1
Q
Light is a special form of ________ which produces the sensation of sight
A
Electromagnetic radiation
2
Q
The wavelength of visible light ranges from approximately ________ to ________
A
380 to 760 nanometers
3
Q
A light source emitting radiant energy relatively balanced in all visible wavelengths will appear what colour?
A
White
4
Q
By passing a beam of white light through a prism, the beam will spread and separate into individual visible wavelengths known as a ________
A
Colour spectrum
5
Q
The ________ is a band of colours ranging from violet through blue, green, yellow, orange to red
A
Colour Spectrum
6
Q
The human eye is not equally sensitive to all colours (wavelengths), and tests have shown that the average eye is most
responsive to a wavelength of about ________ nanometers
A
555 nanometers (yellow-green)
7
Q
Name the four fundamental factors governing the visibility of a task
A
Size, brightness, contrast, and time
8
Q
The quantity of light output from a source is called ________, and it defines the time rate flow of light
A
Luminous flux
9
Q
The unit for luminous flux is the ________
A
Lumen (Lm)
10
Q
The density of light flux measured on a surface is known as
________
A
Illumination, or more simply as luminous flux density
11
Q
The unit for illumination is the ________
A
Lux (Lx)
12
Q
A ________ is a device that measures illumination
A
Photometer
13
Q
The two fundamental equations dealing with lighting calculations are the ________ and the ________
A
Inverse square law, cosine law of incidence
14
Q
An adequate quantity of light does not always provide good illumination. What three factors contribute to light quality?
A
Glare, colour, and diffusion
15
Q
________ is a level of brightness that causes interference with vision that typically causes discomfort or eye fatigue
A
Glare
16
Q
Name the three methods used to correct for glare
A
Decreasing the level of illumination by shielding the light source, decreasing the contrast between the source and its surroundings by using light colours on ceilings and walls, and/or repositioning the light source
17
Q
________ is the effect of scattering the light into many different directions
A
Diffusion
18
Q
What are three ways to achieve diffused light?
A
Using indirect light sources, utilizing large-area and low-brightness luminaires, and/or using a variety of different light sources
19
Q
Color has certain psychological effects on people and their emotions. ________ seem to produce a cool effect and create an illusion of increased space
A
Blues and greens
20
Q
Colour has certain psychological effects on people and their emotions. Which colours do people commonly associate with a feeling of warmth and coziness?
A
Reds, oranges and yellows
21
Q
Sources with ________ colour temperatures have “warm“ colour
(reddish or yellowish); while sources with ________ colour temperatures have “cool” colour (bluish)
A
Low (<3000°K), high (>4000°K)
22
Q
The ________ expresses the ability of a light source to portray the colour appearance of objects accurately when compared to a standard (reference) light source of the same colour temperature
A
Colour rendition index
23
Q
________ refers to how efficient a light source is at converting electrical energy into light, and includes all losses due to heat in the lamp, ballast, or control equipment.
A
Luminous efficacy
24
Q
At 100% efficiency 1 watt would produce ________ lumens
A
683
25
Incandescent lamps are the least efficient and produce only ________ on average
22 lumens/watt
26
Low Pressure Sodium are the most efficient and produce ________ on average
200 lumens/watt
27
Quality LEDs are substantially more efficient than incandescent lamps, but still fall short of low pressure sodium. Their average efficiency is ________
150 lumens/watt
28
________ put out light at all frequencies, including many infra-red wavelengths which we experience as heat, thus their inefficiency
Incandescent lamps
29
________ put out light in the ultra- violet part of the spectrum, that is then converted to visible light via the phosphor coating on the lamps
Gas discharge lamps (fluorescent)
30
________ lamps put out light only in the spectra of the elements inside them such as sodium, mercury or various halide salts. The selection of these chemicals is the basis of many lighting considerations including lamp life, strike up/re-strike time, efficacy, CRI, and ultimately cost
High intensity gas discharge (HID)
31
________ light sources are much more efficient than incandescent and concentrate production of light in the ranges that the human eye is most sensitive to while most of the losses occur in the lamps ballast and control circuit
Gas discharge
32
________ put out light in frequencies that combine to form white light with a high colour rendering index, making them a very efficient light source (150 Lm/W) with an excellent
CRI. The main losses occur in the conversion equipment. In the future it may be possible to achieve system luminous efficacy in the range of 200–250 Lm/W
LED's
33
A(n) ________ is a complete lighting unit consisting of lamps, wiring channel, reflectors, lens, diffusers, and control gear (such as ballasts for gas discharge lamps) where necessary
Luminaire
34
The purpose of the luminaire is to provide ________
The appropriate distribution of light
35
Name the three factors one should consider when selecting luminaire type
Luminaire efficiency, coefficient of utilization, and spacing-to-mounting height ratio
36
Luminaires provide light from five different types of sources. What are they?
