The coiled coil arrangement
reduces filament cooling and increases the light output allowing the fil-
ament operate higher temperature. Thus, households will have use more energy-efficient lamps in
the future.
FIGURE 14.
Mr.
. fine tungsten wire first coiled and coiled again form
the incandescent filament the GLS lamp. One factor which may have contributed its popular-
ity that lamp designers have been able modify the glass envelope the
lamp give very pleasing decorative appearance, shown Fig.9
Some decorative GLS lamp shapes. Most the electricity goes producing heat and little pro-
ducing light.
GLS lamps
GLS lamps produce light result the heating effect electrical
current. The efficacy the GLS lamp lumens
per watt over its intended lifespan 1000h. The light output covers the vis-
ible spectrum, giving warm white yellow light with colour rendering
quality classified fairly good. 14.
The filament lamp its simplest form purely functional light source
which unchallenged the domestic market despite the manufacture of
more efficient lamps. The
Government calculates that every British household was replace three
60 100W light bulbs with CFLs, the energy saving would greater than
the power used the entire street lighting network.
Let now look four different types lamp.Basic Electrical Installation Work
288
produce more than lumens light output for every watt input. Hilary Benn, the Environment Secretary, has announced that the tradi-
tional GLS light bulbs 150, 100, and 40W will begin phased out
by 2010.9
