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