Incandescent, fluorescent, high-intensity discharge (HID), low-pressure sodium, and LED
37
What are the two main causes of light loss (up to 50%) over time?
Lamp lumen depreciation, and luminaire dirt depreciation
38
True or false: the light bulb was invented by Thomas Edison
False. Edison perfected the design so that it could used more safely in homes, but the light bulb itself was invented in 1878 by Joseph Swan
39
Name the advantages and disadvantages of incandescent lamps
They're cheap, compact, and produce light with a warm tone. They're also extremely inefficient. 90-95% of their energy input is lost through heat
40
Incandescent lamps have filaments made of ________, which has a high melting point of ________ and a low rate of evaporation
Tungsten, 3419°C
41
Regarding incandescent lamps, increasing the operating temperature of the filament results in ________ light output and ________ life span of the bulb
Increased/higher, decreased/shorter
42
________ inside the incandescent bulb reduces the rate of filament evaporation
Inert gas, commonly Argon
43
What size and shape of bulb is designated G-57?
Globular shaped bulb, with a 7 1/8" base
44
What size and shape of bulb is designated T-10?
Tubular shaped bulb, with a 1 1/4" base
45
The code 'R' is given to which shaped bulb?
Reflector
46
What code letter(s) designate parabolic shaped bulbs?
PAR
47
The code 'PS' is given to which shaped bulb?
Pear shaped
48
What code letter(s) designate tubular shaped bulbs
T
49
The code 'F' is given to which shaped bulb?
Flame shaped
50
What code letter(s) designate straight side shaped bulbs?
S
51
True or false: the code letter 'S' is used to designate standard shaped bulbs
False. Standard shaped bulbs are designated the code letter 'A'
52
The code 'G' is given to which shaped bulb?
Globular
53
Name the three types of glass used in lamp bulbs
Clear, diffused, and coloured
54
The most commonly used base for a general service lamp is the ________
Screw type, or Edison base
55
Lamps with screw type bases come in 4 sizes. What are they?
Mogul, medium, intermediate, and candelabra
56
Low-wattage indicator lamps and decorative lights use either a ________ or ________ base
Intermediate, candelabra
57
Where accurate filament positioning is required, ________ or ________ bases are preferred
Prefocus, bayonet
58
True or false: high-wattage lamps have a lower efficacy (lumen output per watt) than low-wattage lamps of the same voltage
False. High-wattage lamps are more efficient have a higher efficacy than low-wattage lamps of the same voltage
59
True or false: one 150W lamp produces more light than three 50W lamps
True
60
________ filament temperatures produce greater efficacy, but have a ________ service life
Higher, shorter
61
True or false: compared to 120V lamps, low voltage lamps normally have a shorter service life
False
62
How many hours are traffic signal lamps commonly rated for?
6000 hours
63
How many hours are general service 120V lamps rated for?
750 to 1000 hours
64
Which lamps are not designed to be used in more than one burning position?
Projection, spotlight and floodlight lamps
65
Describe the effect of over-voltage and under-voltage operation on a light bulb?
