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WHAT IS A LUMINAIRE? NEC defines a luminaire as a complete lighting unit consisting of a light source such as lamp or lamps, together with the parts designed to position the light source and connect it to the power supply. * Luminaire is the international term for "lighting fixture" and is used throughout the NEC. TYPES OF LUMINAIRES There are literally thousands of different types of luminaries from which to choose to satisfy certain needs, wants, desires, space requirements, and, last but not least, price considerations. Note in Table 1 that whether the luminaire is incandescent or fluorescent, the basic categories are surface mounted, recessed mounted, and suspended ceiling mounted. === Table 1 === Mountings for basic categories of luminaires. Fluorescent • Incandescent • Surface • Surface • Recessed • Recessed • Suspended Ceiling • Suspended Ceiling === The Code Requirements Article 410 sets forth the requirements for installing luminaires. The electrician must "meet Code" with regard to mounting, supporting, grounding, live-parts exposure, insulation clearances, sup ply conductor types, maximum lamp wattages, and so forth. Probably the two biggest contributing factors to fires caused by luminaries are installing lamp wattages that exceed that for which the luminaire has been designed, and burying recessed luminaries under thermal insulation when the luminaire has not been designed for such an installation. Nationally Recognized Testing Laboratories (NRTL) tests, lists, and labels luminaires that are in conformance with the applicable UL safety standards. Always install luminaires that bear the label from a qualified NRTL. In addition to the NEC, the UL Electrical Construction Materials Directory (Green Book) and the UL Guide Information for Electrical Equipment (White Book), and manufacturers' catalogs and literature are excellent sources of information about luminaires. Read the Label NEC 110.3(B) states that Listed or labeled equipment shall be installed and used in accordance with any instructions included in the listing or labeling.* It is important to carefully read the label and any instructions furnished with a luminaire. Most Code requirements can be met by simply following this information. Here are a few examples of label and instruction information: • Maximum lamp wattage • Type of lamp • For supply connections, use wire rated for at least 8C • Type-IC • Type Non-IC • Suitable for wet locations • Thermally protected Installing and Connecting Luminaires The circuit conductors in a wall or ceiling box where luminaires are to be installed are usually • white-the "identified" grounded conductor, and • black-the ungrounded "hot" conductor. A "hot" switch leg might also be red or another color, but never white or green. Most surface-mounted luminaires will have a black and a white conductor in the canopy, making it easy to match these conductors to the circuit conductors in the box-white to white, black to black. Chain-suspended luminaires usually come with a flexible, flat parallel conductor cord that weaves through the links of the chain. In a cord, it's a little more difficult to make a distinction between the "hot" conductor and the "identified" conductor. To ensure proper polarity when making up the cord connections, generally connect as follows: • The conductor with round insulation connects to the black "hot" circuit conductor. • The conductor with grooved or raised insulation is the "identified" conductor that connects to the white circuit conductor. • In some instances, the "identified" conductor will be tinned so it will have a silver color. • The bare equipment grounding conductor (EGC) from the luminaire connects to the green hexagon-shaped screw in a metal electrical box or on the luminaire's mounting bar. Nonmetallic boxes will have a bare EGC from the nonmetallic-sheathed cable(s) to which the luminaire's bare EGC is connected. FGR. 1 If they are to be mounted on low-density cellulose fiberboard, surface-mounted fluorescent luminaires must be marked "Suitable for Surface Mounting on Low-Density Cellulose Fiberboard." Surface-Mounted Luminaires These are easy to install. It is simply a matter of following the manufacturers' instructions furnished with the luminaires. The luminaire is attached to a ceiling outlet box or wall outlet box using luminaire studs, hickeys, bar straps, or luminaire extensions. Do not exceed the maximum lamp wattage marked on the luminaire. Special attention must be given when installing surface-mounted luminaires on low-density cellulose fiberboard, Fgr. 1. Because of the potential fire hazard, 410.136(B) states that fluorescent luminaires that are surface mounted on this material must be spaced at least 1½ in. (38 mm) from the fiber board surface unless the fixture is marked "Suitable for Surface Mounting on Low-Density Cellulose Fiberboard." The Informational