Timed Exam 1 (electrical)

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What is the approximate diameter in inches of NO. 2 RHW wire. (Chapter 9 Table 5)

.412 inches

A wall space in a dwelling unit for purposes of outlet spacing shall be considered any unbroken space _______ feet or more in width including space measured around corners and unbroken along the floor line by doorways, fireplaces. 210.52 (A) (2)

2 ft

In rigid metal conduit or intermediate metal conduit, what is the minimum burial depth for wiring under streets, highways, roads, alleys, driveways, and parking lots. 300.5

24 inches

The dwelling has a floor area of 1500 sq ft exclusive of an unfinished cellar not adaptable for future use, unfinished attic, and open porches. It has two 20-A small appliance circuits, one 20-A laundry circuit, two 4-kW wall-mounted ovens, one 5.1-kW counter-mounted cooking unit, a 4.5-kW water heater, a 1.2-kW dishwasher, a 5-kW combination clothes washer and dryer, six 7-A, 230-V room air-conditioning units, and a 1.5-kW, 230-V permanently installed bathroom space heater. Assume wall-mounted ovens, counter-mounted cooking unit, water heater, dishwasher, and combination clothes washer and dryer kW ratings equivalent to kVA. Assuming the dwelling is feed by a 120/240-V, 3-wire, single-phase service, what is the total calculated load in VA and the minimum required service rating required. (Annex D, example D2 (b)

29,200 VA, 122 A

Up to three sets of _________ or two sets of 4-wire or 5-wire feeders shall be permitted to utilize a common neutral. 215.4

3-wire feeders

The distance between a cable or conductor entry and its exit from the box shall not be less than ______times the outside diameter, over sheath, of that cable or conductor. 314.71 (1)

36

What is the minimum bending radius in inches for 3/4" EMT using a Full Shoe bender. chapter 9, Table 2

4.5 inches (4 1/2)

What is the adjustment factor percentage for more than three current-carrying conductors in a raceway or cable if there are 21 current-carrying conductors in a 2 inch EMT. Table 310.15 B 3 a

45

A device or group of devices that serves to govern, in some predetermined manner, the electric power delivered to the apparatus to which it is connected. 100

Controller

A device, group of devices, or other means whereby the conductors of a circuit can be disconnected from their source of supply.

Disconnecting Means

Locations of lamps for outdoor lighting shall be below all energized conductors, transformers, or other electric utilization equipment, unless either of the following apply: 225.25

Equipment is controlled by a disconnecting means that can be locked in the open position OR clearances or other safeguards are provided for re-lamping operations.

A switch intended for use in general distribution and branch circuits, It is rated in amperes, and it is capable of interrupting its rated current and its rated voltage. 100

General-Use Switch

THHN insulation has what which characteristic trade name. Table 310.104

Heat-resistant thermoplastic

Paper insulated conductors typically have what outer covering: 310.13 Table 310.104 A

Lead Sheath

A compartment or chamber to which one or more air ducts are connected and that forms part of the air distribution system. 100

Plenum

The purpose of the National Electrical Code is the ___________ of persons and property from hazards arising from the use of electricity. 90

Practical Safeguard

The point of connection between the facilities of the serving utility and the premises wiring. 100

Service Point

Which of the following methods is not approved for the installation of service-entrance conductors. 230.43

Type NM cable

Conductors and cables in tunnels shall be located _________ and so placed or guarded to protect them from physical damage. 110.51 (C)

above the tunnel floor

FMC ________ connectors shall not be concealed. 348.42

angle

The normally non-current-carrying metal parts of all service enclosures shall be effectively ___________.

bonded together

Conductor sizes are expressed in American Wire Gage (AWG) or __________ . 110.6

circular mils

The connection of a grounding electrode conductor or bonding jumper to a grounding electrode shall be accessible except, an encased or buried connection in a __________, driven, or buried grounding electrode shall not be required to be accessible. (250.68 (A) Exception 1)

concrete-encased

All ________ of the same circuit and, where used, the grounded conductor and all equipment grounding conductors and bonding conductors shall be contained within the same raceway, auxiliary gutter, cable tray, cablebus assembly, trench, cable, or cord. Exceptions excluded. 300.3 (B)

conductors

Normally non-current-carrying conductive materials enclosing electrical conductors or equipment, or forming part of such equipment, shall be _________ so as to limit the voltage to ground on these materials. 250.4 (1)

connected to earth

The grounding electrode conductor shall be of ________ .