Over-voltage results in a brighter light, but shortens the lifespan of the bulb. Under-voltage yields a dimmer light, but increases the lifespan of the bulb
66
General service lamps may be burned in any position, but are most effective when operated with the base ________
Pointing up (ie, on a ceiling with the light pointing downwards)
67
During the operation of an incandescent lamp, the filament steadily ________, causing a slow but continuous reduction in light output
Evaporates
68
To slow the rate of filament evaporation, lamps of 40 W and higher are filled with ________
Inert gas
69
The ________ is a special type of incandescent lamp
Tungsten-halogen lamp
70
The tungsten-halogen lamp is also called a ________ lamp or a ________ lamp
Quartz-halogen, quartz-iodine
71
In addition to the gases normally found in filament lamps, the tungsten-halogen lamp has a small quantity of ________
Halogen gas (iodine or bromine)
72
When a tungsten halogen filament burns it slowly evaporates, just like a standard incandescent lamp, but the additional halogen gas combines with the evaporated tungsten and redeposits it back onto the filament. This is known as its ________
Regeneration cycle
73
Due to its high bulb-wall operating temperature, quartz glass with a melting temperature of ________ is used in tungsten-halogen lamps
1650°C
74
Due to its compact construction, the tungsten-halogen lamp is often combined with a ________ shaped reflector, or placed in a suitable luminaire having its own reflector
Parabolic
75
In case the lamp shatters during operation, the tungsten-halogen lamp must be placed within a ________
Glass envelope
76
Why is it not advised to operate tungsten-halogen lamps at a reduced voltage?
Dimming of tungsten-halogen lamps may interfere with the regenerative cycle, which relies on the outer wall of the quartz to reach 250°C or higher
77
Why must gloves or careful handling be used when handling tungsten-halogen lamps?
Oils present on our skin can be deposited onto the glass. When heated, these oils cause the glass to blister and can lead to the premature failure of the bulb
78
What are the three main types of devices used to control incandescent lighting?
Snap switches, dimmer switches, and relays and contactors
79
What are the three most common types of snap switches?
Single-pole switch, three-way
switch, and the four-way switch
80
________ are used to control a light from two locations
Three-way switches
81
________ are used when a lamp (or a number of lamps) are to be controlled from three or more locations
Four-way switches
82
________ switches are activated by pulling on a cord or chain
Pull type
83
The most common type of dimmer switch is the ________, which mounts in a standard switch box
Rotary type
84
Which lamp types are not compatible with incandescent dimming switches?
Fluorescent and other types of gas-discharge lamps
85
With low-voltage relay control, relays located in the lamp outlet boxes perform the actual switching. The relays are controlled by ________ switches operating on ________
Rocker-type, 24 or 30V
86
What are the main advantages of low-voltage relay controls?
Low voltage at the switches enhances safety, wiring to these switches can be inexpensive bell wire, and additional switches can easily be connected, allowing the lamp to be controlled from several different locations
87
A ________ is used in situations where a large bank of lights is required to come on at the same time
Lighting contactor
88
True or false: unlike a motor starter, a lighting contactor does not require overload heaters in the power circuit or overload contacts in the control circuit
True
89
A(n) ________ is an electro-chemical light source
LED (light-emitting diode)
90
The efficacy of LED sources is improving continuously; for white LEDs, efficacy currently ranges from about ________ lumens per watt, depending on the manufacture
75 to 150
91
________ in a light source is the gradual reduction in light output over time, caused by normal deterioration of phosphors, cathodes, filaments and the other components of the system
Lamp lumen depreciation
92
What type of light is produced by a two-stage process?
Fluorescent light
93
Describe the two-stage process that fluorescent lights use to produce light
First, electric current passes through a gas inside a glass tube and produces invisible ultraviolet (UV) radiation. The UV radiation is converted to visible light at the glass by a layer of phosphor powder which coats the inside surface of the fluorescent lamp
94
A ________ is needed for all types of fluorescent lamps
Ballast
95
What are the two functions that a ballast performs?
