2. Philippine Electronics Code - Volume 1

GENERAL ENGINEERING AND APPLIED SCIENCES

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GENERAL ELECTRICAL PROTECTION AND GROUNDING REQUIREMENTS

Electrical HazardsLightning an electrical discharge which occurs between clouds and also from cloud to earth. Power contact / induction Acoustic Shock results from abnormally high sound level, the physical effects of which may vary from minor discomfort to serious injury. Electric Shock current through the body rather than voltage of the circuit determines electric shock intensity. Voltage is significant only in so far as it is one of the factors determining the magnitude of current.

The average resistance of a dry adult human body is approximately 1000 ohms. Wet or damaged skin reduces this figure and 1500 ohms is a conservative figure representing the body resistance for safety calculations.

Ventricular fibrillation is likely to occur when a 60Hz rms current of 0.030 amperes and above passes through ones chest cavity. Because of this, any circuit from which in excess of 30ma rms AC or 90ma DC can be drawn through a 1500 ohm resistor (45V RMS AC OR 135VDC) shall be classified as hazardous.

The potential difference at any time between any exposed structure (Equipment cabinets, Housings, Supports, etc.) to ground (Floor, Earth, etc.) or between any exposed structure within the reach of an adult person (Approx. 1.5 meters) shall be no greater than 45 volts rms AC or 135 volts DC.

The potential difference at any time between two points on the floor or earth surface separated by a distance of one pace, or about one meter, in the direction of maximum potential gradient shall be no greater than 45 volts rms AC or 135 volts DC.

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Protection MethodsShielding it is the provision of a grounded electrical conducting material located such that foreign potential will be intercepted and surge currents diverted to ground with the least damage to plant equipment possible. Voltage Limiting prevents development of hazardous potential difference in communication plant by direct bonding, when permissible or by use of surge arresters, discharge gaps, diodes, etc. which operate under abnormal voltage condition. Current Limiting and Interrupting current in a circuit can be kept from rising above a predetermined value by the use of a fuse in series with a circuit. When current flows through a fuse for a specified time with a magnitude greater than its rating, the fuse will interrupt the current. Grounding and Bonding used to divert undesired currents before they reach the equipment being protected and often are installed both at and some distance away from the protected equipment.

Ground Resistance it is the resistance path of a ground connection which includes the ground wire and its connection to ground electrode. The ground electrode, the contact between the electrode and the earth and the surrounding soil. This value should NEVEREXCEED 5.0 OHMS FOR EQUIPMENT LOCATIONS, ANTENNA TOWERS, AND ALL ALLIED INSTALLATIONS, AND 25 OHMS FOR OUTSIDE PLANT TELEPHONE POLES AND MANHOLES AS WELL AS CUSTOMER PREMISES.

Made Ground it is an electrode buried in the ground for the purpose of establishing a low resistance electrical contact with the earth. Example: driven rods, driven pipes, buried plates, buried cones, or other similar devices placed in the ground.

Methods and MaterialsLightning Rods is a metal strip or rod, usually of copper or similar conductive material, designed to protect tall or isolated structures (such as the roof of a building or the mast of a vessel) from lightning damage. Fuses and Current Interrupting - a device used in electrical systems to protect against excessive current.



Surge Arresters these are normally open circuited devices and pass no significant current at normal operating potentials. Grounding and Bonding - provides certain level of safety to humans and property in case of equipment damages.

MeasurementsGround Resistance Test Methods measurement procedures that is simple and straight forward and the instruments are mostly direct reading.

Methods for Ground Resistance Measurements Direct Method or two terminal test the simplest way to make an

earth resistance test. The fall of potential method or three terminal test Voltmeter-Ammeter Method Triangulation Method

Earth Resistivity it is the resistance of parallel faces of a one cubic centimeter of soil. Expressed in ohm-centimeter. Determining Good Electrode Location Drive rods in various locations to such depths as may be required

and measure the resistances while the rods are being driven. Measure the earth resistivity before driving ground rods then

calculate the number and length of rods required. How to Improve Grounds Lengthen the ground-electrode in the earth. Use multiple rods. Treat the soil when 1 & 2 are not feasible.

