Final Exam

Question 1

Ohm’s Law

Answer 1

Volts = Ampere x Ohms or V = I x R

Question 2

Equation for watts

Answer 2

P = V x I (power = volts x amperes)

Question 3

AC voltages can be changed easily between one AC voltage and another AC voltage through:

Answer 3

Transformers (step up or step down).

• AC transmission voltages are stepped down from high voltage down to line voltage for use in our homes
• In Rectifiers the first step is reducing the line voltage 120V down to a smaller 12V using transformers
• AC transmission voltages are stepped up after the generator to reduce transmission losses
• In some audio equipment, low AC voltages are increased to drive speakers to create sound

Question 4

DC voltages can be changed to other higher or lower DC voltages through:

Answer 4

DC to DC Converter

Your car battery at 12 VDC supplies electronics that only require 5V or less and those are obtained by DC-DC conversion.

Question 5

Alternating Current (AC)

Answer 5

: is an electric current (in Amperes) that reverses direction multiple times within each second.
AC: 60 cycles per second (or 60 Hertz) in USA (UNIT: 1 Hertz or one cycle per second). 50 Hz exists in some other countries.
USA: has 240 VAC and 120 VAC for home use (you can combine two out of phase 120 V circuits into a 240 V)
USA: has 277 VAC and 120 VAC for commercial use.
The 120 VAC is root mean square (RMS) voltage whereas the actual peak voltage is 170 VAC.

Question 6

Fuse or circuit breaker:

Answer 6

over current protection devices (excess current above that which the circuit was designed to carry. e.g. 15A circuit breaker trips when current in excess of 15A is used).

Question 7

Junction Box purpose

Answer 7

Every time there is a break in a wire (to connect receptacle or switch, or you splice two short wires together), they must be contained within a Box (Junction Box) specifically designed to accommodate wires and cables.

Question 8

Receptable codes

Answer 8

15A circuit: max no. receptacles = 10
20A circuit: max receptacles = 13. Kitchens require at least 2, 20A circuits.
A receptacle is required every 12 linear feet and any wall over 2 feet wire.
Specialty receptacles are necessary near moisture – GFCI and must be tested regularly to ensure operation.

Question 9

Single Pole –

Answer 9

on/off from one location.

Question 10

Three-way –

Answer 10

open/close a circuit from two different locations (used in pairs – they do not have on/off markings!).

Question 11

Four-way –

Answer 11

used in between the three-way switches at the beginning and end of a run, to add additional points of on/off.

Question 12

Low voltage

Answer 12

Low Voltage is considered wiring and trim that doesn’t carry the same current as power outlets, fixtures and switches as traditional CODE regulated wiring (usually less than 50V but not specifically defined in CODE). Telephone wire and telephone jacks, security wires (CAT5e or CAT6), fiber optics, speaker wires and television cables (RG-6) are all considered low voltage (also known as Structured Cabling) and are part of distributing audio, video and data. There are specific installers who install these low voltage cables and fixtures compared to conventional Electricians.
When designing a new or renovated space, take into consideration services that will require low voltage access. Locating outlets for telephone, cable, intercoms, security systems (panels, cameras, sensors) as well as providing power at those locations is part of a complete interior design.

Question 13

ELECTROMAGNETIC RADIATION

Answer 13

pg 19

Question 14

LIGHT

Answer 14

is the set of wavelengths (or the frequency range) of electromagnetic radiation that can be detected by our eyes.

Question 15

LIGHT

Answer 15

is inclusive of all optical radiation from short wavelength UV (or ultra-violet – that is the cause of sunburn UV-A, B and C) to long-wavelength IR (or infra-red radiation – that warms you from a fire or heating element) as well as the Visible Spectrum including red, orange, yellow, green, blue, indigo and violet and all colors continuously between them.

Question 16

A FULL SPECTRUM light is

Answer 16

defined as giving off all colors / wavelength EQUALLY.

The SUN – is a NATURAL source of light and is considered FULL SPECTRUM and has a CONTINUOUS SPECTRUM.

Question 17

A PARTIAL SPECTRUM light is

Answer 17

defined by giving off unequal amounts of partial colors across the spectrum.
A LAMP – is an ARTIFICIAL source of light and is rarely FULL SPECTRUM and has missing spectral components.

Question 18

Downside of Thermal light sources (incandescent, halogen)

Answer 18

Energy wasted as radiation is given off as heat (80-90% waste) with only 5% of power converted into light – Low LPW

Question 19

Downside of Thermal light sources (incandescent, halogen)

Answer 19

Energy wasted as radiation is given off as heat (80-90% waste) with only 5% of power converted into light – Low LPW

Question 20

Solid state / LED benefits

Answer 20

The most efficient devices available for conversion of electricity into light coupled with long lifetimes.
The sizes are extremely small allowing new form factors to be designed.
The best of these devices can yield extremely high quality and high quantity light output.
Very lightweight and easy to conceal. Excellent for aviation, commercial displays and artistic installations.

Question 21

LED LIFETIME:

Answer 21

25,000 - 50,000 hours of operation (for the LED – the fixture rating including power supply is always less).

Question 22

COMPARISON between various common LAMPS or light sources – light output, power used, lifetime, price and cost analysis

Answer 22

pg 30

Question 23

Traditional, incandescent light bulbs do not meet the current efficiency standards and are no longer be available at most stores.
In California, retailers are allowed to sell existing inventories of inefficient light bulbs manufactured prior to Jan 1, 2018 (and 2020 for the rest of the nation). For understanding replacement lamps equivalents when switching out existing incandescent lamps, use these rules of thumb:

Answer 23

See chart on pg 31

Question 24

COLOR TEMPERATURE (K):

Answer 24

Color temperature is a way to describe the light appearance provided by a light bulb (lamp).

1. Measured in degrees of Kelvin (K) on a scale from 1,000 to 10,000.
2. For commercial and residential lighting, Kelvin (K) temperatures fall somewhere between 2000K to 6500K.
3. A light bulb’s (lamp’s) color temperature lets us know what the look and feel of the light produced might be.
4. The color temperature of a light bulb (lamp) is assigned using the basis of correlated color temperature (CCT).
5. Terms such as Warm White, Cool White, Daylight describe color temperature ranges.

Question 25

CORRELATED COLOR TEMPERATURE (CCT):

Answer 25

the apparent color of a light source (that is not directly describable by Color Temp).