Note to 410.136(B) explains combustible low-density cellulose fiberboard as sheets, panels, and tiles that have a density of 20 lb/ft^3 (320 kg/m^3 ) or less that are formed of bonded plant fiber material. It does not include fiberboard that has a density of over 20 lb/ft^3 (320 kg/m^3) or material that has been integrally treated with fire-retarding chemicals to meet specific standards. Solid or laminated wood does not come under the definition of combustible low density cellulose fiberboard. To obtain fire-resistance ratings, most acoustical ceiling panels today are made from mineral wool fibers or fiberglass. === FGR. 2 Typical recessed luminaire. === FGR. 3 (A) is a Type Non-IC recessed luminaire that requires clearance between the luminaire and the thermal insulation. (B) is a Type IC recessed luminaire that may be completely covered with thermal insulation. (C) shows the required clearances from thermal insulation for a Type Non-IC luminaire. See 410.66. (Cooper Lighting [A, B]) RECESSED LUMINAIRE "X" = a distance of at least 3 in. (75 mm). Insulation above the luminaire must not trap heat. Insulation must be installed to permit free air circulation, unless the luminaire is identified for installation directly in thermal insulation. THERMAL INSULATION == = Recessed Luminaires Recessed luminaires as shown in Fgr. 2 have an inherent heat problem. They must be suitable for the application and must be installed properly. It is absolutely essential for the electrician to know early in the roughing-in stages of wiring a house what types of luminaires are to be installed. This is particularly true for recessed-type luminaires. To ensure that such factors as location, proper and adequate framing, and possible obstructions have been taken into consideration, the electrician must work closely with the general building contractor, carpenter, plumber, heating contractor, the thermal insulation installer, and the other building trades. When working with recessed luminaires, you will come across unique terms such as: • Type Non-IC: See Fgr. 3(A). This type of luminaire is marked "Type Non-IC" and is for installations in noninsulated ceilings. Where installed in an insulated ceiling, thermal insulation must be kept at least 3 in. (75 mm) away from any part of the luminaire. • Type IC: See Fgr. 3(B). This type of luminaire is marked "Type IC" and is permitted to be buried in thermal insulation. • Inherently Protected: This type of luminaire is designed so that the outside surfaces of the luminaire do not exceed temperatures greater than 194°F (90°C)-even if buried in thermal insulation, if mislamped (a lamp type not specified on the product), or if overlamped (lamp wattage exceeds the maximum wattage rating marked on the product). It is marked "Inherently Protected." === FGR. 4 One type of recessed luminaire thermal protector. (--) Open; Closed === When a Type Non-IC recessed luminaire gets overheated because of overlamping, mislamping, or being too close to thermal insulation, the thermal protector ( Fgr. 4) trips off. When the luminaire cools down, it comes on again. This on-off cycling will repeat until the problem is corrected. These luminaires are marked "Blinking Light of This Thermally Protected Luminaire May Indicate Overheating." In the trade, recessed luminaire housings are commonly referred to as "cans." Installing recessed luminaire housings requires more attention than simple surface-mounted luminaires. The Code requirements for the installation of recessed luminaires are found in 410.110 through 410.122. UL Standard 1571 covers recessed incandescent luminaires. Fgr. 3(C) is a sketch that summarizes the minimum clearances for a Type Non-IC recessed luminaire that is not listed for direct burial in thermal insulation, 410.116(B). Recessed luminaires are available for both new work and remodel work. Remodel work recessed luminaires can be installed from below an existing ceiling by cutting a hole in the ceiling, bringing power to the luminaire, making the electrical connections in the integral junction box on the luminaire, then installing the housing through the hole. Energy-Efficient Housings Many states have residential energy-efficiency requirements, particularly for recessed luminaires. The most widely followed regulations are the State of California Title 24 requirements, and the State of Washington Restricted Air Flow Requirements. Basically, these recessed "cans" have double walled gasketed airtight housings that prevent heated or cooled air to escape into attics and other unconditioned spaces in the house. They are listed for use in insulated ceilings and in direct contact with insulation. Although energy-efficiency requirements generally are not applicable to new one- and two-family homes, they might have been adopted by your state or community. Check with your local electrical inspector and/or building official to see whether such laws are