Maintenance and Inspection Grounding system requirements from year to year can change

depending on the following factors: A plant or facility can expand in size or change its operation and

such changes create different needs in the grounding system. As more non-metallic pipes and conduits are installed underground,

such installation becomes less and less dependable as effective low-resistance ground connections.

In many locations, the water table is gradually falling, and grounds formerly effective may end up uneffective.

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Ground resistance shall be tested when installed and periodically afterwards, at least once a year during the dry or non-rainy months and ALL VALUES OBTAINED SHALL BE NO GREATER THAN THE RULE REQUIRED. (See protection method).

All ground connections, be it solderless or soldered, shall be checked at least once a year to be sure they are tight. Physical damage to ground wires shall be checked at the same time and damages rectified or damaged conductors replaced.

Do not test grounds during thunderstorm days.

Never take hold of two wires or a wire or rod or probe in such a way that you complete a circuit through yourself.

Stray earth currents, accidental contacts or ground faults in the power system may produce an undeterminable difference of potential between two points, so use rubber gloves and handle ground wires under test as if they are energized.

GENERAL STRENGTH REQUIREMENTS

Loading ZonesHeavy Loading Zone this loading shall be taken as the resultant stress due to wind and dead weight for 240 kph wind velocity.

Medium Loading Zone - this loading shall be taken as the resultant stress due to wind and dead weight for 200 kph wind velocity.

Light Loading Zone - this loading shall be taken as the resultant stress due to wind and dead weight for 160 kph wind velocity.



POWER SOURCES

Storage Batteries and Chargers Batteries should be located where temperatures range between 15.5 and

32.2 degrees Celsius (60 degrees and 90 degrees Fahrenheit). Higher temperature will shorten battery life and lower temperature will decrease the ampere-hour capacity and may damage the battery by freezing especially when the batteries are in low state of charge.

Lead acid or similar gas emitting battery installations where the aggregate power (ampere-hour rating, at the 8-hour rate to 1.75 volts per cell multiplied by the battery voltage) exceeds 5 kilowatts shall be located in a properly ventilated room separated from the equipment room or location where people are staying.

Explosion resistant vents shall be provided for all lead acid or similar gas emitting batteries above 10 ampere-hour capacity and ascertained by periodic inspection that the vents are free from obstruction.

Ventilation of the battery room is very important especially during high charging and discharging condition. Although the battery is fitted with an explosion proof vent, an enclosed room could develop a sufficiently high concentration of an explosive gaseous mixture which could be ignited by sparks from adjacent electrical or electronic equipment as well as accidental sparks or open flame introduced by personnel. All air moved by ventilation in the battery room or area should be exhausted into the outside atmosphere and should not be allowed to recirculate into other confined areas.

Smoking and storing of inflammable materials is prohibited in battery rooms and NO SMOKING signs should be posted in conspicuous locations inside and before entering battery rooms.

Batteries, where the corrosive electrolyte maybe added in the field or customer location, transported by air or boat shall be shipped dry charged. They may be transported with electrolyte via land transportation provided electrolyte leakage or spillage are contained with its crate or carton and proper markers regarding handling precautions are clearly marked on its crate or carton.

Batteries on racks shall be provided with earthquake bracings which hold the sides of the batteries and prevent them from falling off the rack.

For noise consideration, grounds may have to be separated as one of the various possible means to help meet noise objectives and, in such

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case, the grounds may be insulated from each other except at the final point of earth connection at the master ground bar or earth electrode.

Power cables are sized to limit the voltage drop due to resistance of the cable and hole heating of the cables to a safe limit. The limits of minimum voltage are critical to the operation of the equipment; therefore, it is important that voltage drops in the cabling be carefully controlled.

Attempt should be made to limit the overall voltage drop from the battery to the working equipment to a maximum of one volt. The final selection of cable size should be generous since the calculation makes no allowance for voltage drop due to items such as fuses, switches, etc.

Various battery voltage may be derived by connecting a number of cells in series and in all cases the rule required is not violated. (See Electrical Hazards).