1. Also defined as the color emitted by a black body emitter heated until light is given off, hotter it is whiter the light becomes.
2. CCT measures the color of a light source using Kelvin (K) temperature.
3. The lower the Kelvin temperature (2700–3000 K), the warmer the color of the light.
4. The higher the temperature (3600–5500 K), the cooler, and more bluish, the light appears.

Question 26

COLOR RENDERING INDEX (CRI): or Color Accuracy

Answer 26

1. CRI: Describes how a light source renders the colors of other objects and surfaces compared to a reference source.
2. Maximum value is 100 which is the equivalent of natural daylight.
3. As the number decreases, the color rendering ability is increasingly distorted.
4. There is no lower limit (and going negative for Low-Pressure Sodium Lighting).
5. It doesn’t say anything about the “color” of the light source itself (that’s CCT).
6. The higher the CRI (>90) the more expensive the lamp. Strive for close to 100 with >90 your base level.
7. Efficiency of LEDS decreases with higher CRI – therefore the best LEDs are not as efficient as cheap LEDs.

Question 27

LUMEN:

Answer 27

A unit of luminous flux (total amount of light emitted from a source). A dinner candle provides about 12 lumens. A 60-watt incandescent bulb provides about 800 lumens. (Note that a lamp or source usually has an Initial, Mean and End of Life lumen value that changes as the lamp ages). You might select a source for its initial lumen output – but for critical applications, they should remain above your desired output level (think of operating room lights – you don’t want them getting dimmer over time).

Question 28

ILLUMINANCE:

Answer 28

the light (total luminous flux) from the source falling onto the surface we are observing. It is the amount of light striking a surface – also known as incident light, where the “incident” is the beam of light actually landing on the surface. Illuminance is calculated as the density of lumens per unit area and is expressed using FOOT-CANDLES (lumens/square foot) in the United States or the metric version, lux (lumens/square meter), elsewhere. Illuminance is measured using a light meter.

Question 29

LUMINANCE:

Answer 29

apparent brightness or intensity in Candelas (cd) per square meter (cd/m2) of the light being reflected off the surface in a given direction. Luminance is literally “What you see”.

Question 30

Illuminance vs. Luminance:

Answer 30

Don’t confuse illuminance with luminance. The former measures the incident of light, luminance measures what leaves, or is reflected from, the surface.

Question 31

Glare:

Answer 31

Excessive brightness creating difficulty in seeing in the presence of bright light, either direct or reflected, in contrast to the luminance required of the task source.

Question 32

Indirect Glare:

Answer 32

From a design point of view, this is very important: Countertops, TV screens, shower/bath glass and mirrors.

Question 33

Contrast:

Answer 33

is determined by the difference in the color and brightness of the object and other objects within the same field of view.

Question 34

The Inverse Square Law:

Answer 34

Light falls off dramatically as it travels from a (point) source. In fact, when the distance away from a light source is doubled, the light does not fall to half the light, but to one quarter of the light. An easy way to remember the inverse square law is to remember that when you double the distance, you get a quarter of the light.
For some sources such as a CFL or Edison Bulb, you can approximate it as a point source for most calculations. For more complex light sources, the manufacturer will supply you with photometric data that describes how light is emitted and controlled.

Question 35

LAMPS:

Answer 35

The replaceable component that produces light from electricity. Typically called Bulbs because of the shape of incandescent lights. You can also refer to this component in a general sense as a light Source. With LED lights there is more confusion that will be explained in another section.

Question 36

LUMINAIRES:

Answer 36

The decorative lighting fixture that houses a LAMP. A complete lighting unit containing the light, ballast/power supply and housing.

Question 37

For purely decorative Lamps and Luminaires you are not concerned with light quantity as much as visual appeal. For more lighting projects, where you need to ensure you have specified the correct lumens and distribution, you will need to use Photometric Data. Depending on the specific Lamp or Luminaire, some test results and data may or may not be provided. Samples:

Answer 37

pg 41

Question 38

History

Answer 38

Natural Light – Always a reliable and free source of light (sun)
Fire & Torches - 70,000 years ago (torches made fire, and hence light, portable)
Candles & the Wick - fourth century BC in Egypt – Asian societies making candles early as 200BC – wick controls burn
Gas Lamps – developed in England in 1790 then in USA in 1792 (dangerous, still used in camping, spurred industry)
Electric Lamps – first versions were arc lamps by Englishman Humphry Davey.

Question 39

What are today’s trends?

Answer 39

1. CONNECTIVITY – wired and wireless control for energy savings and more beautiful and interesting lighting schemes.
2. BUILT-IN SOURCES – with the revolution in LEDS with lifetimes of up to 50,000 (6 years continual use) – no replaceable parts
3. NEW POWER SUPPLY TECHNOLOGIES – new sources require new ways to power them
4. RETROFIT LAMPS – replacing existing low efficacy lamping with “identical form factor” lamping with efficient sources
5. HEALTHIER LIGHTING – better understanding of how light affects our bodies (& plants) pushes new controls and colors.
6. LED EVERYTHING – currently there are very few applications where LEDs cannot be used.

Question 40

Measuring Lamps

Answer 40

1) Bulbs are measured in eights of an inch (1/8”) at their widest diameter. For example, 75PAR30 is 30 eighths of an inch in diameter, or 3.75 inches.
2) Maximum overall length (MOL) of the bulb is measured in inches from end-to-end.
3) A bulb’s base is measured in millimeters. For example, 35W 120V JDR halogen bulb has an E26 medium base, which measures 26mm in diameter.
4) A fluorescent bulb’s base is measured from center pin to center pin. For example, a G13 bi-pin base, measures 13mm from pin to pin.

Question 41

LAMP SHAPES (Encapsulation and Electrical Contacts:

Answer 41

The names of light bulb shapes are denoted with a letter, which describes the shape, and a number, which indicates the size. The number associated with the shape indicates the diameter of the light bulb at its widest part in eighths of an inch.
- For example, an A19 light bulb has a maximum diameter of 19/8 of an inch, or 2.375 inches.

Question 42

A – Appliance light bulbs

Answer 42

Appliance light bulbs are one of the most widely used shapes and can be used almost anywhere, including homes, hotels, and restaurants. Appliance light bulbs have the shape that most consumers think of when they picture a light bulb. Typical sizes include A15, A19, A21, and A23.

