Module 4, Lesson 1 Flashcards
Define a light source
Any device that produces light
Light bulbs are technically called
Lamps
Lamps are what in a circuit
Loads
illumination produced by a lamp can be measured in
Light emitted and the amount reaching a surface
3 light measurements
Lumen, candela, and footcandle
Candela characteristics
Common called “candle power” but that’s incorrect, measured as the luminous intensity in a given direction, and a wax candle has the power of 1 candela
footcandle characteristics
The measurement of “luminous flux” or the illuminance that falls on a surface, the illuminance is one square foot distributed uniformly, and one foot away from one source of a candela and illuminance appears on a surface
Lumen characteristics
Measurement of “luminous flux” or unit of measurement emitted by a light source and one lumen is equal to the light striking a one square foot area
The most widely used term to used to rate light output
Lumen
Light outputs are measured in what
Wattage
Inverse square law
The illuminance “falls off” as the distance from the light source increases
2 light loss factors
Lamp lumen depreciation and dirt depreciation
Fixtures are often called
Luminaries
Luminaire functions
Provide physical support for the lamp, supply and regulate power to the lamp, and controls light distribution
Light source characteristics
System voltage, wattage, hours of life, and lumens of light output