It provides the high starting voltage necessary to ignite the tube, and it limits the current in the tube once it lights
96
As a rule, the longer and more narrow the arc tube, the ________ the necessary striking voltage
Higher
97
True or false: a 4’ T12 will require a lower striking voltage than a 4’ T8 tube of the same wattage rating
True. Although both tubes are the same length, the T12 is wider than the T8 and requires a lower starting voltage
98
Fluorescent lamp fixtures come in three classifications. What are they and when were they first developed?
The preheat start - first used in the 1930s; the instant-start - developed in the 1940s; the rapid-start - developed in the 1950s
99
In an ________ fixture, the ballast houses an autotransformer which steps up the supply voltage to a magnitude sufficient to strike an arc between the two ends of the tube
Instant-start
100
Fluorescent instant-start fixtures light instantly the switch is closed. What is the term for this process? What are the drawbacks?
Cold-cathode starting. Cold-cathode starting tends to reduce the lamp service life due to the high starting voltage, and can present a safety hazard as these types of circuits can produce 400 to 800V
101
Compared to the instant-start, what 3 shortcomings does the rapid-start eliminate?
The high striking voltage needed for cold cathode starting poses a safety concern, plus it results in shortened lamp life. The need for large, heavy ballasts is also eliminated
102
________ replace the standard core and coil ballasts with solid-state electronic circuitry
Electronic ballast - ELVs Electronic Low Voltage
103
Name the advantages and disadvantages of electronic ballasts
Advantages: they have a cooler operating temperature and are quieter. Disadvantages: high cost, high failure rate compared to core and coil ballasts, they generate significant amounts of power line harmonics and electromagnetic radiation, and some electronic ballasts use voltages similar to cold-cathode starting, meaning they pose a danger and reduce overall lamp life
104
For some ballasts, many fluorescent fixtures work at supply voltages of ________ or higher
347V
105
Approved lighting contactors have the words ________ printed on them
“For continuous operation at 100% of rating”
106
Sometimes fluorescent fixtures are approved for end-to-end assembly. For these installations, the voltage rating of the wiring must be not less than ________, and the temperature rating must be not less than ________
600V, 90°C
107
Many older ballasts are filled with oil and older ballasts may contain ________ which are a health hazard
PCBs
108
Ballast ________ is one of the prime causes of failure. A 10°C rise in ambient temperature will reduce the life of a ballast by ________
Overheating, half
109
Name the three bases most often used with fluorescent lamps
Bipin, single pin, and recessed double-contact bases
110
The rated life for most fluorescent lamps is in the ________ hour range
7500-20,000
111
The instant-start type lamps tend to be at the _________ end of the rated life range and rapid-start lamps tend to be at the ________ end
Lower, higher
112
Fluorescent lamp life is reduced by which 4 common reasons
Switching too frequently, operating with the wrong type of ballast, using excessive supply voltage, and losing cathode pre-heat during start-up
113
________ refers to tubes needing to be run for 100 hours to establish
smooth, non-flickering operation
Seasoning
114
Special ________ may be required to start a fluorescent lamp if the ambient temperature is too low
Cold weather ballasts
115
A ballast should last _________ years under normal operation
12-15
116
A ballast with an ________ rating is quietest and a ballast with an _______ rating is noisiest
A, F
117
Standard rapid-start lamps, which operate at ________ mA, are the most common type of fluorescent lam
430mA
118
High output lamps operate at ________ mA and are called “HO”. Very high output lamps operate at ________ mA and are called “VHO” or “SHO” for super high output
800mA, 1500mA
119
________ use a phosphor that radiates UV in the 350 nm wavelength range which
is invisible to the human eye
Blacklights
120
Special energy efficient fluorescent lamps are designed for use with standard ballasts and operate at wattage reductions of ________
10-20%
121
Rapid fluctuations of light can cause a ________ in which moving objects are seen in repetitive flashes at successive positions
Stroboscopic effect
122
The ________ is the most efficient lamp source presently available
Low-pressure sodium (LPS) lamp
123
The typical efficacy of induction lamps is ________ lumens per watt
65-70
124
The long lifetime of the induction lighting system is due to the fact there are no ________ as in conventional lamps
Filaments or electrodes
125
Induction lamps have a lifespan of ________
100,000 hours, 25 years
126
True or false: Low-pressure sodium lamps like fluorescent lamps, require a ballast to provide a high striking voltage for starting
True
127
A LPS lamp typically takes ________ for it to reach its full light output
7-10 minutes
128
True or false: the LPS lamp restarts almost instantly after a short power outage
True
129
The average life of an LPS lamp is rated at ________
18,000 hours
130
Fluorescent, low-pressure sodium lamps, and high-intensity discharge (HID) lamps are all ________ in which light is produced by passing electric current through a gas
Gas discharge lamps
131
How long does it take for a Mercury Vapour lamp to reach its full light output?
