Not enough battery capacity with 4 6V batteries

[ralper]

Bluepill,

With using 14.4 volts as your top charging rate you are never going to truly charge the batteries. I know. Been there and done that.
I brilliantly parked in a shady spot in a CG near north rim of the grand canyon in early Sept. this year. It turned out to be rather cloudy too. The second AM before sunup the batteries were down 147 amp hours or about 20%. I had 12.6 volts at the time. I then used lights, furnace and microwave. No problem. I hit the road and fully charged that day. I have 6 Trojan T-105 batteries and 400 watts of solar panels.` This is how truly charged batteries will perform. The #2 wire from the panels to controler to batteries works much better than the #8 wire the experts installed. Since 11/09 when I fixed my system to really work, I never charge from shore power as Solar does a better job. Charge your batteries to 14.8 volts @ 80 F degrees for several hours. With temperature sensing the voltage will go up as it gets colder. Mine go to 15 volts with no problem. I never have to equalize as that only needs to be done because the batteries are not being fully charged in the first place.

What Handy Bob advocates is the honest truth and my system is a prime example.

[WheelingIt]

Agree with ralpher..you need to up that charging voltage and use temp-sensing. Check the specs for your batteries and use that. We went a whole year before we figured that out and always seemed to be short on amps after our first day boondocking. It's simply because our batteries weren't getting fully charged each day.

As for lights I highly recommend investing in LED if you plan on alot of dry camping and love having lights on. They'll reduce your power draw by a factor if 10. We've installed them in all our most-used lights.

[DAN L]

Originally Posted by fillbert

With regards to the florescent light strips...did you did you replace both tubes with one strip or two within the fixture??

i used the 2 strip kit, 240 lumens each strip. cool white, 6400 kelvin. i would have preferred warm white but this works ok for the sink fixture.

[JimM68]

I like the lesd's, they era on my list.

The solar... well, there is just no roi to be had there.
A nice big onan quiet diesel inverter type generator will keep your batteries charged just fine. No one will even hear it running unless the a/c's are on too.

And you can run that genny for a couple of decades before the fuel equals the cost of those solar panels

[Mr_D]

Originally Posted by bluepill

Re: Charging voltage. With "Flooded" batteries (as opposed to AGM), 14.4 volts is considered maximum "normal" charging voltage. 14.8 volts is considered "equalizing" voltage, which should not be used for every charging cycle.

I have never run the equalizer charge on my 9½ year old Interstate U-2200's.

[Dunner]

My understanding is that to "equalize" means to stir up the electrolyte. Me thinks just driving a MH would be enough, but what do I know?

[Mtnbiker1096]

Conservation is key.

[rorr1821]

Originally Posted by Bee950

The more I learn about powering a house on 12V, the more I learn my MH came from the factory with enough capacity to get you from campground to campground.

I have four 6V house batteries and i believe they are 115 amp each. That should give me 230AH total capacity. Multiply that times .6 and you end up with 138 usable amps. The 21 halogen lights in my coach draw around 43 amps for just the lighting if everything is on. (which isnt likely but you get the point) Its a power hungry pig!

I plan to use my MH for business starting in March. I will be on the road and staying in places not anywhere near electricity unless its from a generator, and some of these events are 10 days long.

I am giving a serious look at Solar and also upgrading the batteries to 200amp Trojans. One thing i read today is the Magnum Inverter/charger I have can be programmed to up the battery charge voltage to 14.8 volts. Default is 14.4, so I dont think they are ever getting 100 percent. Is this recommended?

Suggestions? I have until March to come up with a solution

What brand, type battery, and ah rating are your house batteries? What brand and rating is your inverter? Typically OEM use 6 volt house batteries which have a rating between 200 to 230 ah at 6 volts. For example a battery bank of 4 ea batteries rated at 200 ah at 6 volts provides an available bank rating of 400 ah at 12 volts. I have diesel pusher with battery bank 4ea 6 volt batteries which are over 4 years old. They produce available 460ah at 12 volts. I have a residential refrigerator, 2000 watt pure sine inverter and I have sufficient power to dry camp. I do run generator for a few hours each day and I do conserve energy. I am surprized your unit requires so much energy. Have you been able to narrow down what items are the power pigs?

