MEEB Ch. 25-32 Study Guide
Increases in PV module efficiency, new materials, and other initiatives have brought the cost of PV (per peak Watt) to about
$0.25-$0.50
Standard escalators have a tread width of
(a) 24 inches (0.6 m) (b) 40 inches (1.0 m) (c) both a and b
Which of the following is not a valid electrical switch class?
1.5 kV
A designer seeking to avoid resentment and confusion among building occupants would design a separation between escalators in a crisscross walk-around of no more than
10 ft (3 m)
A 32-in. (810-mm) escalator with a maximum rise of 30 ft (9.1 m) would require a ___ motor.
10 hp (7.5 kW)
Elevators can account for as much as ______ of a mid-rise (25-story) building's construction cost
10%
Which of the following volt-amperage values would be logical for a 15-A residential circuit operating at 25% expansion?
1150 V-A
Today's commercial two-layer PV arrays have a maximum insolation-to-electric energy conversion rate of:
12%
For the purpose of predicting overall building electrical load, continuous loads should be calculated at ___ of their actual value
125%
What is the maximum permissible operating speed of a 3-to-5-degree angle moving ramp with a level entrance?
180 fpm (0.9 m/s)
Because users will become annoyed at the long walk-around, it is not advisable to use the stacked parallel arrangement of escalators in an installation extending beyond ___ floors.
2
A load center pad-mounted unit substation would typically have a primary voltage range of
2.5-15 kV
Lighting tracks are generally rated at
20 A
Signal system riser closets should have a minimum net area of _______ and a minimum clear wall of ________ for cabinet mounting.
20 ft2 (2 m2); 5 ft (1.5 m)
Gearless traction machines are usually used for passenger service, with car capacities between
2000 lb (907 kg) and 4000 lb (1814 kg)
The best distribution system for a large, multistory building that principally uses fluorescent or HID lamps is:
277/480 V, 3-phase, 4-wire
A PV system battery is generally expected to supply all of an installation's electrical requirements for a period of ___ days of cloudy weather
3
All escalators in the United States are installed at an angle of ___ degrees from the horizontal
30
What is the carrying capacity of a single-lane moving walkway rated at 100 fpm (0.5 m/s)?
3000 passengers per hour
A tracking array can increase the insolation per PV module unit area by:
35% - 50%
The minimum ADA-permitted door opening for an elevator is
36 in. (0.9 m)
Which of the following would be a typical dimension of a single-phase uninterruptible power supply (UPS) unit?
36 in. x 12 in. x 36 in. (915 x 305 x 915 mm)
To protect against all types of weather conditions, one should specify an equipment enclosure of type
4
A clear wall space (width) of ____ is needed for the service entrance of a multiple-dwelling telephone system.
4 to 6 ft (1.2 to 1.8 m)
To completely allow passengers to simultaneously enter and exit an elevator doorway, an opening ___ wide may be necessary
48 in. (1.2 m)
A moving walk is defined as having an incline not exceeding ______, whereas a moving ramp has an incline limited to ______.
5%, 15%
A power utility will most likely find overhead transmission economically feasible for voltages greater than
5000 V
In commercial spaces, an electrical closet might be preferable to a stand-alone panelboard for a building of ___ or more stories.
6
Standard escalator installations have a maximum combined rise of
60 ft (18 m)
If a building's emergency power supply consists of batteries, the batteries must have a full-load capacity of
90 minutes
What facility type would require the greatest wiring system flexibility?
Research Laboratory
Which of the following is not a maxim for the safe grounding of a secondary wiring system?
The neutral wire must be color-coded yellow on any insulation color other than blue, along at least half the conductor length.
What is the primary disadvantage of an automatic instantaneous demand control system for electric power?
The system cannot readily adapt to varying load patterns.
Which of the following transmission line methods is the most expensive?
Type I burial
The advantage of using a contactor rather than a switch is that
a contactor can be remote controlled
According to Fig. 30.19ab , the designer of a machine shop that uses a punch press would want to install an industrial signal system that employed a device at least as loud as
a conventional horn
Direct current can be defined as a condition where
a flow of current takes place at a constant rate in the same direction around a circuit
Which of the following is not an advantage of a geared traction machine over a gearless machine?
a geared machine requires less maintenance
Which of the following would be a good location for an electrical closet?
a location where conduits can enter and leave the location vertically and horizontally
A 120/208-V single-phase, three-wire system would be used primarily to serve
a single-family residence or small commercial building
A direct-connected PV array might be used powering an application such as filling an elevated water tank because
a slow, interruptible fill rate does not adversely affect the water's usability
The primary difference in design for a stand-alone PV system and for a grid-connected system is that
a stand-alone system must provide the entire electric load, while a grid-connected system may provide part of the load
A "drawout" switchboard is
a type of switchboard that has circuit breakers mounted in a movable drawer
In a series circuit, voltages and resistances are
added
A conductor's current-carrying capacity is referred to as its
ampacity
An elevator's counterweight should be equal to the weight of:
an empty car plus 40% of the rated live load
Which of the following occupancy types exhibits the highest air-conditioning load?
