OK, now that you know all about batteries and charging, lets put some
of that stored energy to use. There are a lot of things that you can do
to make your RV home more comfortable and energy efficient. There are
a few projects illustrated to spur your creative urges.
One of the most useful items that you can add to your RV is
inverter. Inverters make 110 volt AC power from your 12 volt battery
This will allow you to operate many of your appliances and accessories
that require AC power without the noise and cost of operating a
Inverters range from simple portable units that plug into your
lighter to larger, hard wired units that are permanently installed. AC
wattage ratings are available from 100 watts up to 4000 watts or more.
About the only thing that you won't be able to operate with a suitably
sized inverter is your air conditioner... the huge size of the battery
bank required makes it impractical. Most other appliances are fair
Picking the right inverter isn't difficult. You need to decide just
it is that you wish to accomplish and how much battery capacity you
Sizing. Let's start by determining what
it is that you want to
operate. Here's a table listing some of the more common appliances and
their wattage requirements.
13" color TV
19" color TV
1250 brew, 200 warm
It's obvious that your microwave requires quite a
lot of power.
Most ovens will draw 650 - 1000 watts. Starting surges can be as high
1500 watts. If you want to be able to use your microwave with your
your inverter should be capable of producing at least 1000 watts and be
rated for a 1500 watt surge. If you want to be able to use resistance
appliances, like a toaster oven or electric coffee maker, be sure that
the inverter you choose has a high enough rating. Most of these
will require 1200 to 1500 watts. They don't have a starting surge, like
motors or microwaves, but are hungry for watts. When in doubt, consult
the owners manual for the appliance or check the ratings plate for
Now is a good time to discuss just what these wattage
mean in terms of 12 volt battery power. First, we need to do a little
Hey, wait... come back here! I promise that it will be simple and won't
require you to buy a scientific calculator to figure it out! What we
to do first is figure out how many DC amps the inverter will draw when
it's making that AC power for your appliances. Put simply, for every
watts of AC power that your inverter is producing, it needs to draw
10 amps from your 12 volt battery system. For inverters rated at 90%
the number is closer to 9.25 amps per 100 watts, but for ease of
just assume that 10 amps DC per 100 watts AC... it's easier to figure
way and errs on the side of safety. For those of you who just MUST have
the math, here it is: Watts =
Volts x Amps, so
= Watts / Volts. For an inverter, operating at 90%
conversion can be represented thus: AC watts / 12 volts X
= DC amps
Example... television drawing 100 watts operating on an inverter will
draw about 9.25 amps from your batteries..
100 / 12 X 1.11 = 9.25
The reason that this is important is that you only have a fixed
in amp/hours available from your battery bank. A pair of 6v deep cycle
batteries or a pair of group 24 RV batteries will have a capacity of
200 amp hours. That means that if you run that TV from the previous
for about 20 hours, your batteries will be flat! 9.25A X 20
Still with me? Good! Using the chart on wattage requirements
our new-found knowledge of amp hours, lets take a shot at how many amp
hours of battery bank we need to supply us for a standard days use.
13" color TV
Don't forget that you are also using power from your batteries to run
Volt lighting, fans, water pump, etc.
You begin to see that putting in a larger inverter to run
will require you to have an appropriately sized battery bank and an
method for recharging it! You can't hook a 2000 watt inverter to a
battery and cook the Thanksgiving turkey in the microwave! You should
a feel for your intended inverter usage and take into account the size
of your battery bank before selecting an inverter. In my personal case,
I chose a 750 watt inverter to go with my 2 battery bank. I didn't have
room or weight capacity for more batteries, so I went with a smaller
It runs all my electronics, charges power tools, runs kitchen tools,
won't support my microwave or toaster oven. It was a good compromise
my situation. It was also a lot cheaper, as my inverter was about $500,
compared to the $900+ that I would have paid out for a 1500 watt unit.
And that brings us to the next topic:
Hybrid Systems. Often, it is
more cost effective to purchase
a smaller inverter to run the small appliances that you have and use a
generator to power the more watt-hungry larger appliances, like the
and coffee maker. This will give you quiet power for most uses and
the wear and tear on your generator. If you can't manage a full sized
bank and large inverter, this hybrid approach may work better for you.
It is the approach that I chose to use, and it works well for me.
