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Flashcards in PEC 7 Deck (101):
1

A wall screen or fence less than_______(mm) in height shall NOT be considered as a preventing access unless it has other features that provide a degree of isolation equivalent to the height of the fence in question.

2,500 mm

2

Branch circuit conductors supplying a single-phase motor shall have an ampacity NOT exceeding ____%

125%.

3

Pits within _____(mm) horizontally from the flammable vapor source, shall be considered a hazardous location under Class I, Division 1 location.

7,600 mm

4

Type TW conductor is a ___________(2). (April 2016)

moisture resistant and thermoplastic type

5

is the current in amperes a conductor can carry continuously under the conditions of use without exceeding its temperature rating.

Ampacity

6

. Flat conductor cables maybe installed in any of the following location EXCEPT one. Which one is this?

On hard concrete flooring
In wet locations
For branch circuits
In damp locations

In wet locations

7

is an operation of loads and for intervals of time, both of which may be subject to wide variations.

Varying duty

8

For equipment rated _____A and over, ____(mm) wide containing over-current devices and control devices at least one entrance of NOT less than _____(mm) wide and ____(mm) high shall be provided at each end.

1,200 A
1,900 mm

600 mm
2,000 mm

9

Batteries and direct current circuits shall be physically separated by at least a ____(mm) gap or other approved means from circuits of a different power source.

12 mm

10

Where contactors are used as the disconnecting means for fuses, an individually externally operable switch, such as tumbler switch for the control of each contactor shall be located at a distance of NOT more than _____(mm) from the contactor.

1,800 mm

11

No electrical installation, alteration and or addition shall be connected or reconnected to any power supply or any other sources of electrical energy without ________

certificate of final inspection.

12

4) 3-phase motor are supplied by one common feeder cable. The full load current ratings of the motors are 10 A, 20 A, 30 A and 40 A. What should be the minimum ampacity of the feeder cable?

Ans. 110 A

Feeder ampacity = Sum of FLAs + 25% of largest FLA Feeder ampacity = 10 + 20 + 30 + 40 + 0.25(40) = 110 A

13

Thermal barrier shall be required if the space between the resistors and reactors and any combustible material is less than_____

300 mm.

14

The ampacity of conductors that connect a capacitor to the terminals of a motor circuit conductor shall NOT be less than ____ the ampacity of the motor circuit conductors and in no case less than 135% of the rated capacitor current.

1/3

15

. The load for each ________ feeder and service conductor supplying 5 to 8 receptacles that supply shore power for boats shall be calculated as___% of the sum of the rating of the receptacles.

ungrounded
90%

16

is a device actuated by the operation of some devices with which it is directly associated, to govern succeeding operations of some or allied devices.

Interlock

17

is the service conductors between the street main, including any risers at pole or other structure or from transformers and the first point of connection to the service entrance conductors.

Service lateral

18

For 101 A to 200 A circuits, the minimum insulation required shall be______Ohms.

50,000 ohms

19

____ is NOT a standard kVA rating of a single-phase transformer.

175 kVA

20

For voltages above 600 V, the minimum insulation resistance shall be ________ ohms per kilovolt rating.

1,000,000 ohms

21

The rating of any cord and plug connected utilization equipment shall NOT exceed __% of the branch circuit rating.

80%

22

If there will six or more 2-wire branch circuits, the service disconnecting means shall NOT be smaller than ______.

100 A

23

For direct current motors, the multiplying factor to be used in selecting the size of over-current device using an inverse time CB shall be ____% of its full load current.

150%

24

Specifications written on the plans or submitted on separate standard size sheets shall show…

(3)

Types of wiring, i.e. service entrance, branch circuits, feeders, etc
Nature of electrical service, i.e. no. of phase, voltage, frequency, etc
Special equipment to be installed indicating ratings

25

is an appliance which is fixed in one place to another in normal use.

Stationary appliance

26

In starting a large DC motor, a starter is primarily used in order to _____ the starting current.

limit

27

__________ – Hazardous locations in which easily ignitable fibers are stored and handled.

Class III, Division 2

28

In commercial garages, repair and storage areas, the entire area up to a level of _____(mm) above the floor shall be considered to be Class I, Division 2 hazardous location

460 mm

29

Conductors passing over roof surface, a vertical clearance of _____(mm) shall be maintained.

2,500 mm

30

In this new Electrical Engineering Law, what is the official designation of “master electrician”?

Ans. Registered Master Electrician

31

is the maximum load consumed or produced by a unit or group of units in a stated period of time.

Peak load

32

is a transformer of the multiple winding type with the primary and secondary winding physically separated which inductively couples its secondary winding to the grounded feeder system that energize its primary winding.

Isolation transformer

33

In judging the suitability of electrical equipment for proper mounting, the following factors should be considered, one of which is the LEAST important. Which one is this?

Type of enclosure
Wire bending space
Electrical insulation
Mechanical strength

Electrical insulation

34

The branches of the emergency system in a hospital shall be installed and connected to the alternate power source so that all functions shall automatically restored to operation within _____ after interruption of the normal source.