Frames of battery chargers, battery enclosures if provided, and all exposed metallic structures shall be bonded together and grounded, meeting the required rule. (See Electrical Hazards).

Caustic soda or either acid neutralizing agents should be stored and available in battery rooms for use in accidental electrolyte or acid spillage.



DEFINITION OF TERMS

Access a point of entry or a means of entry into a circuit

Accessible admitting close approach because not guarded by locked doors, elevation or other effective means.

Accessible part a part so located that it can be contacted by a person, either directly or by menas of a probe or tool, or that is not recessed the required distance behind an opening.

Accessories devices that perform a secondary or minor duty as an adjunct or refinement to the primary or major duty of a unit of equipment.

Acoustics the science of sound

Acoustic Shock the physical pain, dizzeness and sometimes nausea caused by hearing a sudden very loud sound. The threshold of pain is about 120 dBm.

Aging the change in properties of a material with time.

Air Gap a separating space between two magnetic materials or conductors.

Alarm a visual or audible signal which alerts personnel to the existence of an abnormal condition

Alive to have an electrical potential or charge different from that of the earth.

Alpeth a type of telephone cable sheath featuring a corrugated aluminium tape applied longitudinally and a polyethelene jacket overall.

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American Wire Gauge a scale of cross sectional measurement for non-ferrous (copper, bronze, aluminium, etc.) wires

Ampere-Hour the quantity of electricity represented by a current of one ampere that flows for one hour.

Anchor any device which holds something secure; a device buried in the ground to which anchor rods and guys are fastened.

Anhydrous Antenna dry; containing no water. A means for radiating or receiving radio waves.

Appliance any device that uses or needs electricity or usually an alectric current supply to perform a certain function or operation; any equipment, usually complete in itself, that transforms electric energy into another form usually, visual, heat, or motion at the point of utilization.

Arrester device which diverts high transient voltage to ground and away from the equipment thus protected; the voltage limiting portion of a protector.

Arrester Gas-Filled protector consisting of opposing spaced metal electrodes within a sealed tube or enclosure filled with gas such as neon or argon.

Assembly a grouping of components to accomplish a particular function

Atmosphere, Explosive air holding in suspension dust, metal particles or flammable gas in such proportions that may ignite explosively



Attachments all of the plant elements (cables, cross-arms,

brackets, etc) which are fastened to a supporting structure such as a pole.

Audio pertaining to frequencies which can be heard by the human ear.

Automatic describing the actions of a device or equipment which are taken without human supervision in response to certain pre-determined conditions.

Backbone the main system route, usually the route carrying the majority of the traffic, and often the longest series of cascaded hops.

Bandwith range of frequencies of a device, within which its performance, in respect to some characteristics conform to specified limits; the difference between the upper and lower limits of the operating frequency of the device.

Baseband band of frequencies occupied by the aggregate of all the information signals used to modulate a carrier.

Battery a group of two or more cells connected together to furnish current by conversion of chemical, thermal, solar or nuclear energy into electrical energy.

Bond a low resistance electrical connection between two cable sheaths, between two ground connections or between similar parts of two circuits.

Bus a conductor or group of conductors, that serve as a common connection for two or more circuits.

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Cable assembly of insulated conductors into a compact form which is covered by a flexible, waterproof, protective covering.

Circuit the complete electrical path between terminals over which telecommunications are provided.

Climbing Space the vertical space reserved along the side of a pole or tower to permit ready access for linemen to equipment and conductors located thereon.

Conductor anything such as a wire or cable which is suitable for the carrying of an electric current.

Communication transmitting and or receiving of information signals, or messages between two or more points.

dB abbreviation for decibel which is one-tenth of a bel. A unit expressing the ratio of two voltages, currents or powers. It is equal to 20 times the common logarithm of the ratio of the two voltages or two currents and 10 times the common logarithm of the ratio of the two powers.

Dropwire insulated wires, used to run a subscribers line from the terminal on the pole to the protector at the house or building.

Electronics the branch of science and technology which deals with the control and utilization of electron flow.