applicable in your area for one- and two-family dwellings. FGR. 5 Roughing-in box of a recessed luminaire with mounting brackets and junction box (wiring compartment). (--) === FGR. 6 Requirements for installing recessed luminaires. "LISTED" PREWIRED LUMINAIRE WITH JUNCTION BOX: These boxes must be accessible, 314.29 All incandescent recessed luminaires must have thermal protection and be so marked. Thermal protection not required if identified as being inherently protected by design and construction, 410.115. For "fixture whips," the maximum distance to last support is 6 ft (1.8 m) except for NM and NMC, where the maximum distance to support is 4 1/2 ft (1.32 m). Branch-circuit conductors with insulation suitable for the temperature requirements marked on the "listed" prewired recessed luminaire may be run directly to junction box on luminaire, 410.117(B). Junction box at least 12 in. (300 mm) from luminaire, 410.117(C) Keep insulation at least 3 in. (75 mm) from luminaire unless it is suitable for direct contact with insulation, 410.116(B) Adjacent combustible material temperature not to exceed 194°F (90°C), 410.115 and 410.118 Clearances: • Type Non-IC: At least 1/2 in. (13 mm) from combustible material, except at support, 410.116(A)(1) • Type IC: No minimum clearance, 410.116(A)(2) If flex metal conduit, may be trade size 3/8, 348.20(A) "LISTED" LUMINAIRE WITHOUT JUNCTION BOX === Thermal Protection To protect against the hazards of overheating, UL and the NEC in 410.115(C) require that recessed luminaires be equipped with an integral thermal protector, as in Fgr. 4. These devices will cycle on and off repeatedly until the heat problem has been resolved. There are two exceptions to this requirement. Thermal protection is not required for recessed incandescent luminaires designed for installation directly in a concrete pour, or for recessed incandescent luminaires that are constructed so as to not exceed "temperature performance characteristics" equivalent to thermally protected luminaires. These luminaires are so identified. What the Junction Box (Wiring Compartment) on the Recessed Luminaire Housing Is For Most recessed luminaires come equipped with a junction box (wiring compartment) that is an integral part of the luminaire housing. This is clearly shown in Fgrs. 7-2 and 7-5. For most residential-type recessed luminaire installations, nonmetallic-sheathed cable or armored cable can be run directly into this junction box. These cables are required to have conductors rated 90°C. Check the marking on the luminaire for supply conductor temperature requirements. Fgr. 6 shows the clearances normally needed between recessed luminaires and combustible framing members. This figure also summarizes the NEC requirements for connecting the supply conductors to a recessed luminaire. Note in one case that the branch-circuit wiring is brought directly into the integral junction box on the luminaire. In the other case, a "fixture whip" is run from an adjacent junction box to the luminaire. In some instances, the luminaire comes with a flexible metal "fixture whip," and in other situations the "fixture whip" is supplied by the electrician. "Fixture whips" are discussed later. In 410.21, we find that Luminaires shall be of such construction or installed so that the conductors in outlet boxes shall not be subjected to temperatures greater than that for which the conductors are rated.* NEC 410.21 further states that Branch-circuit wiring, other than 2-wire or multiwire branch circuits supplying power to luminaires connected together, shall not be passed through an outlet box that is an integral part of a luminaire unless the luminaire is identified for through-wiring.* In 410.64, we find that Luminaires shall not be used as a raceway for circuit conductors unless listed and marked for use as a raceway.* Some recessed luminaires are marked "identified for through-wiring," in which case branch circuit conductors in addition to the conductors that supply the luminaire are permitted to be run through the outlet box or wiring compartment on the luminaire. A typical label will look like Fgr. 7. The manufacturer of the luminaire, following UL requirements, will determine the maximum number, size, and temperature rating for the conductors entering and leaving the outlet box or wiring compartment, and will so mark the label. Only those luminaires that have been tested for the extra heat generated by the additional branch circuit conductors will bear the label marking shown in Fgr. 7. These fixtures have been tested for the added heat generated by the additional branch-circuit conductors. Fgr. 8 shows three recessed luminaires, each with an integral outlet box. If these luminaires are marked "Identified for Through-Wiring," then it would be permitted to run conductors through the outlet boxes in addition to the conductors that supply the luminaires. If the "Identified for Through-Wiring" marking