batteries

A generator always works. Solar, maybe.

Almot wrote:
because generator alone will not get you a proper charging unless you run it day and night.

Another questionable statement.
If your converter supplies 40 amps, three hours of generator time or shore power can give you up to 120 amp hours.
Yes I know it probably won't be the full 120 but running it 24 hours is certainly NOT required for anybody's battery charging needs.

And I am not trying to create an argument here because solar has it's place but what happens if you have 3 days in a row of heavy clouds......or the only camp site you can get is in heavy shade ???

You haven't convinced me yet that a generator shouldn't come first and then solar second.....in most cases.

That's the problem - their real needs are not clear.

On hook-ups a single battery will do, no battery will do as well.

Without hook-ups - too many variables, but I would still prefer more than a single battery. 2*6V or 2*12V (or 3*12V if it fits). Doesn't have to be Lifeline Concorde, but the size (of the total battery bank) matters.

It is possible to stay up to 3 days with a single battery and without a generator or solar if you don't run furnace and high-current items like MW, toaster, hair drier etc. Fridge would account for most of energy consumption then. Many people would call this a "survival mode" and would tell you that this is beneath your dignity, and now that you've spent $$$ on a trailer you have to spend another several hundred (or a few thousand) on other equipment :). Tastes differ.

In case of a single battery I would prefer it as big as practically possible. Batteries are heavy, it is easier to handle 2*100AH @12V than 1*120AH @12V. In other words - there is very little reason to go for a single battery (without hook-ups).

I would also get some solar before the generator - it is cheaper, and it will be useful even if you decide to carry a generator because generator alone will not get you a proper charging unless you run it day and night. With only lights, pumps, radio, occasionally furnace, occasionally small electronics, no high-current items, AND if it is sunny enough, a portable 100W solar ~$300 will keep you afloat for long time. I am not a big fan of portables and think they are way too expensive for what they deliver, but this is an easy way to start for those who are not sure.

You will figure out your needs as you go.

Most people camp with a single 12v Marine deep cycle batteries. If you are on shore power most the time those work fine. They will even get you through a night or two not hooked to shore power depending on the load (generally whether or not you need the furnace). I camped in the smokies for a week on a 12V deep cycle battery without shore power, no furnace, no fans, generally little to no lights on. Water pump, refrig, and water heater were basically the only draw on the batteries. (lighting provided by flashlights, battery operated lantern type lights, and coleman lantern outside).

So the big questions before you go out and spend several hundred dollars, what are your "Real" needs?

Almot wrote:

1: Your old batteries will do. Generator or solar won't be necessary.

What ?? I think you "mis-spoke" there, right ??

badsix wrote:
we will just be using it 3-4 days at a time and in campgrounds with hook ups most of the time.

but will camp with no hook ups some also, just two of us.

i'm going to check out the solar panels. i'm also looking into a generator.

1: Your old batteries will do. Generator or solar won't be necessary.

2: Upgrade to a pair of 6V or 12V - the biggest deep cycle batts that will fit in. Solar will be very useful. Generator - not necessarily, unless you really have to run microwave, or stay without hook-ups longer than 3 days, or camp in the kind of places and weather that BFL13 does :)

3: Depends on #1 and #2.

Joel_T wrote:
BFL13 Haven't forgotten the test on the Powermax Adj single stage / three stage auto. The end of this week maybe. Been caught up in other stuff. In hopes of doing the test I've unplugged the shore cord to get the batts down to 50% so many times I've likely strangled my batts a bit. I unplugged...again... yesterday. Takes forever to get down to 50% unless I turn the heat on a bunch.

Before doing the charger test it is sometimes convenient to also do a load test on the batteries by running them down at their 20 hour rate to the 50 percent level. Measure by SG and resting (after an hour bounce back time) voltage to confirm at 50 percent.

You can do that run down by using DC lights, but be aware the current will drop as battery voltage drops due to the lights dimming. You might need to turn on another light half way through to maintain the 20 hour rate current.

With that done you can read off your AH counter how much is gone and twice that is your capacity. (Confirm again later by AH count on recharging to Full.)

Now you can go ahead and try out the charger, taking amps and voltage readings every 5 minutes until amps taper and every 10 minutes after that. In this case it is especially important to be there when amps start to taper so you know when that happened with this charger in its normal 3-stage profile. Is it different from the old PMs and how different? The thing to note is now how long it stays at Vabs after amps taper and when does it drop to 13.6?

From your info we can draw an ugly graph, or if you have computer skills, you can make a pretty graph. :)

One thing that is commonly overlooked is...

Depth of discharge

Discharge a 6 cell RV battery to 65% remaining, 35% consumed, then fully recharge it after 4 days, a good quality group 27 or 29 battery will give good service including lifespan.

But extract more than 65% remaining or let it sit for a week or longer and things go downhill, fast.

A few years ago I set up a pusher with three dedicated group 31 engine starting batteries to power an inverter dedicated to powering an eleven hundred watt microwave oven. The owner fully understood the pros and cons of the parts and agreed that for his use, the 900 CCA engine starting batteries were the best bet.

Even for a 20-minute defrost cycle, the engine starting batteries worked like a miracle. The bus had lots of solar panels on the roof - I cannot remember the data but the engine starting batteries were not left discharged for many consecutive days at a time.

Golf car batteries can endure mistreatment that will destroy a standard RV battery. But as frequently observed here golf car battery substitution comes at a price, size-wise, cost-wise, and performance-wise (CCA).

Throwing money at the situation to lessen the negative performance points, using absorbed glass mat batteries enters the picture.

Only the owner knows exactly how much load, meaning discharging values he uses. If it's in lighting, LED lamps can be very useful. If it's in a heater blower, then that complicates the equation.

I've seen RVs that consume 5 times the kWh on the road than the owner's home does (no this does not include ranges, refrigerators, or washer/dryers. The rig sits looking like a condo tower at night.

Operating three three ampere fans in direct sun means the entire production of 9 amperes of solar panels. Park in the shade and maybe the fans would not be utilized.

These are the sort of questions that must be asked and answered to arrive at an intelligent plan.

BFL13 Haven't forgotten the test on the Powermax Adj single stage / three stage auto. The end of this week maybe. Been caught up in other stuff. In hopes of doing the test I've unplugged the shore cord to get the batts down to 50% so many times I've likely strangled my batts a bit. I unplugged...again... yesterday. Takes forever to get down to 50% unless I turn the heat on a bunch.

DiskDoctr wrote:
I have a big charger with 200 amp boost, which is 15.1v

Will that help?

Help with what exactly ?

That "boost" setting likely has a momentary switch to activate it, for good reason. It is intended to be used ONLY for starting.