Inverter types There are 3 main
types of inverters. Square
Wave, Modified Sine Wave and True Sine Wave. Let's look at the
Square Wave inverters are the cheapest.
are usually the least efficient and will not run any of your electronic
equipment. The reason for this is that the AC waveform they produce is
very different from what you get at a standard wall outlet. Instead of
being a sine wave it is a square wave. These inverters are usually
for power tools and motors, but will not work with your TV or stereo.
Modified Sine Wave inverters are the
middle of the
road. They produce an output wave form that is close to a true sine
and will work adequately with most devices, including TVs and
You may be able to see some slight distortion lines on the TV or hear a
slight buzz on the stereo, but for the most part, these inverters
quite acceptable performance. One noted exception is that most laser
won't work properly with a Modified Sine Wave inverter. They are also
as far as cost goes.
True Sine Wave inverters are exactly
produce a practically perfect sine wave output. These units will
even the fussiest electronic device, but they are much more expensive
their cousins, the Modified Sine Wave inverters. Do you need one?
not, unless you simply MUST have the best, or are trying to get a
sensitive piece of equipment to work in your RV.
Battery Charging. Many of the
better inverters designed
for RV use are also high quality battery chargers. This is an excellent
option, as it allows you to get rid of that old, inefficient converter
and enjoy faster, safer 3 stage charging. Most of the major inverter
offer this either as standard equipment or as an add-on accessory on
inverters. These chargers typically can deliver from 25 to 150 amps of
charge current and run very well with generator power, allowing you to
quickly recharge your batteries while out in the boonies. These 3 stage
chargers will also not boil the water out of your batteries. Instead,
will bring them to full charge and then taper back to a true float
these units can safely be left plugged in continuously, unlike the
converter found in most RVs.
Costs. You can expect to pay about $50 to
$100 for a small portable
MSW unit. RV designed units start at about $500 for a 750 watt
and go all the way up to units rated at more than 3000 watts and
several thousand dollars. Price increases with wattage ratings and
The best thing I can suggest is to do some research. Check the links
below for inverter manufacturers and remember to size the inverter
on your real needs.
an inverter. I'm going to take you through the
that I did for my RV. Your needs and situation will be different, but
should give you some ideas. A word
of Caution: Always
follow the inverter
manufacturer's installation guidelines, paying close attention to
wire sizing. Installing an inverter requires understanding of safe
practices and electrical safety code. If you don't have the necessary
get a qualified electrician to do the wiring. Don't
Mount the inverter in a
compartment where it
will be accessible and safe from moisture and flammable items or gases.
Inverters utilize some components that can create a spark, so never
install an inverter in the same compartment as the batteries! I
mine in the forward compartment underneath the 5th wheel overhang.
The next step was to wire the AC side of the inverter to the rigs
system. One of the advantages of an installed inverter is the
of AC power at the same outlets that you're used to using when plugged
into shore power. I simply chose the wall outlet circuits that I wanted
the inverter to power and modified the rigs breaker panel to
my choices. The Heart Interface inverter that I chose has a built in
switch on the AC side. The transfer switch supplies AC line power to
inverter's AC output when plugged into shore power and then switches to
the inverter when shore power goes away. It's all completely automatic.
I used standard 12-2 w/gnd Romex and fittings to wire up the AC side of
my inverter... you will need to supply AC power to the inverter and
the inverter's AC output to the circuits that you want to function when
shore power goes away. This is really simpler than it sounds, so don't
worry. Your inverter installation manual will give you some basic
of installation wiring. Here's a wiring diagram of my installation
is taken right out of the Heart Interface manual:
The wiring to the battery is done next. After removing the original
and it's wiring, I installed heavy duty battery cable to connect the
directly to the batteries. It's important to use heavy enough wire
as some larger inverters can draw several hundred amps when under full
load! My inverter required 6 ga. wire. I also twisted the heavy wire to
help eliminate any electrical interference when operating the unit in
mode. A fuse was used to protect the system from meltdown. I used a
fuse connected directly to the positive terminal of the battery as
Once all that was done, I ran some wiring for the remote on/off switch
for the inverter function. This lets you disable the inverter when it's
not needed. You could really leave it on all the time, but the inverter
does draw about 1/2 amp in standby (when there is no load on the AC
so I would rather turn it off when not in use to save power. I mounted
the switch next to my monitor panel (more on the monitor panel
as seen here.
