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Flashcards in PEC 4 Deck (101):
1

Where installed in raceways conductors of size ____(mm2) and larger shall be stranded

8.0 mm2

2

A ________conductor has a trade name “moisture resistant thermoplastic”.

Type THHN

3

When the voltage between conductors does NOT exceed _____V and the roof has a slope of NOT less than _____(mm) in ______,(mm) the clearance can be reduced to _______(mm).

300 V
100 mm, 300 mm
1,000 mm

4

The down conductors shall be protected for a minimum distance of _______(mm) above grade level.

1,800 mm

5

Fuses shall be plainly marked with: (3)

ampere rating, voltage rating, and interrupting rating.

6

Which of the following statements is NOT true about grounding electrode conductor?

It shall be solid or stranded
It must be continuous
Splice or joints are allowed
It shall be insulated, covered or bare

Splice or joints are allowed

7

The uses of non-metallic extensions are NOT allowed in all but one of the following. Which one is this?

As an aerial cable
Where exposed to corrosive vapors
Where subject to corrosive vapors
Through floors or partitions

Where subject to corrosive vapors

8

Fixture wires shall NOT be used as ___________________

branch circuit conductors.

9

Exposed energized parts of motors and controllers shall be guarded against ________ by elevating it __________(mm) or more above the floor.

accidental contact
2,400 mm

10

Exposed energized parts of motor and controller operating at ___V or more between terminals shall be guarded against accidental contact by enclosure.

50 V

11

To improve the insulation resistance of a motor, it is first cleaned, washed, varnished then baked. Which is very economical and effective method of baking particularly the inside coils of a large motor?

Putting incandescent lamps around the winding and cover
Hanging resistor strips inside the core and cover
Putting it inside the baking oven and control the oven temperature
Connecting the terminals to variable low voltage supply and increase the baking current gradually until the desired baking temperature is attained, making sure that the rated current is not exceed.

Putting it inside the baking oven and control the oven temperature

12

_________ includes any switch or device normally used to start and stop a motor by making and breaking the motor circuit current.

Controller

13

Grounding electrodes shall be installed such that at least _______(mm) of length is in contact with the soil.

2,400 mm

14

Lamps installed in scene docks shall be so located and guarded and shall provide an air space of NOT less than _______ (mm)between such lamps and any combustible material.

50 mm

15

Direct burial cables or conductors with a nominal voltage of ____V or less and placed under a one or two family dwelling driveways and parking areas shall have a minimum cover distance of______(mm).

660 V
460 mm

16

A _________ conductor has a trade name “heat-resistant rubber”.

Type RH

17

is the permanent joining of metallic parts to form an electrically conductive path which will assure electrical continuity and the capacity to conduct safely any current likely to be imposed. (April 2016)

Bonding

18

A metal ungrounded gas piping system _______ as a grounding system.

shall not be used

19

Cartridge fused and fuse holders shall have a maximum operating voltage of ______V.

300 V

20

The Building Code (PD 1096) of the Philippines has several referral codes. The only no-referral code is

The Philippine Electrical Code
Fire Code
Structural Code
Chemical Engineering Code

Chemical Engineering Code

21

________ conductors are used for machine tool wiring in dry or wet locations.

Type MTW

22

Fuses, circuit breakers or combinations thereof shall NOT be connected in ______.

parallel

23

At least _____(mm) of free conductor shall be left at each outlet, junction and switch point for splices or the connection of fixtures or devices.

150 mm

24

. Which of the following cables is NOT used as an electrical cable?

Flat cables
Optical fiber cables
Armored cables
Steel cables

Steel cables

25

Electrodes of pipe or conduit shall NOT be smaller than ______(mm) trade size.

20 mm

26

_______(mm2) TW copper has an ampacity equal to _______(A)

8.0 mm2
40 A

27

The derating factors for the number of wires in a raceway shall not apply to conductors in nipples having a length NOT exceeding _____(mm).

600 mm

28

is an enclosure either above or below ground, with fire resistant walls, ceiling and floor exclusively built for unattended transformer and their auxiliaries.

Transformer vault

29

A certain residential house lighting load of 1.1 kVA and an appliance load of 10 A at 220 V, single phase, two wires, 60 Hz. The branch circuit fuse protections for lighting and appliance loads are _____(2) respectively.

15 A & 20 A

30

One of the approved grounding electrode system is using the metal underground water pipe in direct contact with the earth for _________(mm) or more.

3,000 mm

31

is the minimum temperature at which a given liquid gives off vapor in sufficient concentration to form an ignitable mixture.