Question 43

PAR – Parabolic Aluminized Reflector light bulbs.

Answer 43

PAR light bulbs are reflector light bulbs that have an aluminized reflector in a parabola shape. They are covered with a hard glass lens to control the light beam, which is available in a variety of beam spreads from narrow spot to wide flood. PAR light bulbs can be used outdoors unprotected because their hard glass shell can withstand adverse weather. PAR light bulbs are also used for down lighting applications in recessed cans and track lighting in residential, retail, museums, and art gallery applications. Typical sizes include PAR16, PAR20, PAR30, PAR30 long neck, and PAR38. The PAR30 long neck was introduced to replace incandescent BR30 light bulbs in cans in which standard PAR30 light bulbs did not fit. VNSP: Very narrow spot / NSP: Narrow spot / SP: Spot / NFL: Narrow flood / FL: Flood / WFL: Wide flood / VWFL: Very wide flood

Question 44

MR – Mirror Reflector light bulbs.

Answer 44

MR light bulbs have a mirrored reflector. They are used for accent and spot lighting in various retail, residential, and commercial applications. The most common size is MR16; however, MR11 is also used in limited applications.

Question 45

T – Tube light bulbs.

Answer 45

T light bulbs are shaped like a cylindrical tube. Depending on the size, T light bulbs have very different applications. Incandescent T6 light bulbs are used in exit and stairway signs and picture lights. Linear fluorescent T12, T10, T8, and T5 light bulbs come in a variety of lengths, ranging from 2-8 feet. These light bulbs are placed in fluorescent troffers and are used for general lighting in offices, retail outlets, hospitals, and parking garages. The # after the T designation is how wide the tube diameter is in 1/8th inch increments (T8= 8/8”= 1in).

Question 46

Spiral – Spiral Tube light bulbs.

Answer 46

The spiral light bulb is the shape of a compact fluorescent light bulb. A smaller diameter fluorescent T light bulb, such as T4, T3, T2, or T1, is twisted into a spiral or coil configuration in order to provide the most amount of light output in the least amount of space. Spiral light bulbs are typically used to replace incandescent light bulbs and can be used virtually anywhere, including residential, commercial, retail, hospitality, and restaurant applications.

Question 47

Compact Fluorescent

Answer 47

folded tube lamps are designed with specific pin/socket combinations to prevent the user from changing lamping after installation. They are configured for specific ballast and light out (see pin bases). USUALLY these qualify for Title 24

Question 48

SCREW BASES:

Answer 48

Screw bases are the most common light bulb base. In an incandescent or halogen screw base light bulb, two contact wires connect the filament to the base of the light bulb, where the electrical voltage connects to the light bulb. The contact wires are soldered to the base metal at two different points on the base in order to keep them affixed to the base metal. If the contact wires were not permanently affixed to the base metal, electrical current would not be able to continuously flow through the wires to energize the filament into producing light. One of the contact wires is soldered on the side of the base, and the other is soldered at the bottom. Therefore, the light bulb makes electrical contact at two points on the base.

Question 49

Screw bases come in several sizes, and they are referred to by both a descriptive name and size.

Answer 49

Unlike the light bulb shapes, the number in the light bulb base measures the light bulb base diameter in millimeters. The candelabra E12 has a diameter of 12 millimeters. The “E” in the light bulb size refers to Edison, the inventor of the screw base light bulb, and screw base light bulbs are sometimes called “Edison light bulbs.” Candelabra bases are mostly used in smaller, decorative incandescent lamps. The medium E26 base is the most common light bulb base. It is used in most incandescent, halogen, CFL, CCFL, and HID light bulbs. The mogul E39 base is found in larger sized light bulbs, such as high wattage HID.

Question 50

PIN BASES:

Answer 50

Pin bases are used in MR16s, linear fluorescents, plug-in compact fluorescent bulbs, and some HID light bulbs. Whereas the screw base connects the light bulb to the voltage with two soldered contact wires on the metal base, pin base light bulbs have two pins sticking out of the base that connect the light bulb to the voltage. Electrical current then flows through the pins and into the light bulb to energize the filament or ballast to generate light.
The names of pin bases include a number that measures the distance in millimeters between the two pins from center point to center point. For example, bi-pin GU5.3 bases have two pins that are 5.3 millimeters apart between the center points of each pin.
This base and bi-pin GU10 are used in MR16 light bulbs.
Medium bi-pin G13 bases are used in the vast majority of T8, T10, and T12 linear fluorescent light bulbs.
Some linear fluorescents have a single pin Fa8 or recessed double contact R17d, but they are not very common. Miniature bi-pins are used in T5 linear fluorescents.
T9 HID light bulbs use G12 and recessed single contact (R7S RSC) pin bases.
Plug-in compact fluorescent light bulbs are equipped with a two or four-pin base and use a ballast that has been built into the fixture. Plug-in CFLs cannot be interchanged with the ballast; depending on the ballast, only one or two light bulbs will be compatible with the fixture.
The two-pin bulbs are for use with magnetic ballasts, and the four-pin bulbs are for use with electronic ballasts. The sockets used in plug-in CFL fixtures are designed to work with only one style of pin base. This ensures that the correct wattage light bulb is used to match the type of ballast inside the fixture. Some examples of plug-in CFL pin bases are G23, GX23-2, G24Q-2, and GX24Q-3.

Question 51

2. 2-pin and 4-pin compact fluorescents –

Answer 51

NEEDS BALLAST (usually used in recessed housing and sconces)

Question 52

Fluorescent lamps ballasts come in THREE versions:

Answer 52

1. MAGNETIC (Old technology, cheap, yet flicker and buzz are side issues) – can be swapped out with Electronic types.
2. ELECTRONIC (current technology that continues to improve) and there are three versions:
   a. Rapid Start: a filament in the tube is always on/warm – allowing instant on – but not energy efficient
   b. Instant Start: use less energy but require a higher start voltage.
   c. Programmed Start: usually paired with occupancy or motion sensor to reduce on/off cycles (turning on and off repeatedly uses more energy than if you left the light on).
3. DIMMING (available in magnetic – but now electronic versions specified).
   a. Confirm dimming down to 1% of output lumens – many only dim down to 10% of lumen output.
   b. Can require specific wall dimmer switches compatible with the dimming ballast.