Some of the larger and more
expensive inverters offer
very sophisticated control panels that will tell you battery voltage,
rate, amp hours used, you name it. Very handy, but somewhat expensive.
A little further on I will share some tips about constructing your own
monitor panel, like I did. In use, the inverter is almost like being
in! I can charge my laptop batteries, watch TV or a movie on the VCR,
my kitchen appliances, and all without the noise of a generator. Truly
a great addition to your RV if you ever park far from the nearest AC
For even more detailed information on inverters, go see Phred
Tinseth's Inverter Poop Sheet on the subject. Phred
will give you
a lot of great (somewhat opinionated) information on the whole process
of choosing an inverter. Well worth your time if you're thinking of
one! Also, stop by and read some of his other Poop
Sheets... Fred is a fine source of information and
he has many
articles on a variety of RV related topics. A very useful resource for
all you Rvers out there!
A big advantage for those of us who spend some time away from
hookups is the addition of one or more solar panels to the roofs of our
rigs. Solar panels will provide power to charge your batteries whenever
you have sunlight. This can extend a dry camping period almost
and solar is quiet and non-polluting. Even a single panel will help a
I have a single 55 watt panel, and it provides almost 6 amps of charge
current when in direct sunlight. That doesn't sound like much, but
that 6 amps by 10 hours and you're doing some serious battery charging!
Several solar panels, a good sized battery bank and an inverter will
you with many of the luxuries of hookups and will be silent and
The only drawback to solar is it's cost. A single 50 or 60 watt panel
cost you as much as $400 and larger panels are really pricey... still,
it's an attractive option for those who like to spend a lot of time
A solar system consists of one or more solar panels connected through a
charge controller to your RV 12 volt system. Sunlight striking the
generates power and the charge controller monitors the battery voltage
to prevent overcharging. These systems are extremely reliable and
Sizing. The number and size of solar
panels may be determined
more by your pocket book than any other factor. For all it's
solar remains very expensive. It is definitely worthwhile to have at
a single panel, at least 30 or 40 watts, just to keep your batteries up
in storage. A single 50 or 60 watt panel will, in the summer, provide
with as much as 60 or 70 amp hours of charge per day. For those who
to be truly hookup independent, a number of larger panels coupled to a
larger battery bank will provide you with plenty of power, even when
have an occasional cloudy day. Cloudy days are the bane of solar
Even a high thin cloud layer will cut your charge current by 50% or
and you'll only get 10-20% of rated power on an overcast day. This is
more panels will help. Most authorities agree that if you calculate
daily average energy usage and then provide enough solar capacity to
your daily use by 25%, you'll be all set. Let's think about that a
If you take that daily usage table that I did for the inverter section
and add the calculated additional 12 volt appliance and lighting use,
can come up with a figure to work with... see below
13" color TV
12 Volt lighting
6A (4 ea. 1.5A bulbs)
12 Volt pump
12 Volt fans
Grand Total AH >
Looks like we'll need to replace about 140 amp hours (AH) of
day. If we figure that a 60-75 watt panel can produce 60 to 70 AH per
under perfect conditions, then it's reasonable to assume that the same
panel will produce an average of about 35 AH per day, due to adverse
conditions, time of year and other factors. Some days are sunny, some
cloudy..... For planning purposes, we can figure on that average
per panel,of about 35 AH a day. Looks like we'll
need at least
4 panels up there, and probably would be better off with five panels.
is always some loss of efficiency when recharging a lead acid battery
a couple of cloudy days will really hurt your overall charge
Looks like we will either have to conserve power a bit better, or do
serious investing in solar panels. The truth is, the above example is a
bit on the energy extravagant side, but illustrates that it's easier to
use power than it is to replace it! My own small system, consisting of
a single 55 watt panel, provides adequate power to keep me in business
for a week, provided that I am conservative and don't have cloudy
If it's cloudy, or I have poor exposure to the sun, I have to run the
for a couple of hours every few days to charge the batteries.
There are a number of very good sizing
on the web... RV
has one you should look at... click
here to check it out... Or consider their Rule of
Thumb: "The average
RVer, one without unusual needs, generally finds that one 4
and one 105AH battery (or equivalent) per person provides an adequate
for long term outings. An extra panel and battery provides insurance
bad weather and enough power to handle the unexpected."
