Ch. 2 Mike Holt Study Guide

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c) a and b

120 V, single-phase, 15A and 20A brand circuits supplying outlets and devices installed in guest ____ of hotels and motels shall be protected by any of the means described in 210.12(A)(1) through (6). a. rooms b. suites c. a and b d. none of these

43

A demand factor of __ percent applies to a multifamily dwelling with ten units if the optional calculation method is used.

special permission

Additional services shall be permitted for a single building or other structure sufficiently large to make two or more services necessary if permitted by _______ __________.

6

An insulated grounded conductor __ AWG or smaller shall be identified by a continuous white or gray outer finish, or by three continuous white or gray stripes along its entire length on other than green insulation.

30A

For installations consisting of not more than two 2-wire brand circuits, the building disconnecting means shall have a rating of not less than ___.

180

For other than dwelling occupancies, banks, or office buildings, each receptacle outlet shall be calculated at not less than ____ VA.

d. all of these

For the purposes of 210.71, examples of rooms that are not meeting rooms include ____. a. auditoriums b. schoolrooms c. coffee shops d. all of these

d. a and b

Grounded electrical systems shall be connected to earth in a manner that will ____. a. limit voltages due to lightning, line surges, or unintentional contact with higher-voltage lines b. stabilize the voltage-to-ground during normal operation c. facilitate overcurrent device operation in case of ground faults d. a and b

6

Grounding electrode conductors __ AWG and larger that are not exposed to physical damage can be run along the surface of the building construction without metal covering or protecting.

d. any of these

Grounding electrode conductors of the wire type shall be ____. a. solid b. stranded c. insulated or bare d. any of these

5/8

Grounding electrodes of the rod type less than ___ in. in diameter shall be listed.

18 in

If a set of 120/240 V overhead feeder conductors terminates at a through-the-roof raceway or approved support, with not more than 6 ft. of these conductors, 4 ft horizontally, passing over the roof overhand, the minimum clearance above the roof for these conductors is not les than __ __.

shall

Lightning protection system ground terminals _____ be bonded to the building or structure grounding electrode system.

orange

On a three-phase, 4-wire, delta-connected service where the midpoint of one phase winding is grounded, the service conductor having the higher phase voltage-to-ground shall be durably and permanently marked by an outer finish that is ______ in color, or by any other effective means, at each termination or junction point.

c. a and b

Outside feeder tap conductors can be of unlimited length without overcurrent protection at the point they receive their supply if the tap conductors ____. a. are suitably protected from physical damage b. terminate at a single circuit breaker or a single set of fuses c. a and b d. none of these

18

Receptacle outlets in or on floors shall not be counted as part of the required number of receptacle outlets for dwelling unit wall spaces, unless they are located within __ in. of the wall.

d. a and b

Service-drop conductors shall have ____. a. sufficient ampacity to carry the load b. adequate mechanical strength c. a OR b d. a AND b

d. all of these

Service-entrance conductors can be spliced or tapped by clamped or bolted connections at any time as long as ____. a. the free ends of conductors are covered with an insulation that is equivalent to that of the conductors or with an insulation device identified for the purpose b. wire connectors or other splicing means installed on conductors that are burried in the earth are listed for direct burial c. no splice is made in a raceway d. all of these

d. none of these

The *Code* requires the installation of an equipment grounding conductor of the wire type in ____. a. rigid metal conduit (RMC) b. Intermediate metal conduit (IMC) c. Electrical metallic tubing (EMT) d. none of these

necessary

The conductors used to connect the surge protective device to the line or bus and to ground shall not be any longer than __________ and shall avoid unnecessary bends.

one- and two- family dwellings

The receptacle outlet required for indoor electrical service equipment shall not be required to be installed for ____ ___ ____ ______ __________.

Column A

To determine the feeder calculated load for ten 3 kW household cooking appliances, use ______ __ of Table 220.55.

True

True or False: When supplying a grounded system at a separate building or structure, an equipment grounding conductor shall be run with the supply conductors and connected to the building or structure disconnecting means and the the grounding electrodes.

True

True or False: Where fuses are used as the service overcurrent device, the disconnecting means shall be located ahead of the load side of the fuses in accordance with 230.91.

True

True or False: Where more than one concrete-encased electrode is present at a building or structure, it shall be permitted to bond only one into the grounding electrode system.

300.5

Underground service conductors shall be protected from damage in accordance with ____ including minimum coverage requirements.