Question 53

What components do you need for a Complete LED Installation Specification?

Answer 53

1. LED (puck, strip, etc.) –
   a. If a puck, each puck has a specific voltage and current requirement as well as a fixed light output.
   b. If a strip, each foot (or m) has a lumen output (e.g. 100 lumens/ft) and a power requirement (e.g. 2.3 W /ft).
2. Power Supply (converts 120 V AC to 12 or 24 V DC)
3. Connectors and/or wiring to connect LEDs with the Power Supply and the Power Supply to the line voltage.
4. Dimmer if needed. Some Power Supplies can include a dimmer, other LEDS require separate dimmer.
5. Mounts for the LEDs (double sided tape, aluminum extrusions) along with end caps, clips, etc. (cut to length at install)
6. Diffuser (especially for LED strips in conjunction with extrusions) – (cut to length at install)
7. Wall Switch You can switch the power supply, however there are also low voltage switches available.

Question 54

LED Design Constraints:

Answer 54

1. Power Supplies provide a specific and limited output power – must size each one to the required power.
2. Power Supplies are also specific to the output voltage – 12 or 24 V DC usually. They are not interchangeable.
3. Power Supplies are never to be used at full specification (e.g. if 3A, must de-rate for daily usage).
4. Long distances between Power Supply and LED must be avoided – resistive losses will lower power delivered, lower light.
5. Power Supplies can be big and bulky – need to discretely hide them. But they need air flow to avoid overheating.
6. Need specific dimmer switches that have been tested with LED system (LED and the Power Supply).
7. Need to match CRI and COLOR TEMP from different manufacturers or form factors within same room.
8. Lumens per module or foot are reduced with diffusers and with longer distances from Power Supply.

Question 55

LIGHTING CONTROLS

Answer 55

• The simplest control of hard-wired lighting is the On-Off switch.
• Added dimming capability changes the mood and function of a space and allows the user to tailor personalize their experience.
• Multi-layered lighting is another way to change the mood and functionality of a space.
• The more layers and sources, the more complex the individual switch banks become (more than 3 switches are cumbersome).
• Programmable Controllers with “presets” allow one button to control multiple sources each with its own programmed dimming.

Question 56

Zones and scenes

Answer 56

LIGHTING CONTROL TERMINOLOGY:
Zone = fixture or group of fixtures that are controlled simultaneously and wired on one circuit
Zone Capacity = maximum capacity limit of watts/VA per zone for an individual control
Scene = Lighting effect achieved by adjusting one or more zones of lighting to desired preset levels (including on and off)
Zones are usually comprised of one type of lamping (since each type of lamp can require different dimming technology). Also, you might have to split one group of lights into two or more to adhere to the Zone Capacity.

Question 57

It can also take in sensor input such as Occupancy/Vacancy Sensors, Daylight Sensors and IR Receivers.

Answer 57

Sensor – detects motion, heat, and partition status and allows automatic control of dimming and switching.
Daylight sensor – sensor that provides feedback to control light levels in response to available daylight.
Occupancy Sensor – either IR or ultrasonic sensor to sense presence of occupants either with heat or motion.

Question 58

National Electric Code:

or NEC,

Answer 58

is a regionally adoptable standard for the safe installation of electrical wiring and equipment in the United States. It is part of the National Fire Codes series published by the National Fire Protection Association (NFPA), a private trade association. Despite the use of the term “national”, it is not a federal law. It is typically adopted by states and municipalities to standardize their enforcement of safe electrical practices. In some cases, the NEC is amended, altered and may even be rejected in lieu of regional regulations as voted on by local governing bodies. Updated every 3yrs.

Question 59

ADA – “AMERICANS with DISABILITIES ACT” and how it pertains to lighting:

Answer 59

1. Objects projecting from walls with their leading edges between 2 feet 4 inches and 6 feet 8 inches above the finished floor and shall protrude no more than 4 inches into walks, halls, corridors, passageways, or aisles.
2. Objects mounted with their leading edges at or below 27 inches above the finished floor may protrude any amount.
3. Freestanding objects mounted on posts or pylons may overhang 12 inches maximum from 27 inches to 80 inches above the ground or finished floor.
4. Protruding objects shall not reduce the clear width of an accessible route or maneuvering space.

Question 60

LEED -

Answer 60

Leadership in Energy and Environmental Design (LEED) is a program that offers certifications for green buildings.
The third-party verification program was created by the U.S. Green Building Council (USGBC) as a means for healthier, sustainable, environmentally friendly, more efficient, buildings, homes, and neighborhoods.
LEED supplies the guidelines for creating a green building. Using individual points-based rating systems that differ by project type, building projects can achieve Certified, Silver, Gold, or Platinum statuses.
Project types can include new building design and construction, building operations and maintenance, interior design and construction, homes, and neighborhood development.
For each project type, LEED has a list of credits with specific requirements regarding anything from building materials to bicycle storage. Points are awarded based on the degree to which the requirements are met. There are several credits that include lighting as a means to a greener building.
The following LEED credits relate to lighting for new construction:
1. SSc8 – Light Pollution and Reduction
2. EAc1 – Optimize Energy Performance
3. EAp2 – Minimum Energy Performance
4. EQc6.1 – Controllability of Systems – Lighting

Question 61

Nationally Recognized Testing Laboratory Program (US Dept. Labor)

Answer 61

A Nationally Recognized Testing Laboratory (NRTL) is an independent laboratory recognized by the Occupational Safety and Health Administration (OSHA) to test products to applicable product safety standards.

Question 62

UL Listing

Answer 62

UL, formerly known as Underwriters Laboratory, is an agency that both develops product safety standards and performs product testing to see if they meet safety standards. Although UL develops many of these standards, other Nationally Recognized Testing Laboratories (NRTL) can also perform testing against the same UL standards. Because these alternative NRTLs offer lower pricing and faster turnaround times, many manufacturers often go down this route. You may come across other test agencies and certifications such as ETL and TUV.
Once a product is submitted for testing by a manufacturer, the product is tested against the UL standard for which the product is categorized under. 12V and 24V LED strips, for example, fall under the standard: UL2108, Low Voltage Lighting Systems. If it passes the test, the product is considered "listed" and will have the corresponding marking to distinguish this. For an LED strip, typically the UL or ETL logo (another testing company), along with the corresponding file number is printed directly onto the surface of the LED strip substrate.
UL approval (or other NRTL testing) is not legally required. It's only common because many large companies will not buy equipment that has not passed UL's safety tests. Many residential grade products are not listed.
CE marking is a certification mark that indicates conformity with health, safety, and environmental protection standards for products sold within the European Economic Area (EEA).