is not found on the luminaire, then it is a Code violation to run any conductors through the box other than the conductors that supply the luminaires that are "daisy chained." === FGR. 7 A typical label found on a recessed luminaire specifying the maximum number and size of conductors permitted to be run through the wiring compartment on the luminaire. (--) Maximum of ___ ___ AWG through branch-circuit conductors suitable for at least ___8C (___8F) permitted in a junction box (___ in ___ out). === FGR. 8 The only conductors permitted to run into or through the junction boxes on the recessed luminaires are those that supply the luminaires. Conductors other than those that supply the luminaires are permitted to run through the outlet boxes if the luminaire is marked "Identified for Through-Wiring." See 410.21 and 410.64. (--) === Routing the Branch Circuit Some electricians prefer to run the branch circuit wiring to the junction box on the recessed luminaire, then drop the switch loop to the switch box location. Others prefer to run the branch circuit to the switch location, then to the junction box on the luminaire. Either way is acceptable. A new requirement was added to 404.2(C). It requires: If switches control lighting loads supplied by a grounded general purpose branch circuit, a grounded circuit conductor shall be provided at the switch location. Two exceptions follow. This rule is extensively discussed in Section 5 of this text. As will be seen after reviewing the material, it will be simpler and save on the number of conductors required if the circuit wiring is routed through the switches rather than through the luminaire. Recessed Luminaire Trims There seems to be an endless choice of trims for recessed luminaires: eyeball, open, baffled, cone, pinhole, wall wash, and so on. Be very careful when choosing a trim for a recessed luminaire. Recessed incandescent luminaires are listed by the NRTL with specific trims. Luminaire/trim combinations are marked on the label. Do not use trims that are not listed for use with the particular recessed luminaire. Installing a trim not listed for use with a specific recessed luminaire can result in overheating and possible on-off cycling of the luminaire’s thermal protective device. Mismatching luminaires and trims is a violation of 110.3(B) of the NEC, which states that Listed or labeled equipment shall be installed or used in accordance with any instructions included in the listing or labeling. Sloped Ceilings Be very careful when selecting recessed luminaires. Conventional recessed luminaires are listed for installation in flat ceilings, not in sloped ceilings! Recessed luminaires intended for installation in a sloped ceiling are submitted to the NRTL specifically for testing in a sloped ceiling. Look for the marking "Sloped Ceiling." Instructions furnished with recessed luminaires provide the necessary information, such as being suitable for sloped ceilings having a 2/12, 6/12, or 12/12 pitch. Check the manufacturer's catalog and the NRTL listing. FGR. 9 Suspended ceiling luminaires. Suspended Ceiling Lay-In Luminaires Fgr. 9 illustrates luminaires installed in a typical suspended ceiling. The recreation room of this residence has a "dropped" suspended acoustical paneled ceiling. Luminaires installed in a "dropped" ceiling must bear a label stating "Suspended Ceiling Luminaire." These types of luminaires are not classified as recessed luminaires because in most cases there is a great deal of open space above and around them. Support of Suspended Ceiling Luminaires In 410.36(C), we find that when framing members of a suspended ceiling grid are used to support luminaires, all framing members must be securely fastened together and to the building structure. It is the responsibility of the installer of the ceiling grid to do this. All lay-in suspended ceiling luminaires must be securely fastened to the ceiling grid members with bolts, screws, or rivets. Listed clips supplied by the manufacturer of the luminaire are also permitted to be used. Clips that meet this criteria are shown in Fgr. 1. The logic behind all of the "securely fastening" requirements is that in the event of a major problem such as an earthquake or fire, the luminaires will not fall down and injure someone. === FGR. 10 A suspended ceiling luminaire connected with a flexible fixture whip between an outlet box and the luminaire. Flexible metal conduit and liquid tight flexible metal conduit suitable as equipment grounding means if not over 6 ft (1.8 m) long, branch-circuit overcurrent device is not over 20 amperes, and fittings are listed 250.118(6) and 250.118(7). Conductors in flexible connection (fixture whip) must be suitable for temperature requirements as specified on luminaire labeling, 410.117. SUSPENDED CEILING LUMINAIRE This space accessible from below ceiling by lifting out panels. Fixture whip. See text for wiring methods permitted