copper, aluminum, copper-clad aluminum

Each commercial building and each commercial occupancy accessible to pedestrians shall be provided with at least one outlet in an accessible location at each _________ to each tenant space for sign or outline lighting system use. 600.5

entrance

To prevent corrosion, raceways, cable trays, cablebus, auxiliary gutters, cable armor, boxes, cable sheathing, cabinets, elbows, couplings, fit-tings, supports, and support hardware shall be of materials suitable for the _________ in which they are to be installed. 300.6

environment

Overhead Service, where not in excess of 600 volts, nominal, shall follow minimum clearances measured from ______. 230.24

final grade

Flexible Metallic Tubing (FMT) can be used in which of the following places or conditions. 360.10

for system voltages of 1000 volts maximum

In the installation and uses of electric wiring and equipment in ducts, plenums, and other air-handling spaces, _________ shall be installed in ducts or shafts containing only such ducts, used for vapor removal or for ventilation of commercial-type cooking equipment. 300.22 (A)

no wiring systems of any type

Multi-conductor cables used for overhead service conductors shall be attached to buildings or other structures by fittings identified for use with service conductors. Open conductors shall be attached to fittings identified for use with service conductors or to noncombustible, ________ insulators securely attached to the building or other structure. 230.27

non-absorbant

The building or structure disconnecting means shall plainly indicate whether it is in the ___________ position. 225.38

open or closed

On a 4-wire, delta-connected system where the midpoint of one phase winding is grounded, only the conductor or busbar having the higher phase voltage to ground shall be durably and permanently marked by an outer finish that is _______ in color or by other effective means. 110.15

orange

Equipment intended to interrupt current at fault levels shall have an interrupting rating not less than nominal circuit ________ and the current that is available at the line terminals of the equipment.

voltage

For dwelling units, attached garages, and detached garages with electric power, at least one ___________ shall be installed to provide illumination on the exterior side of outdoor entrances or exits with grade level. 210.70 (1)

wall switch controlled lighting outlet

Continuity of the grounding path or the bonding connection to interior piping shall not relay on ____________. 250.53 D 1

water meters or filtering devices and similar equipment

Type MC cable shall not be used _______, unless identified for the use.

where exposed to direct sunlight

A multi-family dwelling has 40 dwelling units. Meters are in two banks of 20 each with individual feeders to each dwelling unit. One-half of the dwelling units are equipped with electric ranges not exceeding 12 kW each. Assume range kW rating equivalent to kVA rating in accordance with 220.55. Ohter half of ranges are gas ranges. Area of each dwelling unit is 840 sq ft Laundry facilities on premises are available to all tenants. Add no circuit to individual dwelling unit. Could you use 2 15 A circuits to handle the general lighting load? Annex D Example

yes

Does a pipe organ have any special grounding requirements? (250.3 additional ground/bond requirements / 650.5)

yes

Metric designator 41 is the same as trade size__________. Table 300.1 C

1 1/2

In both exposed and concealed locations, where a cable or raceway type wiring method is installed through bored holes in joist, rafters, or wood members, holes shall be bored so that the edge of the hole is not less than ______ inches from the nearest edge of the wood member. Where this distance cannot be maintained, the cable or raceway shall be protected from penetration by screws or nails by a steel plate or bushing, at least ______ inches thick, and of appropriate length and width installed to cover the area of the wiring. 300.4 A 1

1.25, .0625 (1 1/4, 1/16)

What is the minimum distance between bare metal parts, busbars, and so forth in a panel-board between live parts to ground where the voltage 240-V. Table 408.56

1/2 inch

For circuits supplying loads consisting of motor-operated utilization equipment that is fastened in place and has a motor larger than _____ hp in combination with other loads, the total calculated load shall be based on _____ percent of the largest motor load plus the sum of the other loads.

1/8 hp 125 %

Noncombustible surfaces that are broken or incomplete shall be repaired so there will be no gaps or open spaces greater than _________ inches at the edge of the cabinet or cutout box employing a flush-type cover. 312.4

1/8 inches

The point of attachment of the service-drop conductors to a building or other structure shall provide the minimum clearances and in no case shall this point of attachment be less than ________ feet above finished grade. 230.26

10 feet

A warehouse storage area uses mercury vapor lighting. What is the minimum lighting load in the warehouse area if it has 40,500 sq. ft. for storage. (Table 220.12 General lighting load by occupancy)

10,125 VA (40,500 x 1/4 = 10,125 VA)

In dwelling units the lighting demand factor of the first 3000 VA or less is ________ percent. table 220.42

100 %

Where the assembly, including the over-current devices protecting the feeder(s), is listed for operation at _______ percent of its rating, the allowable ampacity of the feeder conductors shall be permitted to be not less than the sum of the continuous load plus the noncontinuous load. 215.2 (A) exception 1

100%

LFMC shall be securely fastened in place by an approved means within ______ inches of each box, cabinet, conduit body, or other conduit termination and shall be supported and secured at intervals not to exceed ______ feet. Exceptions ignored. 350.30 (A)

12 inches 4 1/2 feet

Where a branch circuit supplies continuous loads or any combination of continuous and noncontinuous loads, the rating of the overcurrent device shall not be less than the noncontinuous load plus ______ percent of the continuous load. 210.20 A

125%

What is the maximum fill allowance for a 4 inch square box 2.125" deep (4 in. square = 4 x 4 x 2 1/8), for No. 12 copper conductors. Table 314.16 (B) & Table 314.16 (A)

