Code

Dry-type transformers installed indoors and rated 112 1/2kVA shall have a separation of at least__ from combustible material unless separated from the combustible material be a fire-resistant, heat-insulated barrier.

1 foot. Article 450.21(A)

What is the minimum separation distance from combustible material for a 100kVA dry-type transformer installed indoors unless separated from the combustible material by a fire-resistant, heat resistant barrier?

1 foot. Article 450.21(A)

What is the MINIMUM fire-resistant construction rating of the room housing a 300kVA dry-type transformer installed indoors?

1 hour. Article 450.21(B)

Calculate dimension "A" in the drawing labeled Figure 4?

15 inches.. Article 314.28(A)(2) 6 x the largest raceway plus all others on the same wall(6x2"+2"+1"=15")

What is the maximum continuous load, in kW, that may be supplied by a 480V, 3 phase, 150 amp branch circuit?

155.7kW. Article 210.19(A) 480v x 150a x 1.73 x 1.25= 155,700w.

What is the MAXIMUM rating of the secondary circuits supplying circuits supplying an isolating power supply for low-voltage lighting systems operating at 30volts or less under any load conditions?

25 amps. Article 411.3

The walls and roofs of electrical vaults over 600 Volts shall be constructed of materials that have adequate structural strength for the conditions, with a minimum fire resistance of?

3 hours. Article 110.31(A)(1)

The NEC recommends that voltage drop be limited to __ percent on heating and appliance branch-circuits to provide reasonable efficiency of operation..

3%. Article 210.19(A)I.N no.4

What is the MINIMUM workspace required for 2 panels across from each other?

4 feet. Article 110.26(A)(1) cond. 3- live parts on both sides, 4 ft clearance

What is the minimum size metal junction box required for 4-10AWG conductors and 2-6AWG conductors?

4 x 2-1/8" square box. Table 314.16(A) &(B) 10AWG=2.5cu in, 6AWG=5 cu in (4x2.5)+(2x5)= 20 cu in

Threaded entries into explosionprrof equipment shall be made up with at least ____ threads fully engaged.

5. Article 500.8(E)(1)

In a completed seal, the minimum thickness of the sealing compound shall not be less than___ for an installation of 1/2" conduit.

5/8". Article 501.15(C)(3)

A fence shall not be less than 7ft in height or a combination of__ or more of fence fabric and 1ft or more extension utilizing three or more strands of barbed wire or equivalent.

6ft. Article 110.31

The maximum weight of a ceiling suspended paddle fan, in pounds, which a listed paddle fan outlet box is permitted to be used as the sole support for the fan is__ pounds..

70 pounds. Article 314.28(C)

What is the minimum width of working space in front of an electrical motor control center rated at 480V with no live or grounded parts in front of the panel. The panel measures 78 inches wide.

78 inches. Article 110.26(A)(2)

Equipment rated at___ or more that contain over current devices, switching devices, or control devices is installed and there is a personnel door(s) intended for entrance to and egress from the working space less than 25-feet from the nearest edge of the working space, the door(s) shall be open in the direction of egress and be equipped with listed panic hardware.

800 amps. Article 110.26(C)(3)

For the purpose of determining boxfill, use Figure 9, to calculate the number of conductors in the junction box?

9. Article 314.16... Fixture wires are counted because they leave the box

A 25-foot feeder tap conductor must terminate in _____?

A single set of fuses that will limit the load to the ampacity of the tap conductors; A single circuit breaker that will limit the load to the ampacity of the tap conductors.. Article 240.21(B)(2)(2)

Wiring systems inside boxes must be installed so that the conductors contained in them can ___ without removing any part of the building.

Be rendered accessible. Article 314.29

A load where the maximum current is expected to continue for 3 hours or more is a?

Continuous load. Article 100

Luminaries installed under a marquee shall be considered installed in a __ location.

Damp. Article 100

An electrical supply point from which service drops, service laterals, feeders, or branch circuits to agricultural buildings, associated farm dwellings, and associated buildings under single management is defined as:

Distribution point. Article 547.2

Class 2 locations are those that are hazardous because of the presence of___?

Dust. Article 502.1

What is the purpose of the NEC?

Practical safeguarding of persons and property from electrical hazards arising from the use of electricity. Article 90.1(A)

Electrical equipment rooms or enclosures housing electrical apparatus that are controlled be a lock(s) shall be considered accessible to?

Qualified persons. Article 110.26(F)

Which of the filling is NOT considered a Health Care Facility? Dentist office; Nursing Home; Hospital; Veterinarian Office

Veterinarian office. Article 517.2

As listed in Table 310.13, paper insulation shall be permitted to be used as insulation for underground service conductors, or by special permission. As used on this table, special permission means?

Written consent of the authority having jurisdiction. Article 100

The Maximum current that a conductor can carry continuously under the conditions of use without exceeding its temperature rating best defines?

ampacity. Article 100

Cartridge fuses and fuseholders shall be classified according to voltage and ampere ranges. Fuses rated__ Volts nominal, or less shall be permitted to be used for voltages at or below their ratings..