Electronic Switching the selective interconnection of channels of communication by means consisting essentially if not entirely of electronic circuitry and circuit elements.



Explosion proof one that is designed and constructed to withstand an explosion og a gas or vapour that may occur within it or in its immediate vicinity and to prevent the ignition of the gas or vapour surrounding or within its enclosure.

Exposed Part a part which can be inadvertently touched or approached nearer than a safe distance.

Facility anything used or available for use in the furnishing of communication service.

Facilities the elements used or available for use in the furnishing of communication service, such as radio facilities, outside plant facilities, indoor plant facilities, etc.

Fault a physical condition that causes a device, a component or a element to fail to perform in a required manner.

Fault current a current that flows from one conductor to ground or to another conductor owing to any abnormal connection (including an arc) between the two.

Flame Proof apparatus so treated such that it will not maintain a flame or will not be injured readily when subjected to flame.

Flame Retarding property of materials or structures such that they will not convey flame or continue to burn for longer times than specified in the appropriate flame test.

Flashover a discharge through air, around or over the surface of solid, liquid or other insulation, between parts of different potential of polarity, produced by

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the application of voltage such that the breakdown path becomes sufficiently ionized to maintain an electric arc.

Fuse a device used for protection against excessive currents. Consisting of a short length of fusible metal strip which melts when the current through it exceeds the rated amount for a definite time.

Ground a conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to earth, or to some conducting body of relatively large extent that serves in place of the earth.

Ground Bus a bus to which the grounds from individual pieces of equipment are connected, and, that, in turn, is connected to ground at one or more points.

Ground Ring a configuration of grounding conductors arrange around a structure such as building, tower footing, tower guy anchor etc. normally connected to an earth ground at one or more points.

Guy a tension member (of solid or stranded wires) used to withstand an otherwise unbalanced force on a pole or other overhead line structures.

Guy, Overhead a guy extending from a pole or structure or tree and is sometimes called a span guy.

Guy, Anchor a guy which has its lower anchorage in the earth.



Guy Exposed a guy which has any part less than 2.5 meters from the vertical plane of any electric power conductor of more than 250 volts.

Guy in Proximity a guy which has any part within a vertical distance of less than 2.5 meters from the level of power conductors and a radial distance of less than 1.8 meters from the surface of a wooden pole or structure.

Guarded covered, shielded, fenced, enclosed, or otherwise protected by means of suitable covers or casings, barrier rails or screens, or platform to remove the likelihood of dangerous contact with or approach by persons or objects to a point of danger.

Handhole an opening in an underground run or system into which workers reach, but do not enter. A sub-surface box having a cover flush with the ground.

Hazard any condition which imperils life, limb and property.

Insulated separated from other conducting surfaces by a dielectric substance or air space permanently offering a high resistance to the passage of current and to disruptive discharge through the substance or space. When any object is said to be insulated, it is understood to be insulated in suitable manner for the conditions to which it is subjected. Otherwise, it is, within the purpose of this code, uninsulated.

Joint Use occupancy of poles or structures by two or more different entities by mutual agreement.

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Lightning Arrester a device designed to protect apparatus from high transient voltage, by diverting surge current to ground and capable of repeating this function as specified.

Lines, Communication the channels or conductors and their supporting or containing components or structures usually located outdoors which are used for transmission/reception of information/intelligence in communication service (telephone, telegraph, data telemetering, video, etc.).

Lines, Power the conductors and their supporting or containing structures which are located outdoors used for transmitting a supply of electrical energy.

Maintenance all of the work required to keep the plant, circuits, lines, facilities, systems and services up to standards. This includes testing, trouble clearing, repairing, and replacing defective elements.

Manhole a subsurface chamber, large enough for a person to enter, in the route of one or more conduit runs, and affording facilities for placing and maintaining in the runs, conductors, cables and any associated apparatus.

Manual operated by mechanical force, applied directly by personal intervention.

Messenger stranded steel wires in a group which generally is not a part of the conducting system, its primary function being to support wires or cables of the system.



Noise any unwanted disturbance in a communication system which tends to obscure the clarity and validity of a signal in relation to its intended end use.