Flash point

32

One equipment shall in sight from another equipment NOT more than _____m from the other.

15 m

33

Lamp holders installed over highly combustible material shall be located at least ______(mm) above the floor

2,400 mm

34

How can the polarization index of transformer oil be improved?

Ans. Filtering

35

Ground terminals shall be: (3)

solid plate, stranded cable, and solid wire or rod.

36

Which of the following statements is NOT true regarding a rosette?

Fusible rosette shall NOT be installed
Rosettes installed in damp or wet locations shall be or weatherproof type
Separable rosettes that may change polarity shall NOT be used
None of these

None of these

37

Sheet metal of flush and recessed fixture housings shall be protected against corrosion and shall NOT be less than _______(mm) thick.

0.65 mm

38

What is the size in square millimeters (mm2) of the cable 250 MCM in size?

Ans. 125 mm2

39

Metal fixtures, transformers and transformer enclosures on circuits operating at over _____V to ground shall be grounded.

150 V

40

NOT less than ____(mm) of free non-heating lead shall be within the junction box.

150 mm

41

A circle with the letter B stands for outlet with _______.

blank cover

42

The ampacity of branch circuit conductors and the rating or setting of over-current devices supplying fixed electric space heating equipment for pipelines and vessels shall be NOT less than ____% of the total load of the heaters.

125%

43

Motors with a marked temperature rise NOT over ___C shall have an overload protection equal to ____% of the motor full load current.

40C
115%

44

For __________________________________ the number of overload units required shall be __, in either ___________

single-phase AC or DC motors supplied by a 3-wire, single-phase AC or DC with grounded neutral,

1

ungrounded conductor.

45

For wound rotors, to determine the maximum setting of its short circuit protective device, using a fuse or an inverse time circuit breaker, a multiplying factor of ____ of its current rating shall be used.

150%

46

The construction of metal cabinets and cutout boxes shall be such as to secure strength and rigidity. If constructed of_____________ the metal thickness should NOT be less than _____(mm).

uncoated sheet steel,
1.35 mm

47

The floors of transformer vaults in contact with the earth shall be of ______ NOT less than _____ (mm) thick.

concrete
100 mm

48

The nominal battery voltage shall be computed on the basis of _____V per cell for the lead acid type.

2.0 V

49

___________ – Hazardous locations, in which volatile flammable gases are handled, processed or used.

Class I, Division 2

50

In mobile homes, if a range, clothes dryer or similar appliance is connected by metal covered cable or flexible metal conduit, a length of NOT less than _______(mm) of free cable or conduit shall be provided to permit moving the appliance.

900 mm

51

Conductors passing from windows, doors, porches, fire escapes or similar locations shall
maintain a horizontal clearance of ________(mm).

1,000 mm

52

is the horizontal distance between two adjacent supporting points of a conductor.

Span

53

is the temperature rating of a TW insulated conductor.

60C

54

__________are the supply conductors that extend from the street main or from
transformer to the service equipment of the premises supplied.

Service conductors

55

Concealed knob and tube wiring shall be supported at intervals NOT exceeding ________(mm).

1,300 mm

56

A dead end of a busway shall be _______.

closed

57

What is the diameter of a solid wire, which is equivalent to 5.5 mm2?

Ans. d = 2.65 mm


58

_____ is a factory assembly of one or more conductors insulated with a highly
compressed refractory mineral insulation and enclosed in a liquid tight and gas tight
continuous copper or alloy steel sheath.

Type MI

59

The combined cross-sectional area of all conductors or cables shall NOT exceed ___% of the
internal cross-sectional area of the raceway.

40%

60

No conductors larger than _____(mm2) shal l be installed in _________ raceways.

50 mm2
cellular metal floor

61

In mobile homes, ___________ shall NOT be installed within ______ (mm) of shower or
bathtub space.

receptacle outlets
760 mm

62

Rigid non-metallic conduit shall be supported within ________(mm) of each box, cabinet or other
conduit termination.

900 mm

63

Every recreational vehicle site with electrical supply shall be equipped with at least __ ,

1
20A, 250 V receptacle.

64

A main disconnecting means shall be provided where fuses are used or where more than _
circuit breakers are employed.

2

65

For (3) recreational vehicle sites, the demand factor for feeder and service entrance
conductors shall be ____%.

100%

66

Conductors in open wiring on insulators shall be rigidly supported within ______(mm) of a
dead end connection to a rosette, lamp holder or receptacle.

