at 65lbs each would serve us well. For us boondocking is an over-night thing. Two days in a row at the most.

Admittedly the constant (no hassle, no fuss) quite charging of the solar panels are a very attractive thing. Thanks for the info.....

[RoyBraddy]

The rule of thumb for me is have 14.4VDC with the capacity of 17-20AMPS DC Current for each battery in my battery bank if I want to be able to charge them back up to their 90% charge state in a three hour charge period using smart mode charging techniques.

This works great for me charging my three 85AH batteries connected in parallel.

Adding a forth battery it still works fine but take about another hour longer to reach the 90% charge state because I am dividing up the available DC Current with four batteries instead of three.

In my case I can do the 50% to 90% charge state function about 12-14 times when camping off road before I have to charge them to a full 100% charge state which takes around 12-13 HOURS charge time otherwise I may start doing harm to my battery bank performance i.e. they won't last as long when re-charged back up to their only 90% charge state in the three hour period. The 12-13 hours charge time is is too long of a time to run my small 2KW generator so I usually plan my trips to be at home to do the full 100% charge state runs.

My converter/charger is a PD9260C 60AMP Charger setup and I will hook up my 2KW generator to my OFF-ROAD Trailer 30AMP shore power connection at 8Am each morning during breakfast to recharge my battery bank. Then I am good to do this all over again for the next day/night run on my batteries. Usually where we camp here on the East side of the US we run into generator run time restrictions so all is planned to make it one day off the batteries and recharge again the next morning... We never have found a public place that allowed us to run our generator after 8PM... Most often it is 8AM to 10AM in the morning and 4PM to 8PM in the early evening. I usually fudge the 8AM to 10AM time by one hour to get my three hours in... My generator is very quiet anyway... If I only get 2 hours in then I will run everything again for 2 more hours in the 4PM to 6PM during supper... If I don't start out with at least 90% charge state then it gets dark on me before I get to the 10PM to 11PM lights out period.

Thats my game plan at any rate haha... Sometimes it gets dark on me around 10PM at night trying to run off the batteries before going to bed.

Roy Ken