1. Lighting Systems: Electrical Sources Chapter 3 © 2006 Fairchild Publications, Inc.

2. Bubble diagrams anyone?

3. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 3 Lamps Incandescent Tungsten-halogen Fluorescent HID (High-Intensity Discharge) –Mercury vapor –Metal halide –High-pressure sodium

4. Lamps

5. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 5 Specialty Remote source illumination systems: –Fiber optics Neon lamps Electroluminescent lamps: –LEDs (Light-emitting diodes)

6. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 6 Lamp Characteristics Light output Efficacy Color Lamp life Maintenance factors Cost

7. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 7 Lamp Characteristics A lamp’s light output is measured in lumens A footcandle: –Amount of light that falls on a surface in a one-foot radius from the source –Measurement is the lamp’s lumen per square foot

8. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 8 Lamp Characteristics A footcandle is the amount of light that falls on a surface in a one-foot radius from the source.

9. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 9 Lamp Characteristics Candlepower measurement: –A lamp’s candela describes the intensity of a light source in a specific direction Wattage: –Amount of electricity consumed by a lamp Efficacy: –Energy efficiency of a lamp –Lumens per watts (LPW) consumed

10. Comparative lamp efficacy

11. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 11 Lamp Characteristics Chromaticity or color temperature: –Degree of red or blue of a light source –Measured by kelvins (K) –A warmer apparent color of a light source will have a lower number

12. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 12 Lamp Characteristics Color-rendering index (CRI): –Measures how well a light source makes objects appear –Index range is 0 to100 –The higher the CRI number the better the color rendering ability of the lamp

13. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 13 Lamp Characteristics Lamp life: –Calculation derived by recording how long it took for ~ 50% of a large group of lamps to burn out Replacement considerations: –Lamp life and deterioration –Initial cost of the lamp

14. Lamp life

15. Consider heat load on building too…

16. Comparison chart for all source types

17. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 17 Lamp Characteristics Maintenance considerations: –Location of installation –Energy requirements –Location of lamps and labor

18. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 18 Incandescent Lamps Operating principles: –An electrical current heats the tungsten filament until incandescence is reached –Heat causes filament to thin and eventually break –Fragments of tungsten deposit on glass of the bulb Basic components of an incandescent lamp are shown in Figure 3.3 on page 64 of your text.

19. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 19 Incandescent Lamps Bulb made of blown soda lime (soft) glass Inert gases added to bulb to reduce oxidization of tungsten filament: –Standard lamp has argon with some nitrogen –Halogen improves performance by redistributing oxidizing tungsten on the filament

20. Standard incandescent lamps shapes and their designations

21. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 21 Incandescent Lamps Three-way lamps have two filaments: –One filament for lowest wattage (50) –Second filament produces next highest wattage (100) –Two filaments operating together produce highest illumination wattage level (150)

22. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 22 Incandescent Lamps 10–15% of the energy produces light Dimming reduces amount of light and heat Affects workload of air conditioning systems Operating volts of a system affect its life Horizontal or vertical positions

23. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 23 Incandescent Lamps Advantages: –Provide the greatest amount of flexibility –Directional or non-directional illumination –Varied size and shape –Easy dimming –Quick on –Frequent starts –Optical control –Low initial cost –Excellent color rendition and chromaticity

24. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 24 Incandescent Lamps Disadvantages: –Low efficacy rating –Generation of heat –Relatively short life –Damages artwork, fabrics, and other precious materials

25. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 25 Incandescent Lamps Codes developed by ANSI: –A letter describes the shape of the lamp –Letter followed by a number indicates diameter of the lamp in 1/8 inches –Example: A19 - “A” is code for an “arbitrary” shape Lamp is 2 3/8 ” (19/8) wide at widest point on bulb

26. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 26 Incandescent Lamps Variety of types: –Clear, frosted, soft-white, crown-silvered, colors, and protective coatings –Frosted lamps: Acid etch –Soft-white lamps: Coated with silica –Crown-silvered lamps: Coating covering top half –Most common colors are red, blue, yellow, and green –Rough service –Protective shielding

27. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 27 Incandescent Lamps Reflector (R) lamp: –Improves efficacy and directional qualities Halogen parabolic aluminized reflector (PAR) Elliptical reflector (ER) Multifaceted reflector (MR) Indoors: R, ER, MR Outdoors: PAR Cool-beam PAR

28. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 28 Incandescent Lamps Reflector beam spreads ranges: spot to flood Codes: –SP, NS, VNSP, WFL, MWFL, VWFL Example: –SP10: a spot lamp with a 10% beam distribution

29. Reflector (R) and Parabolic Aluminized Reflector (PAR) Lamps

30. Efficiency of the reflector

32. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 32 Tungsten-Halogen Lamps Halogen regenerative cycle: –Evaporated tungsten redeposit on the filament –Requires a heat-resistant glass (quartz) ~ 20-30% more efficient than incandescent Longer life Whiter light Higher color temperature and efficacy rating MR 16, MR11 MR8, and PAR popular

33. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 33 Tungsten-Halogen Lamps Line voltage in US is 110 standard volts Low-voltage between 6-75 volts Transformer: –Device to step down electrical current Luminaires with multiple fixtures cannot exceed maximum wattage of the transformer

34. The halogen “cleaning cycle”

35. Different lamps come with different bases: can help (or hurt) inventory control

36. Halogen incandescent lamps shapes and their designations

37. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 37 When is the best time to use those highly inefficient incandescent lamps?

38. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 38 Discharge Lamps Operating principles: –Electrical current passes through hot tungsten cathodes at end of tube –Tube with low-pressure mercury vapor gas and other inert gases –Cathodes emit electrons that excite mercury gas –Vaporized mercury produces radiant energy, mostly invisible ultraviolet rays

39. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 39 Discharge Lamps Operating principles: –Phosphorous coating on inside of tube re- radiates ultraviolet rays to visible spectrum –As visible light is produced, phosphor coating fluoresces –Glow occurs at a very low temperature –Phosphorous coating determines color of the light

40. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 40 Discharge Lamps General characteristics: –Do not have filaments –Operate on low or high pressure –Mercury or sodium gases –Maintains a fairly consistent color –Require a ballast to start lamp and control electrical current

41. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 41 Ballasts Operating life of ballasts: ~ 3 times a fluorescent lamp Magnetic and electronic versions Electronic ballast preferred: –More energy efficient –Quieter –Weighs less than magnetic ballast a. A ballast with a separate control gear b. A ballast built into the unit

42. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 42 Fluorescent Lamps Initial fluorescent lamps: Halophosphate (limited range of colors) Triphosphors made from rare- earth (RE) phosphors: –Improved color properties –Better efficacy ratings

43. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 43 Fluorescent Lamps RE-70 fluorescent: –Thin coat of conventional phosphors and triphosphors –7 represents the CRI range between 70-79 Coding example: RE-730 –7 represents CRI range between 70-79 –30 is temperature of 3000 – 3099K

44. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 44 Fluorescent Lamps 3 types of lamp-ballast circuits: –Preheat: Heats cathodes at start of illumination Used for lower wattage lamps Button held down to start –Instant start: No starter High open circuit voltage: Slightly reduces life of lamp

45. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 45 Fluorescent Lamps Rapid start: –Operates by continuously heating cathodes –Most common system used today –Can illuminate lamps at high wattages –Longer life than other two types –Dimming can only be done with a rapid start system

46. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 46 Fluorescent Lamps Most common lamps are the straight tubes: –T12, T8, and T5 Nomenclature for F48T12CW: –Fluorescent (F) lamp –48 watts (48) –Tubular shape (T) –12/8 ” in diameter (12) –Cool-white color (CW)

47. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 47 Fluorescent Lamps Shapes: Straight tubular, U-shape, and circle High cost of triphosphors coatings led to lamps in smaller diameters T8 has been successful: –Improved efficiency –Enhanced color –Small 1” diameter –Lamps physically interchangeable with T12 –T8 and T12 use different ballasts

48. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 48 Fluorescent Lamps T8 characteristics: –LPW is ~ 25% better than T12 lamp –Increasingly more popular –Will eventually eliminate T12 lamps T5 characteristics: –Smaller and slightly more efficient than T8 –Poses retrofit problems –Only available in metric sizes –Mini-bipin base is restrictive

49. Parts of a fluorescent lamp

50. Fluorescent lamp shapes and data

51. Fluorescent lamp bases

52. Ballast construction Can effect efficacy of luminaire Generally considered hazardous waste

53. Where are they?

54. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 54 Fluorescent Lamps Advantages: –Energy efficient –High lumen output –Long life –Radiate less heat than incandescent –Moderate initial cost –Low operating cost –Variety of color options –Use up to 80% less energy than incandescent –Can last up to 18 times longer than incandescent

55. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 55 Fluorescent Lamps Disadvantages: –Needs a ballast –Flickering can occur –Indoor use only –Time needed to reach maximum lumen output –Sensitive to ambient temperatures –Dimming is expensive –Shape and size limitations –Mismatches with lamps and ballasts –Variations between lamp manufacturers –Continuous on and off is detrimental to life and performance of lamp

56. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 56 Compact Fluorescent Lamp (CFL) To create the CFL, 1 or 2 linear fluorescent tubes are folded Available in twin, triple, and quad tubes Ballast: –Separate control gear or –Built into the unit (integral system)

57. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 57 Compact Fluorescent Lamp (CFL) Characteristics: –Produces a high lumen output –Up to 75% energy savings compared to incandescent –Some local building codes require in commercial interiors –Some not designed to be dimmed

58. Compact fluorescent family

59. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 59 Do you have fluorescent lamps in your dorm rooms? Do you like them?

60. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 60 High-Intensity Discharge (HID) Mercury vapor (MV)  Metal halide (MH)  High-pressure sodium (HPS)

61. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 61 High-Intensity Discharge (HID) Mercury Vapor lamps developed in 1901: –Used on a regular basis by 1930s –MH and HPS lamps developed in 1960s

62. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 62 HID Functions Similar to fluorescent lamp: –Illumination begins with an arc between 2 electrodes –Operates in a gas-filled cylindrical tube –Requires ballasts –Creates radiant energy from gases and metal vapors Don’t use phosphors to generate light in visible range

63. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 63 HID Functions Names of HID lamps indicate the primary gas that is ionized: –MV lamps is mercury –MH lamps have chemical compounds of metal halides and possibly vapors of metals such as mercury –HPS utilizes sodium

64. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 64 HID Lamps HID ballasts (auxiliary controls) made for specific lamp types and wattages Electronic ballasts are the best choice for HID lamps: –More efficient than magnetic ballasts –Can best control voltages: Results in longer life More consistent color over life of lamp Requires a ballast designed for dimming

65. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 65 HID Lamps Primary shapes: –A, B, BT, E, ED, T, and directional PAR and R Nomenclature: –Letter for MV is “H” (stands for Greek word for mercury) –Letter for MH is “M” –HPS letter is “S” –Following letter is generally the wattage

66. HID Lamp construction

67. Metal Halide Lamp shapes

68. Restrike time

69. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 69 Advantages – HID Lamps HID characteristics: –High efficacy –Long life –High LPW performance –Operation in a wide range of ambient temperatures –Positive long-term economics

70. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 70 Advantages – HID Lamps MH lamps: –High efficacy –Good color rendition –Long life –Good lumen maintenance –Wide spectrum of colors and wattages –Available in the incandescent lamp shape –Warm and cool color renditions –Excellent optical control –Operate in a variety of temperatures

71. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 71 Advantages – HID Lamps HPS: –Extremely high LPW rating –Exceptionally long service –Excellent long-term economics –Can last 40,000+ hours –Over-wattage can shorten life of lamps –Compared to other HID lamps, HPS lamps most adversely affected by frequent starts –Designed to operate over long periods of time –Seasoning required to reach full operating capacity

72. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 72 Disadvantages – HID Lamps Requires start-up time Color shifts during the life of lamp Variations in color between the same lamps Strict ballast requirements Not easily dimmable

73. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 73 Disadvantages – HID Lamps Start-up times between 2-10 minutes Restrike time up to 15 minutes: –Lamp must cool down before starting again –Problematic for safety and security Restrike occurs: –Power interruption –Insufficient voltage in the system

74. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 74 Disadvantages – HID Lamps Some instant restrike lamps: –Available only at high wattages –Must be used with special luminaires and ballasts –Specify an additional luminaire during restrike time –Specify a lamp with an auxiliary unit built into lamp –Due to warm-up and restrike, not advisable for use with motion detectors

75. Lighting and HVAC

76. Chilled beams

77. Multi-service chilled beam

81. Chapter 3 Electrical Sources © 2006 Fairchild Publications, Inc. 81 Homework Go through each programmed space in our project, and note which light might be the best balance between efficiency and quality