3-7 minutes
132
The re-strike time for Mercury Vapour lamps is typically between ________ minutes
4-6
133
Efficacy of mercury vapor lamps is in the ________ lumens/watt range, with the higher ratings for lamps with higher wattage
30-65
134
Mercury vapour lamps have a rated life of ________
24,000 hours
135
Compared to mercury vapour lamp, the metal-halide lamp usually has a ________ starting voltage with an equivalent wattage
Higher
136
The start-up time for a Metal Halide lamp is typically ________
5-7 minutes
137
True or false: because the arc tube of the metal halide lamp operates at a higher temperature than the mercury lamp, it requires a longer cooling period before re-striking
True
138
Metal halide lamps can take as long as ________ to re-strike
15 minutes
139
True or false: The efficacy of metal halide lamps is much higher than mercury lamps, but the rated average life is shorter
True
140
A metal-halide lamp lasts about ________
15,000 hours
141
Although the operation of high-pressure sodium (HPS) lamps is similar to mercury and metal halide lamps, they are much different in other respects. Name their differences
No starting electrode, special circuitry in the ballast that provides an initial high voltage spike of 2,500 volts or more, and an arc tube that contains xenon gas and a small amount of sodium mercury amalgam
142
The HPS lamp comes to full brilliance in ________
3-4 minutes
143
An HPS lamp typically takes ________ to re-strike
Less than 1 minute
144
HPS lights typically provide ________ lumens/watt and have a rated life of ________
140, 24,000 hours
145
Mercury vapor bulbs are available in
sizes ranging from ________
40-1000W
146
Metal-halide lamps are available in sizes ranging from ________
175-1500W
147
HPS lamps are available in sizes ranging from ________
35-1000W
148
What do the letter codes, 'B', 'BT', 'E', 'PAR', and 'T' signify?
Bulged, bulged tubular, elliptical, parabolic aluminized reflector, and Tubular
149
Define each of the following burning position codes: 'U', 'H', 'BU', 'BD', 'HBU', 'HBD', 'VBU', and 'VBD'
Universal, Horizontal ONLY, Base up, Base down, Horizontal to base up, Horizontal to base down, Vertical to base up, and Vertical to base down
150
What does the ANSI code H36BT–1000/DX designate?
H - Mercury Vapour
36 - Ballast type
BT - Lamp shape bulged tubular
1000 - watts
DX - deluxe white phosphor coated
151
What does the ANSI code M36E–1000/WDX designate?
M - Metal Halide
36 - Ballast type
E - Elliptical shape
1000 - watts
WDX - Warm white phosphor coated
152
What does the ANSI code S56PAR–1000/WDX designate?
S - HPS
56 - Ballast type
PAR - Parabolic aluminized reflector
1000 - watts
WDX - Warm white phosphor coated
Level 2
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