Chapters 9-14
Most large commercial building use two voltages: 480Y/277 volts and ____ / 120 volts
208Y
A washer dryer is rated 4000 VA at 208Y/120 volts single phase. the overcurrent protective device must be rated at least _____ amperes
25
For systems voltages of 0 to 150 volts to ground, the minimum depth of working space is ___ ft under all three working space conditions
3
Water heaters are available for commercial occupancies in many sizes and voltages, and for both single and _____ supply
3-phase
Even though multipair conductors are no longer used extensively in telephone installations, the size of the conduit should be trade size _____ or longer
3/4
NEC 408.36(A) stipulates that if the the panelboard contains snap switches with a rating of ____ amperes or less, the panelboard overcurrent is not permitted to exceed 200 amperes
30
Unused openings in panelboards and switches should be
Closed
In the insurance office example in this chapter, the reception area has an ___ to provide a different "look" for the clients.
Combination lighting system
In the insurance office example in this chapter, a separate, insulated grounding conductor is installed with the feeder circuit and is connected to the neutral conductor at the service point. This grounding systems reduces, if not eliminates, the ___ that often is present in the conventional grounding system.
Electromagnetic interference
The ____ program includes such things as replacing old style magnetic ballasts with high efficiency electronic ballasts, controlling lighting with timer and occupation sensors, and replacing low efficiency appliances with high efficiency appliances
Energy star
___ is the amount of light received in a unit of time on a unit area at a unit distance from a point source of one candela
Lumen
With a " ____ " elevator, the entire elevator lifting mechanism is located in the elevator shaft or on the wall.
Machine-room-less
____ lamps have the lowest efficacy of the HID family, which ranges from 30 lumens per watt for the smaller wattage lamps to 65 lumens per watt for the larger wattage lamps
Mercury vapor
___ are available in separate units, which can be used to provide protection on any type of sensitive equipment, such as computers and printers
Surge Protectors
A Toxicity Characteristic Leaching Procedure rating means that the lamp has passed ____ tests regarding the toxicity of the lamp
UL
The covers for multicover outlet assemblies are available in steel, _____, and PVC with vinyl laminates of different colors and wood veneers such as maple, cherry, mahogany, and oak.
aluminum
In a dual duct system, the junction box is constructed so that the power and the communication systems are
always separated from each other
The photocell control device consists of a light sensitive cell and an ___ that increases the cell until it is sufficient to operate a relay that controls the light
amplifier
Floor boxes, either metallic or nonmetallic, can be wired using
any suitable raceway
In an inducted circuit with an uncorrected power factor of 40 percent to 60 percent, the power factor can be corrected to within 5 percent of unity by the addition of an
capacitor
Three-phase circuits results in a smaller____ than if a 1-phase circuit were installed
circuit
In the first phase of the installation of a telephone system in a commercial building, the _____ will install an empty conduit system according tp specifications for the commercial building and in the locations indicated on the working drawings
electrical contractor
For a fluorescent lamp, the inside of the tube is coated with a phosphor ( a fluorescing material ), the air is evacuated, and inert gas plus a small quantity of ____ is released into the tube
mercury
The circuit directory gives the ___ for each circuit in a wording that would be clear for "nonelectrical" people to decipher and identify the circuit number for luminaires, receptacles, appliances, or equipment
purpose of use
When connecting receptacles in a multioutlet assembly, the ____ must be continuous so that the removal of a devices will not interrupt continuity
raceways
GFCI protection can be attained using GFCI circuit breakers or GFCI ____
receptacles
The reasoning for identifying the system voltage and phases is
safety
The _____ is defined in NEC Article 100 as the point of connection between the facilities of the serving utility and the premises wiring
service point
Instant start lamps require single pin bases and are generally called
slimline lamps
LED lighting could be called "_____" lighting
solid-state
NEC 250.64(C) states that grounding electrode conductors generally are not permitted to be ____
spliced
A fluorescent lamp with a 30 in its nomenclature indicates it produces light with a color temperature of ___ K, which would provide good rendition to warm colors
3000
In the water heater circuit example in this chapter, the minimum size conductor if all terminals are rated 75 degrees or higher, is awg as the allowable ampacity in NEC 310.16(B)(16) is 85 amperes
4
A washer dryer rated for 4000 VA at 208Y/120 volts single phase must have a branch circuit ampacity of at least _____ amperes
40
NEC 230.17 permits not more than ___ disconnects as the building disconnecting means
6
Working space height is required to not be less than ____ ft.
6.5
An allowance of _______ volt amperes is made for the installation of telephone equipment to provide the power required to operate the special switching equipment for the telephones used by tenants in a commercial building
600
In the boiler heating circuit in the chapter example, the main lugs connect to two ___ kemil-per-phase phase conductors run to an 800- ampere switch
600
The heat sensor in an electrically heated boiler is adjusted so that it closes when outside temperature falls below set point, usually ____ degrees Fahrenheit
65
____ is the ability of the lamp to portray objects as normally as possible
A lumen
_____ are similar to surface raceways and are designed to hold both conductors and devices
Multioutlet assemblies
Utilities make up the connections on the line side and load side of their transformers according to the requirements
NESC
____ for multioutlet assembles are available with GFCI, isolated grounded, and surge suppression features.
Receptacles
NEC 110.16 has a requirement for placing a notice on certain equipment to warn qualified persons of the serious hazard of _____ flash events
arc
In a communications system, the inside conduit drops ________.