[Bee950]

Well I did call the battery MFG a few days ago. They put the phone number on the batteries, but not the AH rating (go figure) I have 4, 195ah batteries. The cells I did a quick check on with the Hydrometer tested fine.

I have to keep the coach powered up so the furnace will come on when it gets below freezing. That requires the coach to be "on" 24/7. I keep the Gen in autostart so if the power goes off, the Gen will keep the batteries from going dead. This is working good so far ...


I still liek the idea of getting bigger batteries.

[historyljc]

Change out all those halogen light with LEDs and you'll save a bundle in energy use. As suggested already, being thinking in terms of more batteries. It won't be cheap but go to AGMs, I have Lifeline in my coach) and you don't have to worry about which way they're mounted. Add four more and that should give you plenty of run time.

[rorr1821]

Originally Posted by Bee950

Well I did call the battery MFG a few days ago. They put the phone number on the batteries, but not the AH rating (go figure) I have 4, 195ah batteries. The cells I did a quick check on with the Hydrometer tested fine.

I have to keep the coach powered up so the furnace will come on when it gets below freezing. That requires the coach to be "on" 24/7. I keep the Gen in autostart so if the power goes off, the Gen will keep the batteries from going dead. This is working good so far ...


I still liek the idea of getting bigger batteries.

You have a battery bank with a capacity of 390ah (divided by 2). You divide by 2 because you have 6 volt batteries. If you up sized to the Trojan T145 which have 260ah you battery bank of 4ea would be at 520ah. So you gain 130ah.

Here are some options I would consider. If your battery compartment is large enough I would add additional batteries. You must add in quantities of two. So bank can be 4, 6, or 8.

Solar is always an option. I did an analysis of solar and determined it was not cost effective for me, however if you are going to be dry camping for a large number of days in a year it might more than pay for itself. I would suggest you call someone like AM Solar (www.amsolar.com) in OR. Solar panels must be installed correctly with the correct size wire, controllers, etc to maximize the system efficiency.

You need to check your charging system to make sure the setting are correct. I have a Magnum Inverter and battery monitor system with a remote which allows me to make adjustments to charging system. It also allows me to monitor battery state of charge. Not sure what systems you have but your owners manual should tell you. These setting are critical to good battery performance and longevity.

I do not understand your statement "I have to keep the coach powered up so the furnace will come on when it gets below freezing".

The bottom line on dry camping is to conserve by minimizing electrical requirement. For example even when your TV, receivers, or microwave is off they are drawing some power. You need to install kill switches on these items to minimize power draws. Installing surge strips for your entertainment equipment makes it easy to cut everything off with one switch.

Also remember when you draw 2 amps of 120 volts from a 12 volts system you drawing approximately 20 amps per hour from your batteries.

Some thoughts, not an easy solution.

[Sidewinder]

Originally Posted by Mtnbiker1096

Conservation is key.

Mtnbiker; have you lost your mind??? Some people have no idea what you just said. Conservation-----That is an area that you go camping in isn’t it?? That’s the officers that take care of fish, Right???
We have friends that have a motorhome. Strangest thing I ever saw. The entire coach is equipped with “ON” switch’s. They have NO “OFF” switches in the entire coach. Once something is turned on they are happy and not until they have all the “ON” switches working. They boondock but since they use 100 gallons of fresh water each day they have to drive into town and dump. They have no idea why the shower head in the coach has an “OFF” button to stop the flow of water. How can you possibly boondock without the A/C running. “We paid for heat pumps on ours you know”. But to their credit they did cut back to towing a Lincoln Navigator instead of the BMW. So I guess they are trying.
To each his own
If you lined up all the RV’s in the world end to end, someone would be stupid enough to try to pass.

[Scooter]

Bee950: Have you considered a slide-out battery trey with four additional 6v batteries, into a outside compartment that is ventilated?

[jauguston]

No question. If your Magnum can be set for 14.8v DO IT! Mine is there as well as my solar controller. Charging 6 DC-224-6 Fullriver AGM 6v batteries. The temp sensors will take the peak to 15.4v when it gets down to freezing. Fullriver recommends a maximum charge voltage for a 12v pair of 14.9v.

Jim