10 seconds

35

_________(mm) is the minimum distance of open conductors of not over 600 V and above finished grade, sidewalks or form any flat form or projection which they might be reached where the supply conductors are limited to 150 V to ground and accessible to pedestrians only.

3,100 mm

36

Which of the following wiring cables is most suitable for shipboard installations?

Flat cable assembly
Shielded non-metallic sheathed cable
Metal clad cable
Armored cable

Armored cable

37

If there will be four or more appliances fastened in place and served by the same feeder, it shall be permissible to apply a demand factor of____% to the total nameplate ratings of the loads.

75%

38

All exposed incandescent lamps in dressing rooms, where less than______(mm) from the floor, shall be equipped with open end guards riveted to the outlet or otherwise locked in place.

2,400 mm

39

___% is the maximum allowable voltage drop from the main circuit breaker to the farthest lamp load.

5%

40

Where the voltage between conductors does NOT exceed ____V and the roof has a slope of NOT less than ____(mm) in ____(mm), a reduction to _____(mm) of the distance of the service conductors from the roof surface shall be permitted.

300 V
100 mm, 300 mm
1,000 mm

41

If there are no over-current protective device rated 30 A or less with neutral connection, this panelboard is classified as a _______.

power panelboard

42

_________ is a branch circuit that supplies only one utilization equipment

Individual branch circuit

43

In halls, corridors, closets and stairways of any occupancy EXCEPT one family dwelling unit, a general lighting load of _____VA/m2 shall be considered.

4 VA/m2

44

At least one receptacle outlet shall be installed directly above a show window for each ____ linear meter length or a major fraction thereof.

three

45

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

Service point

46

According to the Code the minimum insulation level for neutral conductor of residential installation which has solidly grounded system shall be ____V

300 V

47

A demand factor of ____% of maximum possible connected load for television studio sets shall be permitted for all portable feeders.

50%

48

For office buildings, a general lighting load of ____VA/m2 shall be used.

28 VA/m2

49

An insulated conductor intended for use as a________where contained within a flexible cord shall be identified by a _________ outlet finish color.

grounded conductor
white or a natural gray

50

The allowable ampacities of conductors rated from 0 to 2,000 volts, 60C to 90C and not more than three of them in raceway, cable or earth is based on an ambient temperature of ___C.

30C

51

Busways shal l be permi tted to be instal led behind panels i f means of access are p rovided
and i f the conditions below are met. One of them is NOT val id. Which one is this?

No over-current devices are instal led on the busway other than for an individual fixture
The busway is so instal led that the joints between sections and fi tting are a ccessible
for maintenance purposes
The busway is open and of the ventilator type
The space behind the panels is not for air handling purposes

The busway is open and of the ventilator type

52

The OCPD for resistance welders shall NOT exceed ___% of the con du ct o r ’s ampacity
supplying the circuit.

300%

53

For instal lations to supply only l imi ted load of a single branch circui t, the service
disconnecting means shall have a rating of NOT less than ___(A).

15 A

54

_______ can be used in systems of 600 V or more.

Metal clad cable (MC)

55

Open conductors passing over residential driveways and those commercial areas not
subject to truck traffic where the vol tage exceeds 300 V to ground shal l have a vertical
clearance of _____(mm).

4,600 mm

56

MC cable insulation shall have a maximum operating temperature of NOT less than __ C

90C.

57

The ampacity of conductors in non-metal l ic sheathed cable shall be used at . ___C

60C

58

. What is the radius of a sol id round conductor, which is the nearest equivalent of a
stranded conductor whose total area is exactly 8 mm2?

Ans. 3.191 mm

59

For high impedance grounding, the system _____ conductor shall NOT be connected to
the ground EXCEPT through the ________

neutral

grounding impedance

60

Service equipment rated over 600 V located on mezzanine floors shal l be required to be
accessible by permanent _______.

stairways & ladders

61

The load for household electric clothes dryer in a dwelling unit is the larger of the
nameplate rating or ______VA

5,000 VA

62

Each l ighting and appl iance branch circui t panelboard shal l be protected individual ly on the
supply side by NOT more than two main CBs or two sets of fuses having a combined rati ng
NOT _______ than that of the panelboard.

greater

63

The long time rating for x-ray equipment is based on an operating time of ______ or
longer.

5 minutes

64

For circuits supplying loads consisting of motor operated utilization equipment that is
fastened in place and that has a motor larger than ___ in combination with other
loads, the total computed load shall be base on ____% of the largest motor load plus the
sum of the other loads.

0.125 hp

125%

65

Exposed AC cable shall closely follow the ___ of the building.

finish

66

A 3-phase general purpose squirrel cage motor draws a full load current of 40 A. what is
the maximum size of time delay that may be used for short circuit protection?

Ans. 80 A

Size = 175% of FLA = 1.75(40) = 70 A
The closest higher standard rating is an 80 A fuse.