Question 63

Required Receptacles - Code Summary:

Answer 63

 For most areas of a house, receptacles must be no more than 12 feet apart and no more than 6 feet from a door or entryway – i.e, every point on almost all walls should be no farther than 6 horizontal feet from a receptacle. The wall spaces formed by fixed room dividers, such as freestanding counters, or railings, are included in the six-foot measurement.
 Receptacles installed in the floor within 18” of the wall may be used in place of wall-mounted receptacles. Receptacles installed in the floor must use a box-receptacle combination designed specifically for that purpose.
 Every hallway over 10 feet long must have at least one receptacle - other than this, hallways are exempt from the 6-foot rule.
 No outlets may be installed over an electric baseboard heater.
 Plugs which are located behind a stationary appliance such as a refrigerator or washing machine do not count when considering plug spacing.
 Any wall space that is 2 feet or more in width must have a receptacle.
 Every basement and garage must have at least one receptacle, and all must be GFI protected. At least one receptacle must be installed in each unfinished portion of a basement. This receptacle is in addition to any receptacles that may be installed for laundry or other specific purposes.
 One 20-amp branch circuit must be provided for the laundry. This circuit is limited to receptacles within the laundry room. No other outlets are permitted on this circuit.
 There must be at least two GFI plug on the outside of the house located near the front and back doors, and all exterior plugs must be GFI protected. Note: Outdoor outlets installed in wet locations shall have an enclosure that is weatherproof whether it is in use or not.
 An accessible 15- or 20-amp plug must be within 25 feet of all HVAC equipment.
 As a general rule you may have up to 10 receptacles on a single circuit, but this is a gray area which is subject to the discretion of the codes official.
 Dining room plugs must be on a separate circuit,
 At least one 20-amp circuit for bathroom receptacles must be supplied. Each bathroom must have its own GFI plug circuit with a plug near the wash basin, and no lights or other plugs or appliances on these circuits. Where a 20-ampere circuit supplies a single bathroom, outlets for other equipment within the same bathroom shall be permitted to be supplied in accordance with 210.23(A). This circuit shall NOT be used to supply a major fixture such as a whirlpool or hot tub!
 At least one 15 or 20-amp, 120 volt GFCI protected receptacle must be installed at an indoor spa or hot tub location - not closer than five feet from the inside wall of the unit and not more than ten feet away from it. Light fixtures, outlets and ceiling fans over spas and hot tubs shall be a minimum of 7’6” above the maximum water level. Note - pump motors and other spa related electrical equipment must remain accessible for service after all finishes are in place. Accessible does not include cutting holes in walls, or removing tile - plan ahead, and use common sense.
 Outdoors spa or hot tubs have the same requirements as a swimming pool. Check in section 680 of the NEC for those requirements.
 Note that all bedroom outlets must be protected by an arc-fault circuit interrupter listed to provide protection of the entire branch circuit. This includes wiring to the smoke detector outlets.210.12, NEC

Question 64

Kitchen Receptacles - Code Summary:

Answer 64

 In the kitchen and eating areas every counter space wider than 12 inches must have a GFI protected plug, in general all kitchen counter top plugs should be GFI protected. Countertop receptacles shall be installed so that no point along the wall is more than 24” measured horizontally from a receptacle outlet in that space. Peninsular bars and islands 12” or wider shall have at least one receptacle. Exception: Tennessee Code in dwelling unit’s section states, “The installation of receptacles for island counter spaces and peninsular counter spaces below the countertop shall be optional.
 At least two 20-ampere branch circuits are required to feed receptacle outlets for small appliance loads, including refrigeration equipment in the kitchen, pantry, breakfast room, and dining room. These circuits, whether two or more are used, shall NOT supply anything other than receptacles in these areas. Lighting outlets and built-in appliances such as garbage disposals, hood fans, dishwashers, and trash compactors are NOT permitted on these circuits.
 Kitchen counter top receptacles must be supplied by at least two small appliance branch circuits.
 Kitchen appliance and convenience receptacles must be on 20-amp breakers and wired with 12-gauge wire.

Question 65

Smoke Detectors - Code Summary:

Answer 65

 There must be a 120-volt with battery backup smoke detector on the ceiling, or on the wall close to the ceiling in the area outside of every bedroom, and inside of each bedroom. All smoke detectors must be tied together so that if one goes off they all do. Smoke detectors must be protected by an arc fault breaker. When you are roughing in for smoke detectors daisy-chain them with 14-3 WG and the extra (red) wire will interconnect the system.
 Note that all bedroom outlets must be protected by an arc-fault circuit interrupter listed to provide protection of the entire branch circuit. This includes wiring to the smoke detector outlets.210.12, NEC

Question 66

An ELECTRICAL PLAN

Answer 66

shows everything that is installed and connected electrically on top of a “typical Floor Plan”.
It usually doesn’t show the specific wiring, cable or conduit layout but should include: telephone, computer connectivity, security systems, TV connectivity, including satellite or aerial point, home automation, sound systems, intercom, electric gates, external lighting, air conditioning, Photo Voltaic (solar) panel points and related connections, heat pumps, automated irrigation and of course, lighting, switching and outlets.

Question 67

A REFLECTED CEILING PLAN

Answer 67

shows everything on the ceiling: grid, lights, HVAC supplies and returns, and sprinkler heads.
See Next Page for more details – sometimes when you have so major ceiling details, you can use only the Electrical Plan.