Hybrid Systems. Again, sometimes the best
answer is a compromise...
a small solar system to save $$ on panels and a small generator to take
up the slack when needed can be the most cost effective way to go. I
an Onan Microlite 2800 Watt genset... it'll just barely run 1 roof A/C
unit, or anything else in the rig and uses very little gas. In the
with good exposure, I can go a week easily without hookups, using the
only rarely. It's an approach that you should consider....
Mounting. If you're going to put solar
panels on your RV roof,
you will be faced with several problems... the mountings must support
panels safely and must hold them on the roof in the face of 70 MPH +
It is also preferred that the mounts don't cause your roof to leak!
are several types of panel mounts that have been designed with RV use
mind. Use them! If you do design your own mounts, make sure that they
capable of keeping your panels attached securely to your RV. Some of
available mounting systems provide for tilting the panels in one
to allow you to maximize output by facing them directly at the sun.
they only tilt on one axis, you will have to orient your rig to take
of this... not always possible. One school of thought is to mount the
flat on the roof and simply use more panels to make up for the lack of
efficiency. I chose to design my own mount for my one panel, using a
length hinge along one side of the panel and a standard crank up TV
assembly to provide for tilting the panel. I can crank up the panel
inside the rig to the best available angle and lower it flat to the
for travel. This arrangement has worked well for me, and the panel is
up there after more than 50,000 miles. The panel is mounted to take
of the 5ver's roof line and gives me a wide range of tilt angles.
Wiring. Now that your panels
are on the roof, it is necessary
to get all those electrons from the panel to the battery. Best
is to use as heavy a gauge of wire as possible to reduce losses on the
line over distance. Even though my panel maxes our at under 6 amps, I
10 ga. wire to connect it. Bigger (within reason..) is better! Another
problem is how to route the wires into the RV. Drilling holes in the
is always to be avoided when possible, and it just so happens that most
RVs offer some convenient alternatives. If your panels are near the
roof vent, route the wires down through the roof vent opening and into
the interior of the rig. It's also possible to use a plumbing vent. For
my installation, I used the black water tank roof vent pipe as a
Once inside the RV, the wire can be routed to the location of the
bank and connected to the charge controller.
Controllers. Although it is
possible to directly connect
the solar panel(s) to the batteries, it is much better to use a charge
controller. This device protects against overcharging of the batteries
and also provides a diode to prevent reverse current flow to the panel
at night. These controllers can be as fancy as your pocketbook can
or very simple. The simple ones will usually cost in the $50-$75 range
and do the same job as the fancy ones with the meters and computer
The controller simply hooks into the charge wiring between the panel
Most RVs come standard with a little analog battery meter or a small
LED display. These meters aren't very accurate and aren't much use if
really want to know what's going on in your 12 Volt system. One
is to purchase a good quality hand held digital volt meter and use it
monitor the voltage from your batteries. The drawback to this method is
that you have to hook it up to your batteries whenever you want to take
a reading. A better solution is to install a small digital panel meter
and permanently connect it to your batteries. This way, the information
is right there at your fingertips. There are a number of these battery
monitors available. One place you can look to see some examples of
available is at the Backwoods Solar Electric Systems website.
for a look at one of their catalog pages featuring meters. Most of the
solar equipment retailers offer a variety of meters to suit your needs,
but they can be a little pricey. Still, for an out-of-the-box solution
complete with installation instructions, they're hard to beat. You can
expect to pay $40-$50 for a simple panel voltmeter and as much as
hundred bucks for a really sophisticated system monitor. At the bare
you should have an accurate voltmeter... even better is to have a
to monitor your battery's state of charge and an ammeter to see what
of current is going to or from your batteries.
Some of you may be thinking: "Why should
to pay such close attention to my batteries? Can't I just sort of
them and hope for the best?" Well, sure you can! The problem is that
you're dry camping and dependent on your batteries for all of life's
conveniences, it's real easy to use more juice than you put back in...
sort of like overdrawing your checking account. The addition of a volt
and amp meter will allow you to see how much current you're taking out
of the batteries and how much you are putting back in via solar or
charging. When I installed an ammeter, I was amazed at how much current
just a few lights draw, not to mention other 12 Volt items like the
and water pump. It's definitely better to know for sure what's going
If you plan to install, or have already
an inverter, you may be able to purchase a very nice monitoring panel
an accessory to your inverter. Most of the major brands designed for
have this option available. It can tell you all you need to know and
even have provisions for outside source charge monitoring, from solar
for instance. It's worth checking into and will save you having to
your own monitoring system. See the links above in the inverter section
and check out some of the manufacturers webpages.