for fixture whips. Suspended ceiling Tie wires Outlet box === Connecting Suspended Ceiling Luminaires The most common way to connect suspended ceiling lay-in luminaires is to complete all of the wiring above the ceiling using conventional wiring methods. Then, from accessible outlet boxes strategically placed above the ceiling near the intended location of the lay-in luminaires, a flexible connection not more than 6 ft (1.8 m) long is made between the outlet boxes and the luminaires. See Fgr. 10. Lay-in ceiling tiles provides access to these outlet boxes. In the electrical trade, these flexible connections are referred to as "fixture whips." The NEC does not have a definition of a "fixture whip." Don't confuse a "fixture whip" with a "tap." Most fixture whips in residential installations have conductors the same size as the branch-circuit conductors, so the "whip" is really an extension of the branch circuit, and by the NEC definition is not really a "tap." A "tap" is defined in 240.2 as a conductor that has overcurrent protection ahead of its point of sup ply that exceeds the maximum overcurrent protection for that conductor. This is quite common in commercial installations where the branch-circuit overcurrent protection is rated 20 amperes and the tap conductors are rated 15 amperes. Tap conductors must be in a suitable raceway or Type AC or MC cable of at least 18 in. (450 mm) but not more than 6 ft (1.8 m) in length. A fixture whip might be: • armored cable (AC), 320.30(D)(3). • metal-clad cable (MC), 330.30(D)(2). • nonmetallic-sheathed cable (NM and NMC), 334.30(B)(2). • flexible metal conduit (FMC): Okay to use trade size 3/8, 348.30(A), Exceptions No. 3 and No. 4. If trade size 3/8, length is not to exceed 6 ft (1.8 m), 348.20(A)(2). • liquidtight flexible metallic conduit (LFMC): Okay to use trade size 3/8, 350.30(A), Exceptions 3 and 4. If trade size 3/8, length is not to exceed 6 ft (1.8 m), 350.20(A). • liquidtight flexible nonmetallic conduit (LFNC): Okay to use trade size 3/8, 356.30(2). If trade size 3/8, length is not to exceed 6 ft (1.8 m), 356.20(A). Where grounding is required, a separate equipment grounding conductor shall be installed, 356.60. Install according to Article 250. Size per Table 250.122. • electrical nonmetallic-tubing (ENT), 362.30(A). Trade size smaller than ½ is not permitted, 362.20(A). Where grounding is required, a separate equipment grounding conductor shall be installed, 362.60. Install according to Article 250. Size per Table 250.122. Note: For the above wiring methods, the maxi mum distance to the last point of support is 6 ft (1.8 m), except for NM and NMC, where the maximum distance to the last point of support is 4½ feet (1.32 m). Grounding Luminaires Generally, all luminaires must be grounded, 410.42. Assuming that the wiring is a metallic wiring method or nonmetallic-sheathed cable with an equipment grounding conductor, you have an acceptable equipment grounding connection at the lighting outlet. Grounding of a surface-mounted luminaire is easily accomplished by securing the luminaire to the properly grounded metal outlet box with the hardware provided with the luminaire. Metal outlet boxes have a tapped No. 10-32 hole in which to insert a green hexagonal grounding screw. The bare copper equipment grounding conductor in the nonmetallic-sheathed cable is usually terminated under this screw. Grounding and bonding is discussed in Section 5. If the outlet box is nonmetallic, the small bare equipment grounding conductor from the luminaire is connected to the equipment grounding conductor in the outlet box. For suspended ceiling luminaires, grounding of the luminaire is accomplished by using metallic fixtures whips or nonmetallic-sheathed cable with ground between the outlet box and the luminaire. Always follow the manufacturers' instructions for making the electrical connections. What about replacing a luminaire in an older home? If there is no equipment grounding means in the outlet box, then a luminaire that is made of insulating material and has no exposed conductive parts must be used, 410.44 Exception No. 1. Exception No. 2 to 410.44(B) allows a metallic replacement luminaire to be installed and connected to a system that does not have an equipment grounding conductor. In this case, a separate equipment grounding conductor must be installed in conformance with 250.130(C). This requirement is discussed in Section 6 in the topic of replacing receptacles, so it is not repeated here. Exception No. 3 to 410.44(B) allows a metallic replacement luminaire to be installed and connected to a branch circuit that does not have an equipment grounding conductor if it is protected by GFCI device. Acceptable types of equipment grounding conductors are listed in 250.118. In Section 17, Fgrs. 17-1 and 17-2 have additional information regarding recessed luminaire installations such as those in the recreation room of this