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Some RVs simply have more
lighting than what is needed for the
rig. This may be too many halogen
puck lights, or it may be too many
fluorescent fixtures. Manufacturers
love to fill a rig with more than is
needed -- it looks impressive and it
increases the price. The result can
be either shining too much light into
the living space, or using too much
electrical power to create the
lighting, or both.
A prudent RVer will take a rational
approach to lighting. LED lighting
offers two ways to reduce the
lighting in an RV to a reasonable
level.
My situation is a typical example.
The fifth-wheel RV that I use at my
basecamp has sixteen 12-volt
fluorescent fixtures, each containing
two F15T8 tubes. Each fixture uses 30
watts (2.2 amps) of 12-volt power to
produce an effective 1,100 lumens of
white fluorescent light.
If all fixtures are turned ON at the
same time, the wattage is 480 watts
(40 amps), and that produces a rated
luminosity of 27,480 lumens. But
because of the limited light
efficiency of fluorescent fixtures,
the sixteen fluorescents only provide
an effective 17,600 lumens (1,100
lumens each).
Oh yes, since the electrical
efficiency of the ballast and lights
is only about 50%, they are pumping
240 of those watts into heating the
air in my rig. In my humble opinion,
that is just too much lighting (and
heating) for an RV, even a large one
with 400 sq-ft of space.
My sixteen fluorescent fixtures are
grouped into four sets of three each
and four singles. By turning OFF two
of the three fixtures in each group,
we could reduce our consumption to
240 watts (20 amps), and still have
an effective luminosity of 8,800
lumens. That helps, but the resultant
lighting is lumpy. It is too bright
in some areas and dim in other parts
of the rig. So we still have too much
lighting for some of the space we
live in, and too little
elsewhere.
The obvious solution is to switch to
LEDs to replace the fluorescent --
and that is what I did. But I did
more than simply replacing the
fluorescents with LEDs, I considered
the problem of having too much
light.
When I switched to LEDs, I
intentionally reduced the amount of
light from each fixture by
disconnecting the ballasts and
installing a single 12-inch length of
MyT.fLED LightStrip in each fixture.
Each fixture now provides an fully
effective 480 lumens of light,
pointing downward into the room, so
the total real lighting is 7,680
lumens, nearly what I gott by turning
off eight of the fluorescent
fixtures. And now the light is
constant throughout the rig, just as
we want it. At the same time I have
reduced the electrical load for
lighting from 480 to 96 watts, (40
amps to 8 amps).
As an added bonus, on warm summer
evenings, I no longer have to use
nearly 750 watts to power the air
conditioner to remove the excess heat
produced by the fluorescent fixtures
with their inefficiencies. That can
easily add up to an additional 3kwhr
per evening, so I am saving 4.2kwhr
per evening. When you live here in
southern California that is only
$0.90 per evening, but do that for
four months and it quickly adds
up.
At a retail cost of $37.20 each, the
cost of converting all sixteen
fluorescent fixtures is less than
$550 with the 10% quantity discount.
I get better light where I want it
without heat or fluorescent radio
interference or having to replace
fluorescent tubes. And it takes about
5 minutes to convert a fixture.
Using LEDs is a win-win
solution.
copyright
Sam Penny, August 15,
2011
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