A reflected ceiling plan (RCP) is a drawing that shows which shows the items are located on/in the ceiling of a room or space – Lighting, Visible Mechanical Features and Ceiling Forms. It is referred to as a reflected ceiling plan since it is drawn to display a view of the ceiling as if it was reflected onto a mirror on the floor.
An RCP can include items below the ceiling – but sometimes it is best to simplify them to reduce confusion by:
 Using dotted lines for furniture and anything movable (this allows you to relate your lighting design to the furnishings
 Or remove all objects from the room for better clarity on the wiring layout – only include built-ins.
It should show:
 The construction of the ceiling (gypsum board., acoustical tile, etc.)
 A specification and/or finish (paint, stucco, etc.) of the ceiling material
 The height of the ceiling above the finished floor (A.F.F.)
 Dimensions (with enough detail to allow the contractors to build only using your drawings)
 Dimensions should include center lines and reference points for specific locations of fixtures.
 A legend explaining the symbols on the RCP
 An explanation of any ceiling features such as bulkheads, soffits,
 raised or vaulted areas, trim or decorative applications
 Section symbols to further explain the construction of any ceiling features
Special features you should include (specifically for lighting design):
 Speakers from a stereo or other communication device
 Emergency lighting & exit signs
 Security cameras or domes
 Smoke or fire alarm devices

Question 68

A LIGHTING PLAN

Answer 68

usually entails all the design elements to bring light into a space: elevations, plans, detailed, specs.
 Part of the LIGHTING PLAN that “interior designer’s” create, is a CAD drawn set of plans similar to Electrical Plans.
 This subset focuses primarily on LIGHTING and does not include things such as panels, distribution, and other non-lighting appliances or installations that you might find on a specific Electrical Plan. It can, but for smaller projects, you typically focus on one or two spaces/rooms and show the lighting and electrical connections only.
 LIGHTING PLANS also show Furniture and the relationship between the furniture and lighting locations.

Question 69

Why do we need both ELECTRICAL PLANS and REFLECTED CEILING PLANS?

Answer 69

 When features exist in the ceiling of room or space, they cannot be easily shown on a standard floor plan.
 Standard floor plans assume a “cut line” at around 4’. Duct work, dropped ceilings, speakers or anything else, would be “cut out” from the floor plan drawing.
 RCP’s use the floor plan (as an outline) and “pretends” that the flooring is a mirror reflecting all ceiling features onto it.

Question 70

Outline of the LIGHTING DESIGN PROCESS:

Answer 70

see pg 97-99
 Step 1: Survey and Document Existing or New Space
 Step 2: Define Goals (Technical, Artistic, Budgetary and Schedule) with Client/Contractor Input
 Step 3: Technical Considerations – adequate light, meets code, functional
 Step 4: Artistic Design – decorative touch, uniqueness to the location and client, adjustable scenes
 Step 5: Documentation, Permitting, Installation, Tuning and Follow-up Survey

Question 71

OLDER EYE ISSUES

Answer 71

Have several issues because of the normal aging process. Older eyes:

1. Do not focus well after 40 (lenses harden)
2. Have cloudiness from cataracts (and the yellowness of cataracts absorbs more blue light)
3. Require more light for more visual perception (by age 80 you need 6 times more light than at age 20)
4. Your corneas become opaquer and scatter light (making it hard to recognize objects).
5. And lastly your eyes can’t adjust as fast due to weakened ciliary muscles.

Question 72

How to Design for Elder Eyes?

Answer 72

1. Increase overall light levels (but check wattage of lamps – do not exceed, add lamps and use sunlight).
2. Lighten wall color (and use light matte finish to avoid glare).
3. Avoid recessed lights as they cause shadows and occasional glare.
4. Add dimmers so users can adjust to the level that’s comfortable.
5. Use adequate shades to avoid direct view of source. Reduces shiny surfaces that cause glare.
6. Keep light levels even throughout and incorporate task lighting to provide extra boost.
7. Ensure plenty of light in safety areas (stairs, porches, kitchen, bathrooms, garages) and ensure switches are accessible.

Question 73

Architectural Lighting

Answer 73

The three most common forms of architectural lighting are cove, soffit and valance; all three are integrated into the room’s structure. Cove lighting is located in a ledge, shelf or recess high up on a wall, and the light is bounced toward the ceiling or upper wall. Soffit lighting is located in a soffit or cornice near the ceiling, and the light radiates downward, washing the wall with light. Valance lighting is located in a wood, metal or glass valance (horizontal shield) mounted above a window or high on the wall, and the light bounces both upward and downward. The technique of bouncing light off walls and ceilings is known as indirect lighting, which is favored by many lighting professionals because indirect lighting minimizes shadows and glare. Architectural lighting is most often used as ambient lighting.

Question 74

Recessed -

Answer 74

Installed above the ceiling, this type of lighting has an opening that is flush with the ceiling. Recessed lights have to main options NON-IC and IC rated. Non-IC rated fixtures cannot come into contact with insulation (common in many ceilings) and are generally cheaper than IC rated. IC rated fixtures have thermal protection to avoid problems with excessive heat buildup. Recessed lighting sends a relatively narrow band of light in one direction; it can be used to provide ambient, task or accent lighting.

Question 75

Track -

Answer 75

Mounted or suspended from the ceiling, track lighting consists of a linear housing containing several heads that can be positioned anywhere along a track; the direction of the heads is adjustable also. Track lighting is often used for task or accent lighting. They come in line and low voltage. Low voltage heads usually require specialized dimmers.

Question 76

Under-cabinet -

Answer 76

Mounted under kitchen cabinets, this type of lighting can be linear or a single puck-shaped fixture (which are in decline). Under-cabinet lighting is extremely popular as task lighting in a kitchen. It is also not easy to properly design.

Question 77

Pendant -

Answer 77

Suspended from the ceiling, a pendant light directs its light down, typically over a table or kitchen island. A pendant can enhance the decorative style of a room. Pendants can provide ambient or task lighting with a single lamp.

Question 78

Chandeliers -

Answer 78

Suspended from the ceiling, chandeliers direct their light upward, typically over a table. They can enhance the decorative style of a room. Chandeliers provide ambient lighting. They are usually heavier with multiple lamps and require specialized junction boxes design for heavy objects.

Question 79

Ceiling -

Answer 79

This type of fixture is mounted directly to the ceiling (flush) and has a glass or plastic shade concealing the light bulb. Ceiling fixtures have been common in homes for nearly a hundred years, often providing all the ambient light in a room.

Question 80

Sconces -

Answer 80

Surface-mounted to the wall, sconces can direct light upwards or downwards, and their covers or shades can add a stylistic touch to a room. Wall sconces provide ambient or task lighting. In traffic areas restrict their protrusion into the walkway.

