*Lighting & Electrical Systems Flashcards
What are direct lighting systems?
provide 90%-100% of the light output on the task
What are semidirect lighting systems?
provide 60%-90% of the light down and from 10%-40% toward the ceiling
What is direct-indirect lighting system?
provide equal amounts of light up and down
What is general diffuse lighting system?
all sides. light diffuses into room
What is semi-indirect lighting system?
most of the light toward to ceiling some down
What is a indirect lighting system?
throw from 90%-100% of all light toward the ceiling
What types of bulbs are incandescent?
halogen and xenon
What types of bulbs are discharge?
fluorescents and HIDs
What types of bulbs are Soild State?
LEDs
Define efficacy
A measure of energy efficiency.
Lumens per watt (similar to miles per gallon)
What are Xenon bulbs are what are their characteristics?
- Incandescent
-Xenon gas with warm light
-Dimmable but not energy efficient because they give off more heat
What are halogens and what are their characteristics?
- Bright but hot
- Cheap up front, but cost more to operate and have a short lamp life
-Dimmable
What are fluorescent and what are their characteristics?
-more energy-efficient because they give off minimal heat
- have a harsh white color
- not dimmable without special housing and switching
What are LED bulbs and their characteristics?
- Light-emitting diodes
- long-lasting
- Have lower heat and energy use
- lower operating cost but more expensive up front
- require a low voltage dimmer
What are High-Intensity Discharge (HID) bulbs and their characteristics?
- includes mercury vapor, metal halide, ceramic metal halide, and high pressure sodium lamps
- Pass an electrical current through gas containing metal vapors. This produces an arc of light
Low voltage lighting includes…
incandescent lamps and LEDs
Define candlepower
unit of luminous intensity approximately equal to the horizontal light output from an ordinary wax candle (candela)
Define lumen
Which type of lights can be switched together?
A) LED and halogen
B) LED and fluorescent
C) LED and xenon
D) none of these can be switched together
D) none of these can be switched together
Because different lamp types are used for different purposes, it is not always desirable to switch them together, even when you can. Lights on a dimmer should also be on a separate switch.
Which of the following should not be a primary consideration when choosing a light source?
A) aesthetics
B) color rendition
C) efficacy
D) operating life cost
A) Aesthetics
When selecting lighting fixtures, which brightness ratio is considered acceptable in a commercial office space between the task and general surroundings?
5:1
Which of the following sources would be most appropriate for the warehouse portion of a large furniture dealership?
A) cool-white deluxe fluorescent
B) mercury-vapor
C) high-pressure sodium
D) metal-halide
D) Metal-halide
they have a high efficacy (80 lm/W to 120lm/W) and good color rendition. You’ll often see them used in warehouse-style retail stores like Home Depot and Costco.
What are the important considerations of light quality?
glare,
contrast,
uniformity and
color.
Where is the junction box for a power pole located?
plenum
Which of the following sources would be most appropriate for the warehouse portion of a large furniture dealership?
metal-halide
they have a high efficacy (80 lm/W to 120lm/W) and good color rendition.
The designer is working on an office project where company employees are intense computer users (approximately 6-8 hours daily).
Which type of lighting would be most appropriate for this setting?
direct - indirect lighting
distribute light up and down about equally. Indirect systems direct all the light toward a reflective ceiling, where the light illuminates the room by reflection.
