Re: [classicrv] Re: Electrical problem
- Thanks for the suggestion, Bill. Yes, I've done the math and I should be
fine with only a 20A charger. I have 2 golf cart batteries (from Sam's) in
series rated at 210 minutes @ a 75 amp discharge rate. "Managing 12 Volts"
is a book available from Camping World (and others) that I'd recommend for
anyone interested in gaining a working knowledge of some of the technical
aspects of rv electrical systems. It's very easy to read and does a great
job correctly explaining things on a level most of us can read.
Interpolating from a chart in the book, my batteries should be good for about
400 amp hours (to full discharge) at the rates I'm likely to use them. If I
only use 50% of my capacity, I'm good for 200 amp hours, and by my best
calculations, I'll probably never go over 20 amp hours per day usage. (We
really just don't use much electricity). I also don't foresee ever
boondocking more than 10 days in a row (unfortunately!), so my reliance on
the charger should be seldom. It'll mostly do its work in between trips, and
it has a setting for "maintenance" that I can use when the rv is dormant.
I got the charger from Sears for something like $80 or $90. It has a deep
cycle setting, and its max output is 20A. If it turns out that it doesn't
have as much oomph (technical term) as I need, I guess I can always put my
30A converter back in and connect it as you described.
Thanks for the dialogue. It's good to compare notes to be sure we're not
missing any details and you never know, we might inspire somebody else!
- Indeed, I suspect I'm a user of electrons, Tommy.
Rather than reboot my computer, I'd just leave it running and go into
suspend mode. But I was running the laptop from a small 140W
inverter. Those inverters are pretty efficent at high loads, but
that's not true at low loads. The ProSine true sine wave inverter is
good at all power levels. Wish I could afford one. But what the
heck, lots of electrons back in the batteries.
And then the TV and DSS, small loads on my 600W inverter, but toss in
the electric blanket on cold nights and the power goes up. And the
battery charger for the spot-lifter and the battery powered drill
spare batteries in their charger. Need the drill charged, so I can
run the levelers up and down. The radio in the bedroom, on all
night, so I can listen to wierd Art Bell. A couple oscillating fans
and bunk lights for reading and the water pump for those long,
roughing it showers.
The big killer is all those LED's on everything. Seems everything
has to have some dumb indicator to show its on. 20mA per LED and
there goes the battery life. Ten of those little current draw LED
suckers and you have 5 amp hours a day disappearing. One reason I
have a door switch to shut my breaker's LED indicators off when I'm
not looking at them.
And now I've gone to a 1000W inverter, so I can run my little
microwave at 500W, or even the coffee maker and toaster one at a
time. A few days of roughing it and I have dead deep cycle batteries.
And if its cold out and I turn the furnace on, by morning its blowing
cold air. Since the furnace sail switch will shut the gas off, but
leave the blower running to deplete the batteries. One of the
cleverest things I've seen.