300 mm

67

Electrical metallic tubing smaller than ____(mm) electrical trade size shall NOT be used.

15 mm

68

(mm) is the maximum distance between open service conductor supports for a
voltage of up to 300 V.

1,300 mm

69

Concealed knob and tube wiring shall be permitted to be used (3)

For extensions of existing installations
In unfinished attic and roof spaces
In the hollow spaces of walls and ceilings

.

70

Type AC cable shall be secured by approved staples, straps hangers o r similar fittings at
interval NOT exceeding _______(mm)`.

1,300 mm

71

Where coaxial cable is attached to building, they should have a separation of at least _____(mm) from electric light or power cables.

100mm

72

Type MC cable shall be permitted for systems in excess of ____V

600 V.

73

For smooth sheath cables (type MC) with an external diameter of more than _____(mm), shall have a bending radius of NOT less than ______ the metallic sheath of the cable.

38 mm
15 times

74

Cables that are flame retardant and have limited smoke characteristics shall be permitted to be identified with the suffix ___.

LS

75

Flat cable assembly shall be installed for ________ only.

exposed work

76

is the minimum clearance of service drops over sidewalks.

10 ft

77

The overall covering of type NM (non-metallic sheathed) cable shall be (2).

flame retardant and moisture resistant

78

______ is an assembly of two pieces of insulating material provided with grooves for holding one or more conductors at a definite spacing from the surface wired over and from each other, and with holes for fastening in position.

Cleat

79

Type TC (power and control tray) cable shall be permitted to be used in any of the following EXCEPT one. Which one is this?

In raceway
In cable trays in hazardous (classified) locations
For power, lighting, control, signal and communication circuits
Where exposed to direct rays of the sun

Where exposed to direct rays of the sun

80

A phase converter is usually employed to convert single-phase to three-phase power supply so that three-phase motors maybe used. For this service, the ___ specifies that the single-phase conductors shall have an ampacity of NOT less than ____% of the full load current rating of motor or load being served where the input and the output voltages are identical.

PEC
216%

81

The smallest electrical trade size for rigid non-metallic conduit is ____(mm).

20 mm

82

Where flexible metal conduit is installed as a fixed raceway, it shall be secured within _____(mm) on each side of every outlet box.

300 mm

83

The signatures that are needed in the application form for an electrical permit: (3)


Owner or authorized representative
PEE who signed and sealed the electrical plan
Electrical practitioner in-charge of the installation

84

In the installation of power resistors, a thermal barrier shall be required if the space between the resistors and any combustible material is less than _____(mm).

300 mm

85

Splices and taps shall be made only in __________

junction boxes.

86

The size of conductors in ________ shall be in no case smaller than_____(mm2).

cable bus system
50 mm2

87

Electrical non-metallic tubing shall be firmly fastened within _______(mm) of each outlet box, junction box, cabinet or fittings.

900 mm

88

In estimating the loading of a branch circuit, the loading shall be used for each receptacle is ____(VA).

180 VA

89

Nails where used as a fastening means, shall be permitted to pass through the interior of the enclosure if located within ______(mm) of the back or ends of the enclosure.

6.4 mm

90

The conductors including splices and taps shall NOT fill the auxiliary gutter to more than ____% of its area

75%

91

A space of _______(mm) or more shall be provided between the top of any switchboard and any combustible ceiling.

1,000 mm

92

______(ohms) is the minimum insulation resistance of a building’s electrical wiring for circuits using ______(mm2) or ________(mm2) conductors.

500,000 ohms
2.0 mm2
3.5 mm2

93

NOT more than __ over-current devices of a lighting and appliance branch circuit panelboard shall be installed in any cabinet or cutout box.

48

94

For non-insulated busbars, the minimum spacing between it and the bottom of the enclosure shall be _____(mm).

255 mm

95

is a form of air switch in which the moving element is a hinged blade wedge between stationary contact blades when closed.

Knife

96

Open conductors passing over residential driveways and those commercial areas NOT subject to truck traffic where the voltage is limited to _____V to ground shall maintain a vertical distance of _______(mm).

300 V
3,700 mm

97

In wiring using rigid metal conduits, conduit smaller than _______(mm) shall NOT be used.

15 mm

98

is the operation for alternate intervals.

Intermittent duty

99

Festoon lighting is a string of outdoor lights suspended between two points more than ________(mm) apart.

4,500 mm

100

From signs, chimneys, radio and television antennas or similar, clearances through vertical, diagonal and horizontal shall NOT be less than _________(mm).

1,000 mm

101

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