residence. Luminaires in Closets There are special requirements for installing luminaires in closets. This is covered in Section 8. Luminaires in Bathrooms Because of the electrical shock hazards associated with electricity and water, there are special restrictions for luminaires installed in bathrooms. This is covered in Section 10. FLUORESCENT BALLASTS AND LAMPS, INCANDESCENT LAMPS The following is a brief introduction to a complex subject. For much more information, check out lamp and ballast manufacturers' Web sites listed in the Appendix of this text. From an electrician's point of view, lamps and light bulbs mean the same thing. Use any one of the words, and everyone will know what you mean. Always read the label on a luminaire for the type and maximum wattage of the lamp to be installed in that luminaire. Fluorescent Ballasts An incandescent lamp contains a filament that has a specific "hot" resistance value when operating at rated voltage. When energized, the lamp will provide the light output for which the lamp was designed. A fluorescent lamp, on the other hand, cannot be connected directly to a circuit. It needs a ballast. Fluorescent lamps do not have a filament running from end to end. Instead, they have a filament at each end. The filaments are connected to a bal last, as in Fgr. 11. The ballast is needed to (1) control power, (2) control voltage to heat the filaments, (3) control voltage across the lamp to start the arc within the tube, and (4) limit the cur rent flowing through the lamp. The arc is needed to ionize the gas and vaporize the droplets of mercury inside the lamp. Without a ballast, the lamp would probably not start. But if it did start, it would "run away" with itself. The current flowing through the gases within the lamp would rise rapidly, destroying the lamp in a very short time. ===== FGR. 11 Simple series circuit. BALLAST 20-watt fluorescent lamp Starter 120-volt supply ===== Ballast Types Preheat. Preheat ballasts are connected in a simple series circuit, Fgr. 11. They are easily identified because they have a "starter." One type of starter is automatic and looks like a small roll of Lifesavers with two "buttons" on one end. Another type of starter is a manual "ON-OFF" switch that has a momentary "make" position just beyond the "ON" position. When you push the switch on and hold it there for a few seconds, the lamp filaments glow. When the switch is released, the start contacts open, an arc is initiated within the lamp, and the lamp lights up. Preheat lamps have two pins on each end. Preheat lamps and ballasts are not used for dimming applications. Rapid Start. Probably the most common type used today. Rapid start ballasts/lamps do not require a starter. The lamps start in less than 1 second. For reliable starting, ballast manufacturers recommend that there be a grounded metal surface within ½ in. (12.7 mm) of the lamp and running the full length of the lamp, that the ballast be grounded, and that the supply circuit originates from a grounded system. T5 rapid start lamps do not require a grounded surface for reliable starting. Rapid start lamps have two pins on each end. Rapid start lamps can be dimmed using a special dimming ballast. See Section 13. Instant Start. Instant start lamps do not require a starter. These ballasts provide a high-voltage "kick" to start the lamp instantly. They require special fluorescent lamps that do not require preheating of the lamp filaments. Because instant start fluorescent lamps are started by brute force, they have a shorter life (as much as 40% less) than rapid start lamps when older style magnetic ballasts are used. With electronic bal lasts, satisfactory lamp life can be expected. Instant start lamps have one pin on each end. Instant start ballasts/lamps cannot be used for dimming applications. Dimming Ballasts. Special dimming ballasts and dimmers are needed for controlling the light output of fluorescent lamps. Rapid start lamps are used. Incandescent lamp dimmers cannot be used to control fluorescent lamps. An exception to this is that dimmers marked "Incandescent Only" can be used to dim compact fluorescent lamps. Dimming bal lasts are discussed in Section 13. Mismatching of Fluorescent Lamps and Ballasts Be sure to use the proper lamp for a given bal last. Mismatching a lamp and ballast may result in poor starting and poor performance, as well as shortened lamp and/or ballast life. The manufacturer's ballast and/or lamp warranty may be null and void. T8 lamps are designed to be used interchange ably on magnetic or electronic rapid-start ballasts or electronic instant-start ballasts. Lamp life is reduced slightly when used with an instant-start ballast. Voltage: Operating a ballast at an over-voltage condition will cause the it to run hot and shorten its life. Operating a ballast at an under-voltage situation can result in premature lamp failure and unreliable starting. Most ballasts today