Home' Afloat : AFLOAT January 2016 Contents 60 AFLOAT.com.au January 2016
with Kurt Küpper*
* Kurt Küpper is director of Aquavolt
Electric Boat Parts. Tel: 02 9417 8455
So what else would you like to know? You are welcome to send in questions about
boat electrics or suggestions for topics that you would like explained.
LIGHT EMITTING DIODES
29E Babbage Rd, Roseville Chase 2069
Tel: 02 9417 8455
Fax 02 9417 8423
WHISPER QUIET FANS
While stocks last
3-speed white gimballed
fan with timer 12V
For full details see website
Everyone knows the benefits of LED
lighting compared to traditional
incandescent bulb based lighting.
It is well published that LED luminaires
are some 90% more efficient and also have
an up to 25 times longer life span. So the
decision to change from incandescent to
LED technology is an easy one. However,
comparing LED based lighting to halogen
lamps is like comparing apples and oranges.
With so many LED products on the
market how do you decide which ones to
If you are looking at upgrading or building
new with LED lighting there is usually a
substantial cost involved so you want to
make sure you select the best lamps for your
purpose and that they will provide the return
on investment. This means they should last
as long as promised and provide the light
performance desired. It is important to
compare apples with apples.
Important things to consider when
deciding to invest in LED lighting.
There are large differences of LED
luminaires in light performance for the
power consumed (lumens per watt). Unlike
traditional incandescent lamps or halogen
lamps where the amount of power a lamp
uses (wattage) is usually a pretty good
indication for how bright it will be.
The same applies to colour reproduction.
For halogen lamps this is quite consistent.
One LED lamp can be very different
from another. Lumens are a common
measurement used to describe the amount
of light a lamp produces.
This measurement is too often based
on the LED’s manufactured rating (Raw
Lumens). However this can be misleading
and not the actual measure of useful light
emitted by a LED lamp. Factors such as the
power used to drive the lamp, thermal losses
and optic and lens losses as light rays travel
through the lens all contribute to a possible
20-50% decrease of the light lumens emitted
by the LED. Good optic skills, circuit design
and material selection are required to
minimise internal lumen losses.
Lumen ratings can be misleading
because they refer to the total light emitted
from a luminaire, no matter whether this
emitted in a useful direction. Lux and candela
ratings refer to the actual light intensity from
the lamp at given distances and direction.
This way you know what light levels to expect
when designing your lighting layout.
Quality lighting manufacturers, using
state of the art photometric equipment, are
able to provide accurate lux or candela charts
so consumers get a fair representation of the
expected luminaire performance.
For accurate light performance, compare
If you stare directly into a LED luminaire,
chances are it will appear bright and dazzle
you. In fact looking directly at some of the
high power LED chips for extended periods
can be hazardous to the eye. The better optic
design shows an evenly bright surface of the
entire luminaire without any bright spots.
Well designed LED lamps use efficient
lens and optic designs to reduce glare and
eye strain while still projecting the light in
an evenly distributed pattern.
For example downlights will often have
a wide spread optic to fill a room and by
overlapping the wide spread beams from
several luminaires, shadows are much
reduced, whereas other lamps like spotlights
or courtesy lighting may be designed to focus
or direct the light in a specific direction to
achieve a specific effect.
Make sure you select a light with a lens
and optic design that reduces eye strain
and a light pattern to suit your location. h
• This is the first part of an article written by
Hellamarine and reproduced with the kind
permission of Hella Australia.
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