Operating Control a control, usually a knob, pushbutton or lever, provided to enable the user to cause the appliance to perform its intended function, without the use of tools, when the appliance is in normal operating condition.

Plant a general term applied to the whole or portion of the physical property of a communication company which contributes to the furnishing of communication service.

Plant, Inside all plant which is inside of buildings.

Plant, Outside all plant which is out of doors not in buildings, such as poles, conduits, cables, etc. installed overhead or underground.

Practicable capable of being accomplished by reasonably available and economic means.

Protector a device which provides protection from over-voltage and or over-current.

Protector, Carbon Block a protector whose voltage limiting element utilizes carbon blocks.

Protector, Gas Tube a protector whose voltage limiting element employs electrodes in a gas filled (neon, argon, etc.) envelope.

Qualified persons trained and authorized for the construction, maintenance and operation of the

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apparatus, circuit or system and responsible for the safety precautions involved.

Radiant Energy any energy which radiated in the form of radio waves, infrared (heat) waves, light waves, x-rays. etc.

Radiate the spreading out of radiant energy

Rod, Ground a metallic rod, driven into the ground to provide an electrical connection to the earth.

Rod, Lightning a metallic rod carried above the highest point of a pole or structure and connected to earth by a heavy copper conductor intended to carry lightning currents directly to earth.

Reconstruction that work which in any way changes the identity of the plant or station or portions thereof.

Service Drop the installation from the terminal on the pole to the protector at the customers premises.

Sag the maximum departure, measured vertically, of a wire or cable in a given span from a straight line between the two points of support of the span at 60 degrees celcius and no wind loading.

Span the horizontal distance between two adjacent supporting points of a cable or wire.

Supply Circuit the branch circuit supplying electrical energy to the equipment or appliance.

System, Electronic a configuration or arrangement of one or more electronic equipment producing the desired performance.



Telecommunication any transmission, emission or reception of signs,

signals, writings, images, sounds or intelligence of any nature by wire, radio, visual or other electromagnetic system or such other system that may in the future become known or developed.

Tensile Strength the pulling stress required to break a material, such as a wire, expressed in kilograms of stress per cross-sectional area.

Tension mechanical stress caused by forces which tend to stretch or severe the material stressed.

Tension, Maximum one-half of the tensile strength for messengers

Allowable guys, etc. and one-forth of the tensile strength for communication cables and wires.

Tower Displacement the horizontal displacement of a point on the tower axis from its no-wind load position at that elevation.

Tower Sway tower sway at any specified elevation shall be defined as the angular displacement of a tangent to the tower axis at the elevation from its no-wind load position at that elevation.

Tower Twist the horizontal angular displacement of the tower from its no-wind position at that elevation.

Underground describing communication facilities installed below the surface of the earth.

Working Space the space extending laterally from the climbing space, reserved for working below, above and between conductor levels; the space surrounding a device or equipment.

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1. An electrical discharge which occurs between clouds and also from cloud to earth.

A. Thunder B. Lightning C. Corona D. Aurora

2. Results from abnormally high sound level, the physical effects of which may vary from minor discomfort to serious injury.

A. Electrical Shock B. Super Sonic C. Acoustic Shock D. Sonic Boom

3. The factor that determines the intensity of electric shock is

A. current B. voltage C. resistance D. conductance

4. The average resistance of a dry adult human body is approximately:

A. 10 000 ohms B. 100 000 ohms C. 1 000 ohms D. 100 ohms

5. Ventricular fibrillation is likely to occur when a 60Hz rms current of _____amperes and above passes through ones chest cavity.

A. 0.010 B. 0.11 C. 0.030 D. 0.33



6. The minimum voltage value that is considered hazardous is:

A. 45V RMS AC B. 12V RMS AC C. 24V RMS AC D. 50V RMS AC

7. The minimum voltage value that is considered hazardous is:

A. 150V DC B. 45V DC C. 135V DC D. 160V DC

8. The potential difference at any time between two points on the floor or earth surface separated by a distance of one pace, or about one meter, in the direction of maximum potential gradient shall be no greater than _______.