will operate satisfactorily within a range of 15% to 27% of their rated volt age. The higher quality CBM certified ballasts will operate satisfactorily within a range of 610%. Sound Rating Most ballasts will hum, some more than others. Ballasts are sound rated and are marked with letters "A" through "F." "A" is the quietest, and "F" is the noisiest. Look for an "A" or "B" sound rating for residential applications. Magnetic ballasts (core and coil) hum when the metal laminations vibrate because of the alternating current reversals. This hum can be magnified by the luminaire itself, and/or the surface the luminaire is mounted on. Electronic ballasts have little, if any, hum. CAUTION: Do not insert spacers, washers, or shims between a ballast and the luminaire to make the ballast more quiet. This will cause the ballast to run much hotter and could result in shortened ballast life and possible fire hazard. Instead, replace the noisy ballast with a quiet, sound-rated one. Sometimes checking and tightening the many nuts, bolts, and screws of the luminaire will solve the problem. Energy Saving by Control: We have all heard the words "Shut off the lights when you leave the room." Sometimes this works- sometimes not. This text is used in all 50 states in this country and in Canada. It is not the intent of this text to go into the detail of specific state and/or local energy requirements. Just be aware that new developments are happening relative to energy conservation, and you need to pay attention. As an example, the State of California recently put into place Title 24, Part 6. The intent is to reduce power consumption in new homes. The States of Washington and Wisconsin have stringent energy conservation laws. As time passes, other states will follow. The Energy Policy Act of 2005 stipulates in Title XII the electricity that types of lamps are permitted based on lumens per watt (efficacy). This law in Section 1252 also calls for utilities to provide "time-based" metering for residential, commercial, and industrial customers. Customers then can vary their electrical demands based on the rates for different times of usage. You can learn more about this by visiting the government's Web site: http://energycommerce.house.gov/. As you install residential lighting, you need to be familiar with the terms "efficacy" and "lumens per watt." Simply stated, efficacy is measured in lumens per watt. This law simply requires that lamps in permanently installed luminaires • have high-efficacy rating (high lumens per watt), or • be controlled by occupancy sensors, or • have a combination of lamp efficacy, occupancy sensor control, and/or dimmers. Cord-connected floor or table lamps are not governed by present current energy conservation laws. Most fluorescent lamps with energy-saving ballasts, compact fluorescent lamps (CFL), and halogen lamps meet this high-efficacy requirement. Conventional incandescent lamps do not. See Table 2 to view the comparison of lumens per watt for different types of lamps. The following chart shows what is required to meet the lamp requirement. === Lamp Wattage Lamp Efficacy Less than 15 watts 40 lumens per watt 15-40 watts 50 lumens per watt Over 40 watts 60 lumens per watt === === Table 2 Comparison of various lamps' characteristics. These characteristics are typical, and will vary by manufacturer. Always verify application with lamp and luminaire manufacturer's label, literature, and installation instructions. Type of: Lamp | Lumen per Watt | Dimming | Color and Application | Life (approx. hours) | Typical Shapes [[[ Incandescent 14-18 Yes Warm and natural. Great for general lighting. Brand names have various trade names for their lamps, such as Reveal, Soft White, etc. 500, 750, 1000, 1500, 3000 hours. Depends on type of lamp. Lamp life typically is based on operating the lamp an average of 3 hours of operation per start. Standard, spots, floods, decorative, flame, tubes, globes, PAR (similar to standard spots and floods but stronger). Use rough service bulbs where there is vibration, like garage door openers and ceiling fans. Base types: candelabra, intermediate, medium, mogul. Halogen 16-22 Are more efficient than conventional incandescent lamps. More lumen output per watt. Yes Brilliant white. Excellent for accent and task lighting. Are filled with halogen gas and floods and have an inner lamp, allowing the filament to run hotter (whiter). 2000-4000 hours. Lamp life typically is based on operating the lamp an average of 3 hours of operation per start. PAR spots and floods, flame, crystal, mini reflector spots. Base types: candelabra, intermediate, and medium. Can replace most incandescent lamps. Fluorescent T12 82 T8 92 T5 104 Yes, but only 40-watt rapid-start lamps using special dimming ballast. See Section 13. Warm and deluxe warm white, cool and deluxe cool white, plus many other shades of white. Great for general lighting, like the Recreation Room in this residence. The higher the K rating, the cooler (whiter) is the color rendition. 