Term
|
Definition
name the most perfect light source |
|
|
Term
most efficient, most pleasing to eye, most economical |
|
Definition
characteristics of daylight |
|
|
Term
position of sun in sky, weather (degree of cloudiness), natural and built obstructions |
|
Definition
what does the amount of light depend on? |
|
|
Term
cloudless, cloudless turbid, intermediate, overcast |
|
Definition
four basic models of luminance distribution |
|
|
Term
overcast, clear, partly cloudy |
|
Definition
|
|
Term
|
Definition
standard measurement for daylighting when all light is diffuse |
|
|
Term
|
Definition
brightness at top of skydone, less so at horizon |
|
|
Term
the illuminance at the horizontal and vertical planes |
|
Definition
what varies as solar altitude changes? |
|
|
Term
direct light from sun, diffuse light from sky dome |
|
Definition
what are the two sources in a clear sky? |
|
|
Term
total illumination for horizontal surfaces |
|
Definition
sum of direct and diffuse light and varies with solar altitude |
|
|
Term
total illumination for vertical surfaces |
|
Definition
sum of direct and diffuse light and varies with solar altitude and azimuth |
|
|
Term
|
Definition
impossible to predict due to the limitless variability of conditions |
|
|
Term
|
Definition
what produces more interior daylight than clear skylight? |
|
|
Term
Low cost, instant start and restart, inexpensive dimming, simple installation, cheap fixtures, good as point source, high power factor, full-spectrum color, great for skin tones |
|
Definition
advantages of incandescent lamps |
|
|
Term
low efficiency (14.8lm/W), short life, voltage sensitivity
Governments around the world have passed measures to prohibit sale |
|
Definition
disadvantages of incandescent lamps |
|
|
Term
|
Definition
tungsten filament inside glass filled, sealed bulb |
|
|
Term
|
Definition
light source with many different bulb and base sizes
coated inside with white silica for greater diffusion
most have screw bases, medium screw base most common |
|
|
Term
|
Definition
most common reflector lamps |
|
|
Term
|
Definition
most common reflector lamp |
|
|
Term
|
Definition
R for a reflector lamp means?
and PAR means?
|
|
|
Term
|
Definition
incandescent lamp filled with halogen gas and inside of a small quartz glass bulb (screw or pin connection) |
|
|
Term
longer life, lower lumen depreciation, smaller envelope, great as a point source |
|
Definition
advantages of tungsten-halogen lamps |
|
|
Term
still low efficacy, high temp, can explode (requires sheilding) |
|
Definition
disadvantages of tungsten-halogen lamps |
|
|
Term
|
Definition
flourescent high-intensity discharge lamps (mercury vapor, sodium and metal-halide) |
|
|
Term
|
Definition
provide high voltage to heat lamp filaments in pre-heat and rapid start circuits; strike arc through tube; limit lamp operating current |
|
|
Term
|
Definition
low bf = low operating cost, but produces less light; high bf = more energy use, more light, also means less fixtures, so in new construction this may be least costly
Ballast Efficiency Factor – ratio of bf to power (W) = lm/W |
|
|
Term
|
Definition
more expensive ballast but lower operating costs , smaller conductors, more fixtures per circuit |
|
|
Term
magnetic, hybrid, electronic |
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
magnetic transformer + electronic switch |
|
|
Term
|
Definition
ballast types that operate lamps at 20-60kHz = less power loss, high efficacy, lighter, more energy efficient, generate less heat, silent, can be dimmed |
|
|
Term
|
Definition
what can lower a ballast life? |
|
|
Term
|
Definition
how long do ballasts last? |
|
|
Term
RFI cause by arc discharge in tube |
|
Definition
what specifies RF noise suppressors and RF noise attenuators for fixtures themselves? |
|
|
Term
|
Definition
whats the most predominant lamp type in use? |
|
|
Term
|
Definition
sealed cylindrical tube with inert argon and low pressure mercury |
|
|
Term
|
Definition
what maintains the electric arc in flourescent lamps |
|
|
Term
|
Definition
what produces shore wave UV radation and excites phosphor coating on the inside of the tube emitting diffuse visible radiation? |
|
|
Term
|
Definition
what controls quantity and spectral quality |
|
|
Term
preheat flourescent lamps |
|
Definition
type of lamps found in existing buildings? |
|
|
Term
preheat gas and employ separate starter |
|
Definition
what do older flourescent lamps do as oppose to newer ones? |
|
|
Term
|
Definition
now a days what is the most common flourescent lamp starter? |
|
|
Term
|
Definition
which flourescent lamp uses a high voltage transformer? |
|
|
Term
|
Definition
what has half the life of the rapid-start lamp? |
|
|
Term
|
Definition
what lamp can opperate at really low temperatures? |
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
|
Definition
|
|
Term
compact flourescent lamps |
|
Definition
what can directly replace incandescents? |
|
|
Term
compact flourescent lamps |
|
Definition
folded fluourescent tubes with a built in ballast |
|
|
Term
|
Definition
what can a 60W incandescent lamp be replaced with? |
|
|
Term
life of 10-12,000 hours
saves $42 for life of lamp |
|
Definition
What is the life of a compact flourescent lamp and how much money can it save over 6hrs/day? |
|
|
Term
high intensity discharge lamp |
|
Definition
discharges electricity through high-pressure vapor inside bulb |
|
|
Term
high intensity discharge lamp |
|
Definition
has poor CRI, except metal-halide |
|
|
Term
in large areas that need high illuminance, energy efficiency and long life are required |
|
Definition
where would you use a high-intensity discharge lamp? |
|
|
Term
|
Definition
what has the best CRI up to 80-90? |
|
|
Term
|
Definition
Best CRI, up to 80-90
Various bulb types and sizes from 50-1500W
Efficacies of 75-105lm/W; last 10-20,000 hrs
Slow starting – 2-3minutes; restrike 8-10 mins
Hot-restrike ballasts provide instant restart, a must for indoor applications |
|
|
Term
|
Definition
why cant you dim a metal-halide lamp? |
|
|
Term
high pressure with high efficiancy up to 147 lm/W |
|
Definition
characteristic of sodium-vapor lamps |
|
|
Term
|
Definition
what efficiency does a low-pressure sodium vapor lamp have? |
|
|
Term
High efficacy, up to 147lm/W
Lowest CRI – 20-22, so don’t use where color rendition matters (yellow color)
High glare so shield or mount up high
Require ballast, slow to light, slower restrike w/out special ballasts |
|
Definition
characteristics of HPS sodium-vapor lamps |
|
|
Term
Highest efficacy, up to 150lm/W
Lowest CRI – 0, so don’t use where color rendition matters (yellow color)
Long life (+18,000 hrs), 100% lumen maintenance |
|
Definition
characteristics of low-pressure sodium vapor lamps |
|
|
Term
|
Definition
|
|
Term
Light-emitting Diodes (LED): |
|
Definition
has a long life, high energy efficiency, but initial costs are higher than those of flourescent |
|
|
Term
Light-emitting Diodes (LED): |
|
Definition
damaged by high temperatures, so they include heat sinks, cooling fins |
|
|
Term
|
Definition
why must led lamps include internal circuits to operate from standard AC voltage? |
|
|