One alternative for you tinkerers out
there is to
build your own! Simple, battery operated DC panel meters are available
for under $10 and with a little work, you can have a very nice 12 Volt
panel meter for cheap! A little more work and you can cobble up a very
functional volt/amp meter. Let's see how:
a simple DC Voltmeter for your rig.
This is a simple volt meter that is easy and cheap. The
meter runs off
a single 9 Volt battery and is very easy to build and install. You can
connect it to just about ant wiring in the rig that carries unswitched
12 volts and it's small enough to fit just about anywhere. The parts as
listed are available from All Electronics Corp. They have a website at
and you can download their catalog in PDF format and view it.
3 1/2 digit digital voltmeter, panel mount, battery operated, 200mv
scale. Can be purchased for about $10 from All Electronics Corp.
Part # PM-128
Small toggle switch, SPST, pick up anywhere, Radio Shack, your junk
etc. All Electronics Corp. Part # MTS-4 will do just fine.
9 Volt Transistor radio battery.
9 Volt battery connector. All Electronics Corp. Part # BST-8
1 100 Kohm resistor 1/2 watt 0.5%
1 9.99 Mohm resistor 1/2 watt 0.5 %
Follow the directions included with the panel meter. The resistor
values listed above are the correct ones for the meter available from
Electronics Corp., but your meter may specify different values to use.
The resistors are installed in holes provided on the meter circuit
to form a voltage divider to set the range of the meter to 0-20 Volts.
The meter instructions will explain how to do this. Attach the battery
connector as specified in the meter instructions. Install the small
switch on the battery connector + lead... this is used to turn the
on and off. You can omit this switch and have the meter on all the
but it will run down the 9 Volt battery in about 6 months. I chose to
the on/off switch on mine. Mount the meter in your rig in a convenient
location, preferably near a 12 volt source. Closer to the battery is
but not super critical. Connect the meter input leads to the 12 volt
A fuse would be a good idea if the circuit that you connect the meter
isn't already fused. A 1 amp fuse will be way more than enough, as the
meter draws practically no current. See below for a diagram.
a DC Amp meter for your rig.
This is a little more difficult, but worth the effort. The
as was used above can also be used to measure DC current if a device
a Shunt is used. Put simply, a shunt is a very accurate, very low Ohm
that is placed in the DC positive line directly off the battery. By
the voltage drop across the shunt, we can determine the amperage
We will be using the same panel voltmeter as above to build
meter. Some basic wiring ingenuity and the use of a suitable switch
allow you to use a single panel meter for both functions... more on
later. First, the shunt must be built or purchased. You will need a .01
ohm shunt, one that's rated 10 mvolt / amp. Shunts are available from a
variety of sources, but you can also build your own! I constructed mine
from a set of 10 .1 ohm 10 watt precision resistors
wired in parallel
to produce the desired .01 ohm resistance. The
resisters are connected
by bus bars made of 4 strands of 12 ga. solid copper wire and the whole
thing is connected using 8 ga. wire. See the pictures for more info:
The Block diagram for the ammeter looks like this: The meter, set up to
it's 200mv full-scale range will measure up to 20 amps using this
A change in the meter resistor voltage divider will give you a range to
200 amps, but less resolution. I wouldn't recommend passing 200 amps
this homemade shunt, but it's capable of carrying 50 or 60 amps without
frying. The 20 amp scale works well for me, but the one downfall is
this shunt and meter combo isn't large enough to allow the inverter to
be hooked up through it. I originally designed this setup long before I
had installed the inverter. It's still a very useful setup and may give
some of you tinkerers out there some ideas for a design of your own....
Here's a wiring diagram that I used to build my volt/amp meter for my
This allows you to use the one panel meter to monitor both amps and
When I designed my monitor panel, I wanted to have
everything in one
location. The panel has controls for the generator, the volt/amp meter,
controls and indicators for the solar panel and a handy 20A cigarette
socket with a circuit breaker for heavy duty 12 volt loads. Whether you
buy one or build one, it's really worth your while to have at least an
accurate voltmeter in your rig to allow you to keep tabs on your
condition while dry camping. It will extend the life of your batteries
by preventing too deep a discharge and will give you the ability to see
just how much power you are using and putting back in. Prevent those
energy checks!! ;-)
Most of the 12 Volt wiring in RVs is done using 12 or 14 ga. twinlead.