67

A 5.5 mm2 TW copper conductor has a conductor ampacity of ___A.

30 A

68

The branch circuit load for continuous duty receptacles shall be calculated at ____VA per receptacle.

180 VA

69

Ground rod clamps shall be secured with at least ____ or cap screws.

2 bolts

70

Over-current protection devices in emergency system shall… (3)



Be coordinated
Clear in steps
NOT trip the main device

71

________ is the underground service conductors between the street main, including any risers at the pole or other structure or from transformer and the first point of connection to the service entrance conductors in a terminal box. The point of connection is considered to be the point of entrance of the service conductors into the building.

Service lateral

72

________ on a heavy duty smoke or vent stacks shall be protected from physical damage or displacement for a distance of NOT less than _____(mm) above finish grade.

Down conductors
2,400 mm

73

The PEC permits (4) ___ bends in a single conduit run

90d

74

A warning sign shall be posted where _____ is available in service equipment.

high voltage

75

Circuits with a nominal voltage of 600 V or less in rigid metal or non-metallic conduit and placed under a minimum of 100 mm thick concrete exterior slab with no vehicular traffic shall have a minimum cover distance of _____(mm).

100 mm

76

Conductors supplying a group of motor-generator arc welders are sized at ____% of the third largest welder plus the percentage of the other welders.

85%

77

Which of the following statements on wiring in commercial garages and shops is NOT correct?

The ground conductor shall be connected to the ground terminal of the utilization equipment
Receptacles, attachment plugs and similar devices shall be of the polarized type
Lamps and lamp holders for fixed lighting that are located above vehicles shall be installed NOT lower than 2,500 mm
Battery chargers and batteries being charged shall NOT be located in location classified as hazardous

Lamps and lamp holders for fixed lighting that are located above vehicles shall be installed NOT lower than 2,500 mm

78

Conductors may travel horizontally through ________ of switchboards if isolated from busbars by a barrier.

vertical sections

79

There shall be no more than ________ per service grouped in any location.

6 disconnects

80

When a circuit breaker handles are operated vertically rather than horizontally, the “up” position of the handle shall be the __ position. (April 2016)

ON

81

AC equipment on board watercraft shall operate satisfactorily at _________ voltage limitations.

minus 5% to plus 10%

82

Emergency power panel conductors supplying a building are tapped on the ___________

line side of the service.

83

Where buildings exceed three stories or 15 meters in height, overhead lines shall be arranged, where practicable, so that a clear space of at least _______(mm) wide will be left to facilitate title raising of ladders when necessary for fire fighting.

1,900 mm

84

. For the purpose of lightning protection, a smoke or vent stack is classified as heavy duty if the cross sectional area of the flue is greater than ______m2 and the height is greater than 23 m.

0.32 m2

85

Voltage drop shall be considered to service laterals run at ____ distance.

long

86

Conductors used in lightning protection system shall have no bend forming an included angle of less than -___.

90d

87

Control conductors used for load management can be routed with the service entrance conductors in the same _________

raceway or cable

88

A lighting fixture shall be wired with a flexible lighting cord with a cross sectional area of NOT less than_____m2 of minimum area.

0.75 mm2

89

Service conductors shall NOT be run in such a manner as to block ________ to buildings.

openings

90

Continuous duty loads shall be figured at ____% for branch circuits

125%

91

Enclosures for over-current devices in damp or wet locations shall be identified for use in such locations and shall be mounted so there is at least _____(mm) air space between the enclosure and the wall.

10 mm

92

______conductor has a trade name “moisture and heat resistant rubber”.

Type RHW

93

is a grounding conductor installed over lighting cables for the purpose of interconnecting the system ground electrodes and providing lightning protection for the cables.

Counterpoise

94

The surge arrester for services less than 1,000 V connected by copper conductor to grounding electrode conductor or the equivalent grounding terminal shall NOT be smaller than ____.(mm2)

2 mm2

95

The OCPD for arc welders with transformers shall NOT exceed ____% of the primary full load current.

200%

96

On circuits of less than 1,000 V, the rating of the surge arrester shall be _________ the maximum continuous phase to ground power frequency voltage available at the point of application.

equal to or greater than

97

The long time rating used to select OCPDs to protect circuits to x-ray equipment shall be ____%.

100%

98

A 3.5 mm2 TW copper conductor has an ampacity equal to ____A.

20 A

99

Which of the following statement on lighting fixtures is NOT correct?

Outdoor lighting fixture and associated equipment shall be permitted to be supported by trees.
Metal fixtures and enclosures rated at 250 V and installed up in the ceiling shall be grounded
Stranded conductors shall be used in wiring a fixture supporting chain and other movable flexible parts
Fixtures and lighting equipment operating at over 250 V shall be grounded

Fixtures and lighting equipment operating at over 250 V shall be grounded

100

Conductors from the service point to the service disconnecting means are considered _____

service conductors.

101

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