13

What is the allowable ampacity for a NO. 14 fixture wire. table 402.5

17 amp

In circuits for control of irrigation and landscape lighting limited to not more than 30 volts and installed with type UF cable under minimum of 4-inch thick concrete exterior slab with no vehicular traffic and the slab extending not less than 6 inches beyond the underground installation, what is the minimum required burial depth. Table 300.5

6 inches

Service-entrance conductors to buildings or enclosures shall be installed and shall not be smaller than _______ AWG unless in multi-conductor cable. Multi-conductor cable shall not be smaller than _______ AWG. 230.202 A

6, 8

Over-current devices shall be readily accessible and shall be installed so that the center of the grip of the operation handle of the switch or circuit breaker, when in its highest position, is not more than 6 ft _____ inches above the floor or working platform. Exceptions ignored. 240.24 (A)

7 inches

The maximum current, in amperes, that a conductor can carry continuously under the conditions of use without exceeding its temperature rating. 100

Ampacity

A grounded metal enclosure containing factory-mounted bare or insulated conductors, which are usually copper or aluminum bars, rods, or tubes. 368.2 Definition

Busway

An assembly of a fuse support with either a fuse-holder, fuse carrier, or disconnecting blade. The fuse- holder or fuse carrier may include a conducting element (fuse link) or may act as the disconnecting blade by the inclusion of a non-fusible member. 100 definitions (cutout)

Cutout

Laundry Circuit Load. A load of not less than 1500 volt-amperes shall be included for each 2-wire laundry branch circuit installed, this load shall be permitted to be included with the _________ load and subjected tot he demand factors provided in Table 220.42 220.52 B

general lighting

Switches or circuit breakers shall not disconnect the ________ conductor of a circuit. Exceptions ignored. 404.2 B

grounded

Electrical Nonmetallic Tubing, ENT, may be used _________. Exceptions ignored. 362.10

in a two story building

Lighting track shall not be installed in the following locations. 410.151 A C

in storage battery rooms, in wet or damp locations, where likely to be subjected to physical damage, where concealed

Service conductors passing over a roof shall be securely supported by substantial structures. Where practicable, such supports shall be __________. 230.29

independent of the building

Which of the following shall not be used as grounding electrodes: 250.50

metal underground gas piping system and aluminum electrodes

Aluminum, copper-clad aluminum, or copper conductors of size 1/0 AWG and larger, comprising each phase, polarity, neutral, or grounded circuit conductor, shall be permitted to be connected in ___________ (electrically joined at both ends). Exceptions ignored. 310.10 A

parallel

A receptacle outlet shall be installed wherever flexible cords with attachment plugs are used, and where flexible cords are permitted to be permanently connected, receptacles shall be ________ for such cords. 210.52 - 210.63 (B)

permitted to be omitted

A box or conduit body shall not be required where a luminaire (fixture) is used as a __________. 300.15 (J)

raceway

Bends shall be made so that the tubing is not damaged and the internal diameter of the tubing is not effectively _________. 358.24

reduced

Circuit breakers shall be marked with their ampere rating in a manner that will be durable and visible after installation, the marking shall be permitted to be made visible by __________. 240.83 A

removal of a trim or cover

Conduits or raceways through which moisture may contact live parts shall be __________ . 300.5

sealed or plugged at either or both ends

Where cable is used, each cable shall be ________ to the cabinet, cutout box, or meter socket enclosure. Exceptions ignored. 312.5 C

secured

No small-appliance branch circuit shall ___________ . 210.52 (3)

serve more than one kitchen

Maximum Number of Disconnects, 2 or 3 single-pole switches or breakers capable of individual operation shall be permitted on multi-wire circuits, one pole for each ungrounded conductor, as one multi-pole disconnect, provided they are equipped with identified handle ties or a master handle to disconnect all ungrounded conductors with no more than ________ operations of the hand. 255.33 B

six

The disconnecting means for each supply shall consist of not more than _____ switches or _______ circuit breakers mounted in a single enclosure, in a group of separate enclosures, or in or on a switchboard. 225.33 A

six, six

Where outdoor lampholders are attached as pendants, the connections to the circuit wires shall be _________ . 225.24

staggered

A means shall be provided in each metal box for the connection of an equipment grounding conductor. The means shall be permitted to be a ________ or equivalent. 314.40 (D)

tapped hole

The entrance to all buildings, vaults, rooms, or enclosures containing exposed live parts or exposed conductors operating at over 600 volts, nominal, shall be kept locked unless such entrances are under _________. 110.34 (c)

the observation of a qualified person at all times

For circuits supplying lighting units that have ballasts, transformers, or auto-transformers, the calculated load shall be based on __________. 220.18 (B)

the total ampere ratings of such units and not on the total watts of the lamps

High-impedance grounded neutral systems in which a grounding impedance _______ ground-fault current to a low value shall be permitted for 3-phase AC systems of 480 volts to 1000 volts where certain conditions are met. 250.36

usually a resistor


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