The most common seems to be white with a black trace to denote the
wire. When in doubt, check with a meter to determine which is positive
and which is ground. A lot of RVs also use a crimp style connector to
into these 12 volt wires to hook up lights and other low current
I don't personally care for these crimp connectors as they can fail
time, so any time I make a new connection, I use either wire nuts or
and heat shrink to make secure connections.
If you intend to install 12 Volt
equipment in your
RV, it's important to be sure that you use adequately sized wire to
the amperage requirements of whatever it is that you're installing.
a table of wire sizes and amperage ratings that will provide some basic
guidelines. This table leans a bit towards heavier wire than is
necessary, but that's actually safer in the long run. Always provide
protection of any new wiring that you install. The fuse should be sized
so as to protect the wiring from meltdown. Don't put a 20 amp fuse on a
circuit wired with 16 ga. wire.
Total Amperage Draw
Up to 4'
4' to 7'
7' to 10'
10' to 13'
13' to 16'
16' to 19'
19' to 22 '
22' to 28'
0 - 10
10 - 20
20 - 35
35 - 50
50 - 65
65 - 85
85 - 105
105 - 125
125 - 150
Last but not least, find your RVs 12 Volt Fuse Panel. It
could be anywhere.
Once you've found it, make a note of the type and sizes of fuses used
go get some spares. Many common fuses found in RVs can be purchased at
any automotive parts store. Spares, of the right sizes will come in
handy if you should blow a fuse down the road, and having the right
replacement fuse available will hopefully keep you from improvising a
replacement (bailing wire) or substituting a larger rated fuse than the
one that's blown (very similar to bailing wire!).
Most RVs use simple incandescent light fixtures. These work fairly
well, but draw quite a bit of current per bulb. The most common bulbs
are 1073 or 1141 automotive bulbs and they draw about 1.5 amps a piece.
Many RVs can benefit from the installation of additional lighting, to
brighten up dark areas or illuminate work areas. In some cases, the
light fixtures can be moved around or exchanged to provide lighting
better suits your needs. Incandescent fixtures are inexpensive and can
be found in any RV supply store or catalog. Although they are
when adding new lighting, it is worthwhile to consider alternatives to
those standard incandescent fixtures.
Fluorescent lights are excellent for
amounts of light for less current. Sunray and Thinlite
make high quality 12 Volt fluorescent lights in a variety of sizes and
configurations. These make great kitchen and workspace lighting. They
a little pricey, at $30 - $40 a piece, but work well and last a long
Avoid those really inexpensive fluorescent fixtures found in some
catalogs... they produce rather bluish light and tend to use up tubes
an alarming rate.
For more efficient use of power,
halogen lamps where possible. These fixtures deliver excellent white
for reading or detail work and use about 1/2 the power of standard
lamps. I'm particularly fond of the lamps that Sunnex offers. I have
near the bed for reading and one by my recliner. Sunnex has a web site
and an online catalog Stop by www.sunnex.com
for a look. These fixtures are a bit expensive, but well constructed
are flexible to allow them to be adjusted easily for best effect. Click
for a picture of a Sunnex lamp.
There are many 12 Volt appliances and accessories you can buy for your
RV. Some work very well and others are basically a waste of time. In my
experience, anything that uses resistance heating to accomplish it's
is a pretty sure bet to be a loser. A good example are the 12 Volt
pots you will see advertised in some RV catalogs. Trust me on this
they don't work. You will use up lots of battery power for very little
result. The main reason is that these items were designed to be used in
a vehicle with the motor running, so they are real energy wasters.
on things like 12 volt frying pans and 12 volt toaster ovens. Just
waste your money. On the other hand, there are a number of 12 Volt
that will actually improve your quality of life, whether you're plugged
into shore power or not. Here are a few of my personal favorites:
Definitely a great addition to any rig... a
"Fantastic Fan". This is
a high volume 12 Volt fan that replaces one of your existing roof
It draws very little current and can really help keep the rig cool
using the A/C. On low, it only draws a couple of amps and on high, it
exchange the air in your rig for cooler outside air in a minute or two.
Find them at any camping retailer... Try:
www.camperschoice.com www.campingworld.com Adohen
These are great little fans as well... they run on 12
volts and move
a lot of air for only about a 1.5 amp current draw. A couple of these,
strategically placed around your rig will keep you a lot cooler! Find
at camping stores or lots of automotive parts stores.