auditorium
The acronym BIPV stands for:
building integrated photovoltaic
An "inverter" is a device that
changes direct-current to alternating-current
All of the following are advantages of hydraulic elevators over traction elevators, except
cheaper operating expenses
To avoid the risk of electric shock, it is recommended that appliance housings be grounded to a:
cold-water pipe
Use of AC cable is typically confined to
dry locations
Almost all indoor unit substations use ____ transformers.
dry-type
Devices that carry the description "energy management" have a primary function of controlling
energy use
The tilt angle of a PV array, to capture maximum insolation when the sun is lowest, should be:
equal to the site latitude plus 15 degrees
In the design procedure for wiring a building, one would compute panel loads before
feeder and protective equipment ratings are computed
In building communication systems, copper cabling is often replaced with the following cable type in applications with heavy data transmission or use of video systems
fiber optic cable
A "step-down" transformer
has a greater number of turns in its primary coil than its secondary coil
Which of the following is not a typical use of dc power?
high-voltage transmission lines
Light-emitting diode (LED) school clocks are best utilized:
in low-ambient light situations
Which type of interior wiring system is typically only used in industrial applications?
insulated cables in open raceways
Which of the following minimum standards does not fall under the definition of "open architecture," in building-automation system (BAS) terms?
integrate as much as possible with the building's structure
A single conductor of No. 8 AWG standard
is referred to as a "wire"
The advantage of using a cable bus over a busduct is that
it has a higher amperes-per-dollar first-cost
A busway or busduct is ideally used when ______.
it is necessary to carry large amounts of current
Which of the following is not a generally accepted guideline governing escalator design?
locate elevator and escalator access areas on the same landing so that passengers can make decisions between the two
The most popular form of exterior transformer installation for individual buildings is
mounted on a concrete pad
Which type of intrusion-detection system sensor is no longer used in new construction?
normally open contact
Hydraulic elevators currently use _______ as their system fluid
oil
Which of the following is not a typical escalator arrangement?
parallel helix
Lighting occupancy controls generally employ which type of detector:
passive infrared
In a typical building electrical power system wiring closet, dry-type transformers are typically placed between
plug-in busways and 120-V panelboards
In a transformer, ___ remains constant.
power capacity
The "ohm" is a unit of measurement for
resistance
Which of the following elevator drive control mechanisms is no longer employed?
rheostatic control of an ac traction motor
Which PV system battery type requires the least maintenance?
sealed
An elevator system using selective collective operation has the advantage of
shorter waiting periods
To accommodate a home office worker, master bedrooms should be provided with a minimum of
six duplex 15-A or 20-A receptacles connected to at least two different circuits
Which of the following is not an elevator control equipment type?
spin control
"Insolation" is best defined as
the amount of solar energy received by a given area, measured in Wh/m2
The unit of electric current is
the ampere
The use of nonflammable liquid coolants has largely been discontinued in transformers because
the coolants contain PCBs, which are banned in new installations
The current rating of an electrical service item is determined by
the maximum temperature at which its components can operate at full load
In a two-channel sound system, the preamp would be located between
the program selector and the distribution switch bank
Raceways have now become a major architectural consideration that must be addressed early in the design process because
the proliferation of computers and networking equipment require the distribution channels to be much wider than before
The overall load factor is
the ratio between the average and maximum power demands of a building
Which of the following is not a factor for determining the system requirements for a stand-alone PV array?
the reliability of the local electric grid
In a parallel circuit, current at each load depends upon
the resistance of each load
Remote-control signaling differs from automated signaling primarily in that:
the signal initiation in an automated system is non-manual
"Premise wiring" can be defined as:
the system of raceways, boxes and outlets dedicated to communication systems, excluding audio signals
Master stations in residential intercom systems differ from remote stations in that
they allow selective calling
Oil-insulated transformers can be expensive to install indoors because
they must be placed in a fire-resistant vaul
Which type of elevator drive control mechanism is best suited to buildings with a maximum rise of 250 ft (76 m) and a maximum car speed of 350 fpm (1.8 m/s)?
thyristor-controlled ac motor
In a two-level underfloor duct system, ducts are run near the center of a bay in a depressed-slab system
to avoid the steel in beams or joists near columns
A "ratchet" clause in a utility billing plan is disadvantageous for which type of user?
users with a low yearly load factor
Electrical energy cost is directly related to energy consumption, except in the case of
utility demand charges
Which of the following is not an accepted escalator fire-protection method?
ventilated combplates
The name given to the force driving electron flow between positive and negative terminals is
voltage
Which building electrical sub-system includes panelboards and circuit breakers?
wiring and raceways
Energy is the technical term for the more common expression
work
