PEC 7 Flashcards
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
Branch circuit conductors supplying a single-phase motor shall have an ampacity NOT exceeding ____%
125%.
Pits within _____(mm) horizontally from the flammable vapor source, shall be considered a hazardous location under Class I, Division 1 location.
7,600 mm
Type TW conductor is a ___________(2). (April 2016)
moisture resistant and thermoplastic type
is the current in amperes a conductor can carry continuously under the conditions of use without exceeding its temperature rating.
Ampacity
. 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
is an operation of loads and for intervals of time, both of which may be subject to wide variations.
Varying duty
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
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
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
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.
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
Thermal barrier shall be required if the space between the resistors and reactors and any combustible material is less than_____
300 mm.
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
. 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%
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
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
For 101 A to 200 A circuits, the minimum insulation required shall be______Ohms.
50,000 ohms
____ is NOT a standard kVA rating of a single-phase transformer.
175 kVA
For voltages above 600 V, the minimum insulation resistance shall be ________ ohms per kilovolt rating.
1,000,000 ohms
The rating of any cord and plug connected utilization equipment shall NOT exceed __% of the branch circuit rating.
80%
If there will six or more 2-wire branch circuits, the service disconnecting means shall NOT be smaller than ______.
100 A
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%
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
is an appliance which is fixed in one place to another in normal use.
Stationary appliance
In starting a large DC motor, a starter is primarily used in order to _____ the starting current.
limit
__________ – Hazardous locations in which easily ignitable fibers are stored and handled.
Class III, Division 2
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
Conductors passing over roof surface, a vertical clearance of _____(mm) shall be maintained.
2,500 mm
In this new Electrical Engineering Law, what is the official designation of “master electrician”?
Ans. Registered Master Electrician
is the maximum load consumed or produced by a unit or group of units in a stated period of time.
Peak load
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
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
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
_________(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
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
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%
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
___% is the maximum allowable voltage drop from the main circuit breaker to the farthest lamp load.
5%
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
If there are no over-current protective device rated 30 A or less with neutral connection, this panelboard is classified as a _______.
power panelboard
_________ is a branch circuit that supplies only one utilization equipment
Individual branch circuit
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
At least one receptacle outlet shall be installed directly above a show window for each ____ linear meter length or a major fraction thereof.
three
is the point of connection between the facilities of the serving utility and the premises wiring.
Service point
According to the Code the minimum insulation level for neutral conductor of residential installation which has solidly grounded system shall be ____V
300 V
A demand factor of ____% of maximum possible connected load for television studio sets shall be permitted for all portable feeders.
50%
For office buildings, a general lighting load of ____VA/m2 shall be used.
28 VA/m2
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
The allowable ampacities of conductors rated from 0 to 2,000 volts, 60C to 90C and not more than three of them in raceway, cable or earth is based on an ambient temperature of ___C.
30C
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
The OCPD for resistance welders shall NOT exceed ___% of the con du ct o r ’s ampacity
supplying the circuit.
300%
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
_______ can be used in systems of 600 V or more.
Metal clad cable (MC)
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
MC cable insulation shall have a maximum operating temperature of NOT less than __ C
90C.
The ampacity of conductors in non-metal l ic sheathed cable shall be used at . ___C
60C
. 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
For high impedance grounding, the system _____ conductor shall NOT be connected to
the ground EXCEPT through the ________
neutral
grounding impedance
Service equipment rated over 600 V located on mezzanine floors shal l be required to be
accessible by permanent _______.
stairways & ladders
The load for household electric clothes dryer in a dwelling unit is the larger of the
nameplate rating or ______VA
5,000 VA
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
The long time rating for x-ray equipment is based on an operating time of ______ or
longer.
5 minutes
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%
Exposed AC cable shall closely follow the ___ of the building.
finish
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.
A 5.5 mm2 TW copper conductor has a conductor ampacity of ___A.
30 A
The branch circuit load for continuous duty receptacles shall be calculated at ____VA per receptacle.
180 VA
Ground rod clamps shall be secured with at least ____ or cap screws.
2 bolts
Over-current protection devices in emergency system shall… (3)
Be coordinated
Clear in steps
NOT trip the main device
________ 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
________ 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
The PEC permits (4) ___ bends in a single conduit run
90d
A warning sign shall be posted where _____ is available in service equipment.
high voltage
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
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%
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
Conductors may travel horizontally through ________ of switchboards if isolated from busbars by a barrier.
vertical sections
There shall be no more than ________ per service grouped in any location.
6 disconnects
When a circuit breaker handles are operated vertically rather than horizontally, the “up” position of the handle shall be the __ position. (April 2016)
ON
AC equipment on board watercraft shall operate satisfactorily at _________ voltage limitations.
minus 5% to plus 10%
Emergency power panel conductors supplying a building are tapped on the ___________
line side of the service.
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
. 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
Voltage drop shall be considered to service laterals run at ____ distance.
long
Conductors used in lightning protection system shall have no bend forming an included angle of less than -___.
90d
Control conductors used for load management can be routed with the service entrance conductors in the same _________
raceway or cable
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
Service conductors shall NOT be run in such a manner as to block ________ to buildings.
openings
Continuous duty loads shall be figured at ____% for branch circuits
125%
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
______conductor has a trade name “moisture and heat resistant rubber”.
Type RHW
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
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
The OCPD for arc welders with transformers shall NOT exceed ____% of the primary full load current.
200%
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
The long time rating used to select OCPDs to protect circuits to x-ray equipment shall be ____%.
100%
A 3.5 mm2 TW copper conductor has an ampacity equal to ____A.
20 A
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
Conductors from the service point to the service disconnecting means are considered _____
service conductors.
.
.