6000 to 24,000 hours. Average life with lamps turned off and restarted once every 12 operating hours. Straight, U-tube, circular. Single pin and double pin. Compact Fluorescent (CFL) 45/60 Because of their high lumens per watt, CFLs can save $20 to $50 over their lifetime when compared to equivalent incandescent lamps. Produce more lumens per watts (e.g., 27-watt CFL produces 1800 lumens vs. 1750 for a 100-watt incandescent.) Use about 80% less energy, and generate 90% less heat than equivalent incandescent lamp. Yes, if so marked. CFLs have integral ballasts. Soft warm white. 10,000-15,000 hours. Can last 9 to 13 times longer than incandescent. Lamp life typically is based on operating the lamp an average of 3 hours of operation per start. Read instructions carefully for restrictions such as Not for use with dimmers, electronic timers, occupancy sensors, photocells, or lighted switches, Do not use in recessed or totally enclosed luminaires. Twisted (spiral) tubes, folded tubes, globe. R20, R30, R40, PAR38, "A" shape (like a standard incandescent). The number of tube loops are referred to as twin, double twin, triple twin, quad twin. Base types: medium. Can replace most incandescent lamps. Light-Emitting Diodes (LED) 501 An LED lamp contains a cluster (array) of many individual LEDs to produce this lumen output. Yes or No. Check manufacturer's instructions and warnings. White for LED lighting. 60,000 to 100,000 hours. Base type: medium. Can replace an incandescent lamp. ]]] The Bottom Line: In a nutshell, this amounts to the mandatory use of high-efficiency luminaires (air-tight), high efficiency lamps, and various levels of control such as occupancy sensors and dimmers. Today, occupancy sensor switches are available that install the same way as conventional toggle switches. They provide manual "ON-OFF" as well as automatic shut-off when no motion is detected after a preset time. As soon as motion is detected, they turn the lamps on. See Fgr. 12. To learn more about the California energy conservation law, check out energy.ca.gov/ title24 and http://www.haloltg.com. Browse for the summary of the California Title 24 law. Other lighting manufacturers' Web sites should also be checked out. Energy-Saving Ballasts---The market for magnetic (core and coil) ballasts is shrinking! The National Appliance Energy Conservation Amendment of 1988, Public Law 100-357 prohibited manufacturers from producing ballasts having a power factor of less than 90%. Ballasts that meet or exceed the federal standards for energy savings are marked with a letter "E" in a circle. Dimming ballasts and ballasts designed specifically for residential use were exempted. Today's electronic ballasts are much lighter in weight and considerably more energy efficient than older style magnetic ballasts (core and coil). Energy saving ballasts might cost more initially, but the pay back is in the energy consumption saving over time. Old-style fluorescent ballasts get very warm and might consume 14 to 16 watts, whereas an electronic ballast might consume 8 to 10 watts. Combined with energy-saving fluorescent lamps that use 32 or 34 watts instead of 40 watts, energy savings are considerable. You are buying light, not heat. When installing fluorescent luminaires, check the label on the ballast that shows the actual volt-amperes that the ballast and lamp will draw in combination. Do not attempt to use lamp wattage only when making load calculations because this could lead to an over loaded branch circuit. For example, a high-efficiency ballast might draw a total of 42 volt-amperes, whereas an old-style magnetic ballast might draw 102 volt amperes. Refer to Table 3 for other comparisons. The higher the power factor rating of a ballast, the more energy efficient. Look for a power factor rating in the mid to high 90s. FGR. 12 An occupancy (motion) sensor. FGR. 13 An electronic Class P ballast, thermally protected as required in 410.130(E). Electronic ballasts provide improved performance in fluorescent lighting installations. Electronic ballast lighting systems are 25% to 40% more energy efficient than conventional magnetic (core & coil) ballast fluorescent systems. (SRAM Sylvania) ==== Table 3 Various line currents, volt-amperes, wattages, and overall power factor for various single-lamp fluorescent ballasts. Ballast Line Current Line Voltage Line Volt-Amperes Lamp Wattage Line Power Factor No. 1 0.35 120 42 40 0.95(95%) No. 2 0.45 120 54 40 0.74(74%) No. 3 0.55 120 66 40 0.61(61%) No. 4 0.85 120 102 40 0.39(39%) No. 5 0.22 120/277 26 30 0.99(99%) These values were taken from actual ballast manufacturers' data. For two-lamp ballasts, double the values in this table. Note in line 5 how high the efficiency is of the latest type of electronic, high performance ballast for T8 fluorescent lamps. ==== Next>> Prev. | Next |