1,000 Volts. Article 240.61

In a damp or wet location, surface type enclosures shall be placed or equipped to prevent moisture or water from entering and accumulating within the cabinet or cutout box, and shall be mounted so there is at least__ airspace between the enclosure and the wall or supporting surface.

1/4". Article 312.2

In walls of concrete, tile, or other noncombustible material, cabinets, cutout boxes, or meter socket enclosures shall be installed so that the front edge of the cabinet is not set back of the finished surface more than___. In walls constructed of wood or other combustible material, cabinets shall be flush with the finished surface or project there.

1/4". Article 312.3

Doors and covers of enclosures used on systems rated over 600 Volts, used solely as pull boxes l, splice boxes, or junction boxes shall be locked, bolted, or screwed on. Underground box covers that weigh over__ shall be considered as meeting this requirement.

100 pounds. Article 110.31(D)

Three conductors pass unbroken through a box. In addition, one hot conductor is spliced to a conductor going to a switch(switch leg). A neutral is spliced to a fixture wire and carries on through the box. A switch leg is spliced to a fixture wire. The two fixture wires supply a lighting fixture. There is a fixture stud and a fixture hickey installed in the box. All conductors are No. 12 in metal raceways with metal boxes. There are no cable clamps contained within the box. Calculate the number of the conductors in the box for the purposes of determining box fill?

12. Article 314.16(B)

Calculate dimension "A" in the drawing labeled Figure 8?

16 inches. Article 314.28(A)(2) 6x the largest raceway plus all others on the same wall.. (6x2.5"+1"=16")

A single-phase, 120/240V, 200 ampere feeder is protected a 200-ampere breaker not listed for continuous operation at 100% of its rating. It already supplies an 80-ampere, 240V continuous lighting load. What is the maximum permitted amount of continuous load which may be added to the feeder?(answer in watts)

19,200watts. (200x.8=160amps-80amps(existing load)= 80amps x 240V= 19,200w.. Article 215.3

What is the ampacity of an aluminum copper busbar measuring 5" wide and 5/8" thick contained in sheet metallic auxiliary gutter?

2,188amps. Article 366.23 (5" x 5/8" x700=2,188)

What is the ampacity of a copper busbar measuring 3" wide and 3/4" thick contained in sheet metallic auxiliary gutter?

2,250amps. Article 366.23 (3" x 3/4" x 1,000=2250amp)

The minimum number of outdoor receptacle outlets required for a single-family dwelling is __ receptacles, one located on the front of the dwelling and one located on the back of the dwelling.

2. Article 210.52(E)(1)

A door sill or curb of a transformer vault shall be of sufficient height to confine the oil from the largest transformer within the vault shall be provided, and in no-case shall the height be less than?

4 inches. Article 450.43(B)

A conduit nipple between a panel board and a wire way is 36" long and contains 4-3/0 THHN conductors and 1-#2 AWG wire. The maximum total cross-sectional area conductor fill capacity for this raceway is?

40%. Table 1, chapter 9

What is the ampacity of a 600-McMillan THHN copper conductor, when used with equipment rated 75 degrees Celcius?

420 amps. Table 310.15(B)(16), use 75degree column because of temp. Of terminations.. 110.14(C)

What is the minimum required headroom of the working space of a switchgear that measures 96 inches high?

96 inches. Article 110.26(A)(3)

Which of the following would qualify for guarding live parts measured at 12,470 Volts?

A 6 foot chain link fence with 12 inches of barbed wire.

Unused cable or raceway openings in boxes, cabinets, and cutout boxes shall be__ to afford protection substantially equivalent to the wall of the equipment..

Effectively closed. Article 110.12(A)

All circuit conductors between the service equipment, the source of a separately derived system, or other power supply source and the final branch-circuit overcurrent device are considered as___ conductors.

Feeder. Article 100

Openings around electrical penetrations through fire resistance rated walls, partitions, floors or ceilings shall be___using approved methods to maintain the fire resistance rating..

Fire stopped. Article 300.21

The voltage rating of equipment shall not be__ the nominal voltage of a circuit to which it is connected.

Less than. Article 110.4

___ equipment shall be installed and used in accordance with any instructions included in the listing or labeling..

Listed or labeled. Article 110.3(B)

Which of the following is NOT a device? dwelling unit system doorbell pushbutton; security alarm system door contact; fire alarm manual pull station; loud speaker

Loud speaker. Article 100

All conductors installed in manhole installations shall be cabled__, or arranged in an approved manner that provides ready and safe access for persons to enter for installation and maintenance..

Racked up. Article 110.74

The transit authority is installing a washing station for buses at the bus garage. All exposed boxes, fittings, conduits, and cable inside the wash station shall be installed___..

So there is a 1/4" airspace between it and the wall. Article 300.60(D)

Which of the following describes the meaning of "ampacity of a conductor"?

The current a conductor can carry continuosly under the conditions of use without exceeding its temperature rating

Which of the following is true when using the American Wire Gauge(AWG)?

The smaller the number the larger the wire. Table 8, chapter 9