Keeping house batteries charged

[tk369]

Hi.
Bay Star Sport 3014, 11,100 miles.
I’ve been told that i have to run my generator for 1 to 2 hours before I go to bed to fully charge the house batteries when boondocking.
this would be OK on BLM land but what if I’m in a campsite I don’t think that I should have to run it. It may disturb my neighbors and make hard feelings.
One night I went to bed before I knew about this and I woke up the next day at my batteries were a 5.1 not good.
Any comments?

tk369
jackson hole, wy

[okcnewbie]

I'm afraid often 2 hours isn't even enough to totally charge batteries.

You have to charge batteries one way or another. Inverter/charger, converter, solar, alternator.

I would highly recommend a quality battery meter with shunt. This way you'll always have a pretty good idea what is coming in and out of your batteries and most importantly know how much they have left.

[Deucenut]

Depending on the condition and age of your batteries, 2 hours isn't going to do it. I'm assuming you have lead acid batteries, maybe AGM, but lets just also assume your batteries are brand new. If your batteries are at 80% capacity, 2 hours will likely not get you to 100% as that can take a day or more, depending on your charger. When I boondock, I run my generator in the morning for 2 hours at breakfast so my wife can use a coffee maker, hair dryer etc and then I run it at dinner time for the same reason. Running it at those times will usually get the batteries to about 80% as long as I haven't used anything major during the day. If I run the furnace at night in the spring or fall, the batteries will not appreciate it and most likely will be close to 50%, which for all intents and purposes is dead for a lead acid battery. And my batteries are only 2 years old.


You need to post more information about your coach and your batteries for folks to help you more indepth.

[Mark_K5LXP]

Originally Posted by tk369

I’ve been told that i have to run my generator for 1 to 2 hours
...
I don’t think that I should have to run it.

A battery monitor would go a long way towards knowing when and for how long to run a genset for whatever size and type of battery, for the level of usage you have. If you don't want to hear a genset you can spring for a solar install and work within the bounds of that. What goes out must be put back in, just a matter of what you use.

Mark B.
Albuquerque, NM

[Daryl molly]

When I boondock, I always run generator for an hour in the AM and 2 hours in the PM, otherwise my refridge tells me the batteries are low. My suggestion, get solar charger to prevent noise (in my case, I will run generator and deal with noise, it just does not seem cost effective to invest in solar since I have a generator).

[tk369]

i found that running my generator for an hour and a half before bed, and then turning off my inverter, in the morning my meter reads 12.6.

i talked to several people at an RV repair shop and that’s what they told me to do.

problem not “fixed” but a reliable work around.

thanks for the posted replies.

[Winemaker2]

"this would be OK on BLM land but what if I’m in a campsite I don’t think that I should have to run it. It may disturb my neighbors and make hard feelings."

Are you talking about CGs with no power hook ups?
If thats the case isn't everyone in need of running gens on some schedule?

[PandS]

Originally Posted by tk369

Hi.
Bay Star Sport 3014, 11,100 miles.
I’ve been told that i have to run my generator for 1 to 2 hours before I go to bed to fully charge the house batteries when boondocking.
this would be OK on BLM land but what if I’m in a campsite I don’t think that I should have to run it. It may disturb my neighbors and make hard feelings.
One night I went to bed before I knew about this and I woke up the next day at my batteries were a 5.1 not good.
Any comments?

tk369
jackson hole, wy

5.1 volts?


We typically run the generator until the Magnum indicates the charge type has moved through the BULK and ABSORB cycles to the FLOAT cycle and the float charge rate has dropped below 12 volts. This generally results in the battery bank being at 12.6-12.7 volts. In the morning, we are typically at 12.2-12.1 volts. We have the absorb cycle set for 2 1/2 hours.


We have an all electric coach and the inverter is always on.


You may have something wrong with your charging system. Be sure that all battery connections are clean and tight, and if you have lead/acid batteries, that they have the proper water level. If not, use distilled water and correct this asap. -Paul

[ArtJoyce]

To fully charge a flooded battery it's a 24 he thing. It's that last 2-5% that takes forever.

When dry camping I never have a fully charged battery bank. My method is run the generator in the morning when making coffee for about 1 hour. If I have a good solar day. We are good until the next morning. Otherwise run the gen for a few hours that evening before dark.

[C.Martin]

If you have a Magnum system...then adding the ME-BMK battery monitor and swapping the ME-RC for the ME-ARC gives you added menu items. Not only will you have a better handle on the state of charge...but you can set the AGS to do quiet time top up. It calculates the generator run to top up your batteries before quiet time begins.

It's admirable to be considerate of others...if you are choosing sites, if you look for similar rigs without solar on the roof, you'll be among kindred spirits...each having to devote some time each day to generator charging. If you get parked between a couple of rigs with a bunch of solar on the roof....we'll they may be generator minimalist.

Battery choice makes a difference. Some batteries have more internal resistance and can require a C/10 charge rate...vs those that can handle C/5...all the way to C*5. The higher your bulk amps, the faster you'll get a jump on charging. Once you hit absorb...the peukert constant will come into play...less resistance, more charge in a given period.


If you do this a lot...solar is awesome.