If you have some 12 Volt Cigarette lighter outlets
around your rig,
one of these small automotive map lights is a handy addition! I use one
to light my computer desk and it's great for providing light to type by
without a big battery drain. They are also handy to use as night lights
and can be removed and stowed when not needed.
Power saving suggestions for
All right... we've got our battery bank squared away, figured out our
charging sources, maybe installed an inverter and are all ready to
a week out in the wilds, far away from the RV park campers with their
hookups. Great! Here are a few tips on how to make life easier for you
and your own power company that's contained within your RV. The whole
to successful dry camping is conservation. I don't mean huddling around
a single flashlight to save battery power... I mean fully utilizing all
the functionality of your boondocking home without running out of
before you're ready to leave. Practice makes perfect, and as you get
to how your system works, you'll feel more confident being electrically
First off, start out with fully charged batteries.
Turn off lights when you don't need them.
Turn the radio off when you go outside.
Pay attention to those things that draw power and shut them down when
not actually using them.
Watch the battery meter and get a feel for how healthy your batteries
Refer to the tables from the 12
of Life part 1. If possible, recharge your
batteries before they
get down to 50% of capacity, as this will extend their life.
If you are using solar panels, pay attention to what's overhead. Park
rig so as to take the best advantage of the sun given where and how
panels are installed. In my case, with my installation, I try to set up
so that the rig is headed due south, especially in the winter.... that
takes advantage of the angle that my panel can be elevated on.
Take advantage of the current that your solar system generates during
day and run high current devices then... charge your laptop batteries
the inverter for later use, take showers and such , etc.
When operating on the inverter, beware of phantom loads!
possible scenario: You turn on the inverter to run your computer.
fine, but if your TV set and satellite receiver are still plugged in
last night, chances are they are still drawing power. This increases
amperage draw of the inverter and can run down your batteries much
My Satellite receiver draws exactly the same amount of power whether
on or "off". My 13" TV draws about 50 watts when it's on and about 12
when it's "off". Pretty sneaky, huh? One answer is to put inline
in the power cords of offending devices. Or, you can simply unplug them.
When you run your generator to charge your batteries, why not run an
heater too, if it's cold or the A/C if it's hot... you're running the
anyway, right? Or, conversely, if you run your genset for making coffee
every morning, your batteries will get a boost of charging right when
need it most... after a long hard night of supplying power for
If you like to dry camp in colder months, you are almost going to HAVE
to get a catalytic or radiant propane heater. That forced air furnace
comes standard in most rigs draws 5-7 amps whenever the blower's
That adds up in a hurry and will leave your batteries severely run down
after a couple of cold days. Plus, those furnaces barely approach 60%
meaning that a lot of your expensive propane is being used to heat the
great outdoors, instead of your rig. Check into a catalytic space
95% or better efficiency and no battery drain.
The bottom line....
Pay attention to your batteries. Maintenance and proper selection pay
in long life.
Provide for adequate charging and monitoring. Don't just "plug it in
Consider an inverter... they add a lot of convenience to your RV, even
if you don't dry camp all that much. Make an intelligent choice based
your needs and battery capacity.
Consider adding some solar charging capability to your rig. Do your
and remember: the best thing about solar is that it's modular. Buy some
now, expand the system later, you don't have to buy everything all at
A good monitor panel will make your life away from hookups much easier.
Plus, they're fun to play with! Whether you make your own or buy a
one, it will give you total control over your own power company.
If you choose to upgrade your RVs original equipment, or add new
follow good wiring practices. Just because it's only 12 volts doesn't
that you can do a half-assed job. Use proper wire, of the proper size
fuse new circuits to protect against overloads.
After all this work, take time enjoy the freedom that electrical
can bring. Explore some of those more remote spots. Spend some time at
Quartzsite or at the rallies and Escapades and never miss that
outlet! And most of all, don't ever let that 12 Volt electrical system
intimidate you again.... Knowledge is Power, and
with your knowledge,
you should have plenty of power, no matter where
Cat- 12V RV Battery part1
Credit- Mark S. Nemeth
RV 12V Circuits/Accessories II
Jan Watercraft Products, Since 2001 Thank you for visiting our site.
If you have any questions go to our "CONTACT
US" page and send us a e-mail or call!