12 AWG copper

Underground service conductors that supply power to limited loads of a single branch circuit shall not be smaller than __ ___ ______.

d. a or b

Ungrounded alternating-current systems from 50V to less than 1000V shall be legibly marked "Caution: Ungrounded System - Operating ______ Volts Between Conductors" at _________ of the system, with sufficient durability to withstand the environment involved. a. the source b. the first disconnecting means c. every junction box d. a or b

d. any of these

Where a building or structure contains more than one service disconnect in separate enclosures, grounding electrode connections shall be permitted to be ____. a. multiple individual grounding electrode conductors b. one grounding electrode conductor in a common location c. a common grounding electrode conductor and taps d. any of these

30 in

Where rock bottom is encountered when driving a ground rod at an angle up to 45 degrees, the electrode can be buried in a trench that is at least ____ deep.

d. a and b

____ shall not be used as grounding electrodes. a. metal underground gas piping systems b. aluminum c. metal well casings d. a and b

20

A bare 4 AWG copper conductor installed horizontally near the bottom or vertically, and within that portion of a concrete foundation or footing that is in direct contact with the earth, can be used as a grounding electrode when the conductor is at least __ ft. in length.

grounding electrode

A separate bonding jumper to the building structural metal shall not be required if the metal frame of a building or structure is used as the _________ _________ for the separately derived system.

1000A

Ground-fault protection of equipment shall be provided for solidly grounded wye electrical systems of more than 150 volts-to-ground, but not exceeding 1000V phase-to-phase for each individual device used a a building or structure main disconnecting means rated _____ or more, unless specifically exempted.

d. all of these

High-impedance grounded neutral systems shall be permitted for three-phase ac systems of 480V to 1000V where ____. a. the conditions of maintenance and supervision ensure that only qualified persons service the installation b. ground detectors are installed on the system c. line-to-neutral loads are not served d. all of these

d) any of these

The continuity of a grounded conductor shall not depend on a connection to ____. a. a metallic enclosure b. a raceway c. cable armor d. any of these

main bonding jumper

The grounded conductor of an alternating-current system operating at 1000V or less shall be routed with the ungrounded conductors and connected to each disconnecting means grounded conductor terminal or bus, which is then connected to the service disconnecting means enclosure via a ____ _______ ______ that is installed between the service neutral conductor and the serive disconnecting means enclosure.

True

True or False: Grounding electrode conductors that are not subject to physical damage can be run exposed along the surface of the building construction if securely fastened to the surface on which it is carried.

True

True or False: Single-pole breakers with identified handles ties can be used to protect each ungrounded conductor for line-to-line connected loads.

True

True or False: Surge arrestors 1000V or less are also known as Type 1 surge protective devices (SPDs).

True

True or False: A grounded circuit conductor is permitted to ground noncurrent carrying metal parts of the equipment, raceways, and other enclosures on the supply side or within the enclosure of the ac service disconnecting means.

wye-connected

A three-phase, 4-wire, ____________ power system used to supply power to nonlinear loads may necessitate that the power system design allow for the possibility of high harmonic currents on the neutral conductor.

True

True or False: Ferrous metal raceways and enclosures for grounding electrode conductors shall be electrically continuous from the point of attachment to cabinets or equipment to the grounding electrode.

True

True or False: Surge protective devices shall be marked with a short-circuit current rating and shall not be installed where the available fault current is in excess of that rating.

c. a and b

Ungrounded alternating-current systems from 50V to 1000V or less that are not required to be grounded in accordance with 250.20(b) shall have ____. a. ground detectors installed for ac systems operating at not less than 120V and at 1000V or less b. the ground detection sensing equipment connected as close as practicable to where the system receives its supply c. a and b d. ground fault protection for equipment

four

When sizing a feeder for the fixed appliance loads in dwelling units, a demand factor of 75 percent of the total nameplate ratings can be applied if there are ____ of more appliances fastened in place on the same feeder.

circular mil area

When ungrounded circuit conductors are increased in size to account for voltage drop, the wire-type equipment grounding conductor shall be proportionately increased in size according to the increase in size of the ungrounded conductors using their ________ ___ ____.

5

Where fixed multioutlet assemblies are used in other than dwelling unites or the guest rooms of hotels or motels, each ______ ft or fraction thereof of each separate and continuous length shall be considered as one outlet of no less than 180 VA where appliances are unlikely to be used simultaneously.

d. all of these

Overcurrent devices are not permitted to be located in the bathrooms of ____. a. dwelling units b. dormitories c. guest rooms or guest suites of hotels or motels d. all of these

largest of

Where it is unlikely that two or more noncoincident loads will be used simultaneously, only the _______ __ the loads used at one time is required to be used in computing the total load to a feeder.


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