are always grounded
On lighting controlled by timers, an ___ feature is extremely desirable because it provides sunset on and sunrise off that change automatically day by day as the sunrise and sunset times change every day.
astronomic
In the commercial building example of this chapter, the owner may choose to install an electrically heated ____ to supply heat to all areas
boiler
According to NEC 422.31(B), having a disconnect switch in sight is required if a ___ is not readily accessible
circuit breaker
NEC 422.13 requires that the branch circuit for a storage type electric water heater with a capacity of 120 gallons (450 L) or less is considered to be a ______ load
continuous
Panelboard ratings are determined by the ___ capacity of the internal main bus
current-carrying
Fluorescent lamps can be operated on a ____ circuit if the proper ballast is used. A ballast for this type of system contains a current-limiting resistor that provides an inductive kick to start the lamp
dc
The sump pump motor is protected by a manual starter and is controlled by a _____ switch
float
_____ occur when a ungrounded "hot" conductor comes in contact with a grounded surface or grounded equipment
ground fault
Often a feeder serves two or more panelboards, in which case either a _____ or wireway is installed or the feeder connects to the first panelboard and then is extended to the others
junction box
Because a small opening and limited space, _____ are used in communications systems rather than the standard conduit fitting.
junction boxes
Conductors to be installed in raceways may be spliced at ____ or within the raceway if the cover of the raceway is removable
junction boxes
The lower (or shorter) the ____ of the grounding path, the greater the ground fault current
length
In general, panelboards are constructed so the ___ run vertically for nearly the height of the panelboard
main feed busbars
One type of sump pump that is available commercially has a start-stop operation due to water pressure against a ____, which in turn pushes against a small integral switch within the submersible pump
neoprene gasket
In the computer room circuits in the chapter example, three separate neutral conductors are installed to reduce the possibility of a conductor over heating from ___ currents
nonlinear
With an electrically heated boiler, a heat sensor plus a remote bulb is mounted so that the bulb is
on the outside of the building
For electrical equipment not considered large, at least _____ entrances of sufficient area is required to provide access to and egress from the working space
one
The ____ connection scheme has the advantage of being be able to provide 3-phase or either 3-phase and single phase power using only two transformers
open delta
The circuit to the hot water circulating pump in the chapter example will be supplied from the ____ so that the water will continue to circulate if the utility power fails
optional standby power panel
Separate feeder are to be ran from the main service equipment to each of the areas of the commercial building, each feeder will terminate in a ___ , which generally will be installed in the area to be installed
panelboard
In lamp designations, PAR means ___
parabolic reflector
GFPE monitors are designed to sense _____ faults only.
phase-to-ground
The fighting circuits that are considered to be the owners responsibility can be divided into six groups according to the method used to control the circuit, including those under
photocell control
The ____ is an example of equipment that is operated by an automatic control system
sump pump
The _____ feature of a receptacle provides protection from lighting and other severe electrical surges that may occur in the electrical system
surge protection
In this country and throughout the world, ___ is the common reference point in all electrical systems
the earth
The combined size of the conductors, splices, and taps should not fill more than _____ percent of the raceway at the point where the splices and taps occur
75
All working spaces must allow for the opening of equipment doors hinged panel to at least a ___ degree position
90
In a commercial building, it is the _____ responsibility to provide power for the elevator, illuminations for the public areas such as hallways, stairways, and public toilet rooms, and heat for the common areas of the building.
Owner's
The building occupants will each have a ______ located within their particular area
heating thermostat
Today's liquid filled transformers have their winding immersed in highly refined mineral oil (combustible), silicone fluid, edible seed oil dielectric coolant, or other acceptable non toxic liquids that have _____ properties
high dielectric
The temperature of an electrical arc, such as might occur on a 480/277-volt solidly grounded, wye-connected system, are
hotter than the surface of the sun
The luminaries installed for the raceway for the second floor and hallways of a commercial building are examples in this chapter are ____ when the building is occupied because those spaces have no windows
in continuous operation
In the plans for the commercial building in the chapter example, high efficiency energy saving fluorescent lighting and LED lighting is used. Very few ___ lamps are used
incandescent
In the computer room example in this chapter, the grounding terminal of each of the special receptacles is connected to an ____
installed equipment grounding conductor
Some floor boxes must be installed to the correct height by adjusting the ___ before the concrete is poured
leveling screws
Dry-type transformers are widely used because they are ____ than comparably rated liquid filled transformers
light in weight
The two basic methods of metering are primary high-voltage metering and ____
low voltage metering
The light producing element in the incandescent lamp is a ______ wires called the filament.
tungsten
In the insurance office example in this chapter, a special raceway is installed in the _____. This raceway provides for both electrical power and communications.
two exterior walls
Two methods can be used to provide floor outlets: (1) installing ____ raceway or (2) installing floor boxes
underfloor
When tabulating materials, take special note of long runs of raceway or cable and determine weather ___ is a problem. This can mean an increase in conductor raceway size
voltage drop
Lamps are usually selected according to their
wattage rating
Conductors for 480Y/277 volt system are generally brown, orange, and for the ungrounded conductors and gray for the grounded conductor
yellow