A. 45 volts rms AC or 135 volts DC B. 25 volts rms AC or 115 volts DC C. 15 volts rms AC or 105 volts DC D. 55 volts rms AC or 145 volts DC

9. It is the provision of a grounded electrical conducting material located such that foreign potential will be intercepted and surge currents diverted to ground with the least damage to plant equipment possible.

A. Grounding B. Shielding C. Bonding D. current limiting

10. Prevents development of hazardous potential difference in communication plant by direct bonding, when permissible or by use of surge arresters, discharge gaps, diodes, etc. which operate under abnormal voltage condition.

A. Current limiting B. Resistance limiting C. Grounding D. Voltage Limiting

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11. The current in a circuit can be kept from rising above a predetermined value by the use of a fuse in series with a circuit.


12. This is used to divert undesired currents before they reach the equipment being protected and often are installed both at and some distance away from the protected equipment.


13. It is the resistance path of a ground connection which includes the ground wire and its connection to ground electrode.

A. Ground Resistance B. Ground Electrode C. Ground Path D. Resistance Path

14. For equipment locations, antenna towers, and all allied installations, the ground resistance must never exceed ______.

A. 25 ohms B. 3 ohms C. 43 ohms D. 5 ohms

15. For outside plant telephone poles and manholes as well as customer premises, the ground resistance must never exceed _____.

A. 25 ohms B. 3 ohms C. 43 ohms D. 5 ohms


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16. It is an electrode buried in the ground for the purpose of establishing a low resistance electrical contact with the earth. A. Ground pole B. Lightning Rods C. Guy D. Made Ground

17. It is a metal strip or rod, usually of copper or similar conductive material, designed to protect tall or isolated structures (such as the roof of a building or the mast of a vessel) from lightning damage.

A. Ground pole B. Lightning Rods C. Guy D. Made Ground

18. A device used in electrical systems to protect against excessive current.

A. fuse B. Lightning rod C. Surge arrester D. Grounding

19. These are normally open circuited devices and pass no significant

current at normal operating potentials.

A. fuse B. Lightning rod C. Surge arrester D. Grounding

20. Provides certain level of safety to humans and property in case of equipment damages.

A. fuse B. Lightning rod C. Surge arrester D. Bonding or grounding

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21. The simplest way to make an earth resistance test is to use:

A. Direct Method or two terminal test * B. Voltmeter-Ammeter Method C. Triangulation Method D. Three terminal test

22. It is the resistance of parallel faces of a one cubic centimeter of soil expressed in ohm-centimeter.

A. Ground resistance B. Earth Resistivity C. Cubic resistance D. Earth density

23. The following are ways to improve grounds except:

A. Lengthen the ground-electrode in the earth B. Use multiple rods C. Treat the soil when 1 & 2 are not feasible D. Place stones near the rod

24. Ground resistance shall be tested when installed and periodically afterwards, at least _____ during the dry or non-rainy months and ALL VALUES OBTAINED SHALL BE NO GREATER THAN THE RULE REQUIRED.

A. 3 times per year B. twice as year C. once a year D. 12 times a year

25. All ground connections, be it solderless or soldered, shall be checked at least ____ to be sure they are tight.

A. 3 times per year B. twice as year C. once a year D. 12 times a year



26. This loading shall be taken as the resultant stress due to wind and dead weight for 240 kph wind velocity.

A. Heavy Loading Zone B. Medium Loading Zone C. Light Loading Zone D. Extra Heavy Loading Zone





29. Batteries should be located where temperatures range between _______degrees Celsius.

A. 12.5 and 25.2 B. 15.5 and 32.2 C. 15.2 and 52.2 D. 55.5 and 60.3

30. Lead acid or similar gas emitting battery installations where the aggregate power exceeds ______5 kilowatts shall be located in a properly ventilated room separated from the equipment room or location where people are staying.

A. 5 kW B. 10 kW C. 1 kW D. 15 kW

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31. Smoking and storing of inflammable materials is prohibited in battery rooms and NO SMOKING signs should be posted _____.