Question 81

Desk, Floor & Table Lamps -

Answer 81

Made in a wide range of sizes and styles, lamps are extremely versatile and portable sources of light in a room. Most lamps direct light downward, with the exception of a torchiere, which is a floor lamp that directs its light upward. Lamps are often used as task lights, particularly for reading, but can also provide ambient light.

Question 82

CALCULATING LIGHTING EFFECTS GRAPHICALLY:

Answer 82

The most common calculation is used to find the coverage area that a recessed can produces on a surface at distance away from the ceiling. In the example below, a = 8’ for an 8’ ceiling. We know from the lamp package that the lamp beam angle is 30 degrees and therefore the Beta angle is 15 degrees. The resulting b distance is 2.1436 feet. We can double that to know the coverage of the entire beam width = 4.2872 feet at the floor level. To have full coverage of the floor we need a can spacing of at least 4’. This spacing will show light and dark undulations. To ensure full and EVEN coverage you need to move them closer so that the 50% points of the cone of light overlap (and add to 100%). (Manufacturer’s photometry information will tell you the 50% point)
 If you want to calculate the beam coverage on a table top or countertop just substitute a = _____’ for the new height. This can also be used with reflectors for soffits, coves, valance, etc.

Question 83

SIMULATING LIGHTING EFFECTS GRAPHICALLY:

Answer 83

One popular method of communicating light patterns is to overlay on elevations or cross-sections, a gradient pattern in the shape and direction of light being emitted. The pattern should be full brightness or saturation near the source and fade to a lower level right before it falls onto a surface. If you want, you can add light levels at representative points (through calculations). Use more than one color when you have more than one source overlapping.

Question 84

Living Space Lighting Concepts:

Answer 84

In addition to standard Title24/Code requirements, you should be remember the following:

1. Modulated light is always more interesting than completely even illumination.
2. Don’t mix various sources/CRI/Color temps within eyesight (no blue casts mixed with yellow casts)
   a. This is also important for adjacent spaces (Kitchen, Bath etc.).
3. Design the illumination to put light where you want it rather than follow rules or grids.
4. Place recessed cans according to the ceiling height, beam width/angle and desired overlap
   a. When using recessed lights, many people create a grid and lay out cans on a regular basis.
   b. This doesn’t put light where you need – adjust the grid to account for furniture and for desired overlap of light intensity (50% overlaps for even – no overlap for dramatic light/dark areas).
   c. There are various recessed can trims that can cut off part of the light, can aim it or focus it as well.
   d. Trims can be another way to coordinate finishes in a room. Standard matte white blends in with white ceilings, whereas metallic or colored trims offer additional “designer looks”.
5. Architectural and accent lighting (hidden) is usually more “high end” and interesting than traditional table/floor lamps.
6. If unsure of future furniture or artwork changes, you can use variations of track or cable lighting to provide options.
7. Most likely you will use a combination of installed lighting and portable lighting.
   a. Consider how the lighting scheme will change if portable lighting is removed or moved.
   b. Consider how you can effectively light a space with installed lighting and supplement with portable – future proofing the space.
8. Consider aging eyes and how you can think ahead in your design.
9. In living spaces – you might also have a media space with additional power requirements, connections to the internet or cable, battery backup systems and other low voltage requirements. Knowing the location and placement of the media area will allow you to design ahead to be assured that there is sufficient infrastructure available.
10. Lastly – living spaces can range from very bright to very dim (from party to watching a movie). To layering and controlling light will be crucial to accommodate various functions.

Question 85

Kitchen Lighting Concept

Answer 85

The kitchen uses the most electricity of any of the residential rooms (excluding HVAC)
In addition to standard Title24/Code requirements, remember the following:
1. Under cabinet lighting – Goal: wash wall with light, evenly illuminate counter top.
a. Avoid specular reflection of lamping in dark, polished counter tops (use diffusers)
b. Avoid over brightening the backsplash wall (move source further away from wall – more light on counter)
c. Check CRI and Color Temp of source and match to other sources in room – LED light sources for strips are usually different sources than are in discrete lamps. If you purchase from the same manufacturer they should match.
d. Move light near front of cabinet and aim down and back to wall. Using part of the wall as a reflector can spread and diffuse light best. Many times, people aim the light in the wrong direction.
e. Add front and rear source if needed to give additional illumination – counter top backsplash colors can necessitate additional light if very dark and matte.
f. Add outlet strips under back of cabinet to avoid outlets in the backsplash (see code).
g. Add continuous lighting if possible (no dark spots). The biggest dark spot is under a good or microwave. If possible ensure that the light available from either is like that of the under-cabinet lighting.
h. If under cabinet lights are visible, add a facia at the front edge of the cabinets to hide.
i. If your kitchen is at a higher elevation than living or dining spaces, you may need additional diffusion to hide the lights from lower elevations.
2. Task lighting (pendants or recessed spots)
a. Ensure the lumen output and the beam angle evenly illuminate the counter (no puddles). Overlap at the 50% point.
b. Too narrow: ring of light on counter, too wide: spills onto flooring wasting light that should be covered by ambient.
3. Ambient lighting (usually through ceiling mount fixture or recessed cans)
a. Cans – don’t place in center of room, you will create shadows against people standing in front of counters.
b. Cans – add enough to avoid strong shadows and don’t place close to cabinets creating light scallops.
c. Ceiling mount – one per 20-25sq feet for even coverage.
4. Ensure the lighting you select will not degrade by the heat, moisture and airborne particulates specific to kitchens.
a. Decorative pendants particularly will accumulate fine oils and collect dust.
5. Coordinate metallic finishes of the luminaires with those of your appliances.
6. Consider aging eyes and how you can think ahead in your design.

