By Tony K
After almost killing my batteries in the middle of nowhere and having to shut off my fridge in the process made me realize that my batteries will not hold their charge indefinately. Especially when my rig sits without running while the fridge is running constantly.
Now I do have to give a lot of credit to the weather as it was almost 100 degrees out. And add the fact that we were parked for almost a day and a half before I ran my rig again. These two factors just about did in my deep cycle batteries, even if it was only temporary. Now I do have to admit I was with plenty of folks who could have jumpstarted my rig but I just don’t want that to be the case should the same circumstances happen again.
Where this is heading is the realization that I need something to keep my batteries charged when I am parked for an extended period. I really have no desire to carry a generator just to charge up the batteries and if you think about it I already have a generator, its called the engine… So the next most logical step is to use some sort of solar supplement to keep the batteries charged. And all I have to keep running is a fridge not a whole bunch of gadgets so I won’t need all that much extra.
So an experiment with some solar extras has now started. My boss at work has a large solar array on his boat and he says it will power everything he uses on the water and more but I am not after replacing the power set up in my rig, just a system that will keep the batteries topped off when needed. Primarily to prevent having to shut off my fridge if I decide to camp for a few days. Besides what good is a fridge if you can’t run it.
The first thing I have to do is find out just how much my fridge draws. This will tell me just how long can I run it and still get the rig to start. And starting my diesel includes more than just turning over the starter but also requires having enough juice to fire up the glow plugs. And lucky for me one of the electrians at work has an amp clamp so I can see exactly what it takes to run my fridge.
While the book for my fridge says it can draw 7 amps on startup, I know it uses far less than this once it is cold. It also depends on the outside temp. I use this fridge on a daily basis to keep my lunch cold and it hardly runs even when it is hot out. But it never sits more than about 9 hours without firing up the rig to get home.
One of the other things I need to do is find out how long it takes with my rig running to recharge the batteries to the point that I can shut down the rig for another day.
The first unit I am going to mess with is a small battery maintainer. My boss loaned it to me. It only puts out 1.5 watts or about 1/8th of an amp. I am a little doubtful that it will keep up with the fridge but we will see. I have been wrong before so there is hope. I am starting out small as I do not want to install a solar sail just to charge my batteries. I want to just have a small unit that can be pulled out and keep my batteries topped off.
So stay tuned, there will be much more to the story….