A. inside the room only B. before entering battery rooms C. outside the room only D. Both A and C

32. An acid neutralizing agentsuch as _____ should be stored and available in battery rooms for use in accidental electrolyte or acid spillage.

A. oil B. kerosene C. flour D. Caustic soda

33. A low resistance electrical connection between two cable sheaths, between two ground connections or between similar parts of two circuits.

A. Bond B. Short C. Fuse D. Guy

34. The vertical space reserved along the side of a pole or tower to permit ready access for linemen to equipment and conductors located thereon.

A. Stairway B. Climbing Space C. guy D. pole

35. Insulated wires, used to run a subscribers line from the terminal on the pole to the protector at the house or building.

A. main line B. main cable C. dropline D. dropwire



36. A physical condition that causes a device, a component or a element to fail to perform in a required manner.

A. damaged B. hazard C. fault D. short

37. A current that flows from one conductor to ground or to another conductor owing to any abnormal connection (including an arc) between the two. A. Fault current B. Dark current C. Leakage current D. Dead short

38. An apparatus so treated such that it will not maintain a flame or will not be injured readily when subjected to flame.

A. Flame Proof B. Flame Retarding C. Burn proof D. Anti Flame

39. A property of materials or structures such that they will not convey flame or continue to burn for longer times than specified in the appropriate flame test.

A. Flame Proof B. Flame Retarding C. Burn proof D. Anti Flame

40. A discharge through air, around or over the surface of solid, liquid or other insulation, between parts of different potential of polarity, produced by the application of voltage such that the breakdown path becomes sufficiently ionized to maintain an electric arc. A. Aurora B. Corona C. Flashover D. Arc

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41. A conducting connection, whether intentional or accidental, by which an electric circuit or equipment is connected to earth, or to some conducting body of relatively large extent that serves in place of the earth.

A. short B. jumper C. ground D. link

42. A tension member (of solid or stranded wires) used to withstand an otherwise unbalanced force on a pole or other overhead line structures.

A. Bond B. Short C. Fuse D. Guy

43. A guy extending from a pole or structure or tree and is sometimes called a span guy.

A. Overhead guy B. Anchor guy C. bla guy D. Guy post

44. An opening in an underground run or system into which workers reach, but do not enter.

A. Manhole B. Rathole C. Handhole D. finger hole

45. A device designed to protect apparatus from high transient voltage, by diverting surge current to ground and capable of repeating this function as specified.

A. Lightning ball B. Lightning Arrester C. Fuse D. Lightning Protector



46. A subsurface chamber, large enough for a person to enter, in the route of one or more conduit runs, and affording facilities for placing and maintaining in the runs, conductors, cables and any associated apparatus.

A. Manhole B. Rathole C. Handhole D. finger hole

47. Stranded steel wires in a group which generally is not a part of the conducting system, its primary function being to support wires or cables of the system.

A. guy B. support C. conduit D. messenger

48. A general term applied to the whole or portion of the physical property of a communication company which contributes to the furnishing of communication service.

A. zone B. area C. plant D. division

49. A metallic rod, driven into the ground to provide an electrical connection to the earth.

A. Lightning rod B. Ground rod C. Drop ground D. radials

50. A metallic rod carried above the highest point of a pole or structure and connected to earth by a heavy copper conductor intended to carry lightning currents directly to earth. A Lightning arrester B. Lightning rod C. Breaker D. Lightning gap

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51. The installation from the terminal on the pole to the protector at the customers premises.

A. Service drop B. Subscribers loop C. Main line D. Local drop

52. The horizontal displacement of a point on the tower axis from its no-wind load position at that elevation.

A. Tower displacement B. Tower sway C. Tower Twist D. Tower bend

53. The angular displacement of a tangent to the tower axis at the elevation from its no-wind load position at that elevation.


54. The horizontal angular displacement of the tower from its no-wind position at that elevation.


55. Refers to communication facilities installed below the surface of the earth.

A. underneath B. underground C. earth mat D. under earth

2. Philippine Electronics Code - Volume 1

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Transcript of 2. Philippine Electronics Code - Volume 1