Question 86

Bath Lighting Concept

Answer 86

In addition to standard Title24/Code requirements, you remember the following:

1. No hanging cords or pendants within 3’ horizontally and 8’ vertically from the top of the bathtub rim or shower threshold.
2. Fixtures within the tub/shower footprint must be marked for damp locations (or wet if subject to shower spray)
3. Need at least one wide horizontal linear or two vertical sconce/pendant fixtures for even facial illumination.
   a. CRI is critical for this fixture – and color temp should lean towards the warm side but not be too “red”.
   b. Ensure that you don’t have one spot source which creates unflattering shadows under the chin, nose and eyes.
   c. Over any mirror in any bath, avoid a recessed light directly over the sink area.
4. If recessed lighting is used, avoid shadows (two in shower/bath, one over the toilet centered on the front seat rim)
5. Two or three tier lighting is preferred:
   a. One moderate light best for transition from night to morning.
   b. One full brightness best for cleaning or morning routine after adjusting to light levels.
   c. One dim for night lighting (can be integrated into GFCI outlets).
6. With mirrors, metal and glass surfaces as well as reflective tile, watch for sources of specular reflection and glare.
   a. Use of diffuse sources or point sources with diffusion even out light in the space.
   b. When designing consider reflections at various points in the room – especially those while using the toilet.
7. In bathrooms, you have exposed metal on faucets, towel bars etc. Coordinate these metallic finishes with those of the luminaires so you don’t have Chrome Faucets mixed with Brushed Nickel Sconces.
8. Consider aging eyes and how you can think ahead in your design.
9. Bathrooms require vent fans that can have lighting incorporated within – again coordinate the CRI and color temp with other fixtures.
10. Night Lights provide a useful function in the bathroom. Many night lights incorporate a sensor that reduces their intensity or shuts them off if sufficient light is available (from artificial or natural light). Most GFCI outlets can be purchased with LED lights. If you find that the location of the GFCI doesn’t properly illuminate the floor, you can add an outlet or a dedicated night light on a wall in an appropriate location. Toe kick lighting for the cabinetry is also an option.

Question 87

Exit signage

Answer 87

An exit sign is a device in a public facility (such as a building, aircraft or boat) denoting the location of the closest emergency exit in case of fire or other emergency. Most relevant codes (fire, building, health or safety) require exit signs to be permanently lit.

Question 88

Troffer Lights -

Answer 88

A troffer is a rectangular light fixture that fits into a modular dropped ceiling grid (i.e. 2’ by 2’ or 2’ by 4’). Troffer fixtures have typically been designed to accommodate standard fluorescent lamps (T12, T8, or T5), but are now often designed with integral LED sources. Troffers are typically recessed sitting above the ceiling grid, but are also available in surface mount ‘boxes’.

Question 89

SELECTION OF LUMINAIRE BASED ON “Quality”

Answer 89

1. Price is always a great indicator.
2. Use reputable suppliers, recommendations from showroom, advice from contractors.
3. Use suppliers who specialize in lighting only.
4. Read reviews when available. Most written reviews outline negative issues – read carefully.
   a. Ordering difficulties – delays, showing available when backordered, extra costs.
   b. Installation difficulties – missing parts, broken parts, lamping not included when indicated.
   c. Incorrect specifications – tear sheet’s that contain wrong information.
   d. People ordered the wrong thing – people complain even though it is their mistake.
5. Understand your own requirements in terms of light output, size of fixture and style.
6. Inspect the luminaire in person if possible. Notice:
   a. Weight – if you can pick it up, the heavier it is the more material used, the more stable and solid it will be.
   b. Turn knobs/dials/switches. They should not feel flimsy but have good positive actions.
   c. Armatures and any sheet metal should be solid, not flimsy or bend easy. A swing arm should swing – not bend up and down as well.
   d. Notice long poles that are one piece vs. smaller segments (useful for shipping). More pieces can break or bend.
   e. Notice the electrical cord quality, color and style. No switches on the cord itself (cheap and prone to break).
   f. Notice how easy it is to re-lamp or modify the lamping type if available.
7. Do not purchase a luminaire that doesn’t include information on lamping source, how many lumens it outputs or CRI – especially if LED (LED suppliers are notorious for not including any information – especially on decorative lighting).
8. Beware of products made outside of the USA and that are not UL listed or certified.
9. Beware of NEW products, again especially made outside the country. Without a history of operation, you may prefer proven reputations.
10. Beware of knockoffs. There are knock offs of the Louis Poulsen Artichoke lamp. Real ones start at $35k. Lamps Plus knockoffs start at $200.
    a. Knockoffs are usually of inferior quality, have poorer lamping, are not warranted and are not supportive of designers.
11. Overall – use your eyes and hands to inspect a luminaire. If need be – visit inexpensive stores for comparison (IKEA) or home centers (which are usually more functional that beautiful). Practice!

Question 90

SELECTION OF LUMINAIRE BASED ON “Type of Light Output”

Answer 90

1. Point Sources
   a. spherical (hanging lamp in center of room) – provides broad even illumination – with harsh shadows
   b. Shielded (fully or partially encased lamp) - directional broad lighting – shadows less harsh
   c. Reflector usually MR or PAR Parabolic Aluminized Reflector (PAR) – Can provide spot, oval, parabolic shapes – either even or fading
   d. Beam projector w/ iris, shutters, baffles, grills (mostly for effects) – special effects to specifically light objects or areas – more theatrical
   e. Broadened point source – CFL, frosted lamp, LED (depending on type) – like point source with shielding (shade)
2. Broad Flat Sources
   a. LED backlit panels
   b. Troffers (rectangular light in a modular ceiling 2x2 or 2x4) with diffusers – most even illumination, few distinct shadows
3. Linear Sources
   a. Fluorescent tubes, Cold Cathode tubes, neon
   b. Linear LED strips
4. Circular
   a. Circular Fluorescent tubes
   b. Custom fixtures – particularly pendants
5. Bounce or Indirect Light
   a. Any that reflects of other surfaces using those surfaces as the primary direction of illumination – the surface characteristics (color, smoothness, material) determine the quality and quantity of bounce lighting – as well as the does the source.
6. Diffuser or No Diffuser
   a. Diffusers spread or diffuse light – softening it, reducing harsh shadows, minimizing glare, reducing contrast and they can enhance features (faces, architectural features).
   b. Diffusers allow a variety of sources to be used behind it. Thus, you achieve the same effect with different lamping. LEDS or T5/8 behind a broad diffuser looks like a flat panel of light and provide a uniform field of light.
   c. Not using a diffuser gives better specular reflections – makes glossy surfaces more interesting, provides more contrast and drama.
   d. A combination of diffuse and direct light can create even more dramatic effects. A wall sconce with a shade that is open and closed on the bottom provides unique patterns of light.

Question 91

Custom Fixture Warning

Answer 91

As with any luminaire design and installation, safety should be your priority. In many cases, heat build up (due to overcurrent, improper ventilation or improper heat sinking) will be the cause of lamping failure or degradation or worst-case, fire.