Electrical Conductor Types PDF

Electrical Conductor Types Answers 1. What is the minimum vertical clearance required for primary lines when crossing a highway? A. 12 m B. 5 m C. 10 m D. 7.5 m Answer: 10 m (C) Primary lines must maintain a minimum vertical clearance of 10 m when crossing highways to ensure safet...

Electrical Conductor Types Answers 1. What is the minimum vertical clearance required for primary lines when crossing a highway? A. 12 m B. 5 m C. 10 m D. 7.5 m Answer: 10 m (C) Primary lines must maintain a minimum vertical clearance of 10 m when crossing highways to ensure safety. 2. Where should poles be located in relation to the road right-of-way or property line? A. 500 mm inside the road right-of-way B. At the center of the road right-of-way C. 1 m from the property line D. At the edge of the road Answer: 500 mm inside the road right-of-way (A) Poles and transformer supports should be located no more than 500 mm inside the road right-of-way. 3. What is a requirement for the location of poles and transformer supports along public roads? A. They must not obstruct pedestrian paths B. They may obstruct sidewalks C. They are allowed within the drainage canal D. They can be placed anywhere along the road Answer: They must not obstruct pedestrian paths (A) Poles and transformer supports must not obstruct sidewalks or pedestrian paths. 4. Which of the following is NOT a consideration for the installation of overhead transmission lines? A. Public safety B. Location of electric meter C. Visual pollution D. Good viewing and aesthetics Answer: Location of electric meter (B) While visual pollution, public safety, and aesthetics are key considerations, the location of the electric meter is not mentioned. 5. What is the minimum vertical clearance for primary lines along the side of a highly urbanized area? A. 5 m B. 8 m C. 7.5 m D. 10 m Answer: 7.5 m (C) When installed along the side of a highly urbanized area, primary lines must maintain a minimum vertical clearance of 7.5 m. 6. What happens to the heat generated in a conductor placed in an enclosed conduit compared to when it is in free air? A. It is held in place and does not dissipate. B. It increases significantly due to higher resistance. C. It dissipates more easily. D. It dissipates at the same rate. Answer: It is held in place and does not dissipate. (A) Heat generated in enclosed conduits is not as easily dissipated as when in free air. 7. Which type of cable is known for its highly compressed refractory mineral insulation? A. Flat Cable Assemblies B. Non-Metallic Sheathed Cable C. Underground Feeder Cable D. Mineral Insulated Cable Answer: Mineral Insulated Cable (D) Mineral Insulated Cable (Type MI) is recognized for its compressed refractory mineral insulation. 8. What characterizes Non-Metallic Sheathed Cable (Type NM or NMC)? A. It has a metal sheath that is moisture resistant. B. It includes multiple conductors with a flame retardant outer sheath. C. It uses mineral insulation for high temperature applications. D. It is designed specifically for underground wiring. Answer: It includes multiple conductors with a flame retardant outer sheath. (B) Non-Metallic Sheathed Cable (Type NM or NMC) features multiple insulated conductors with a flame retardant outer sheath. 9. Which type of cable is specifically designed for field installation in square structural channels? A. Mineral Insulated Cable B. Shielded Non-Metallic Sheathed Cable C. Flat Cable Assemblies D. Service Entrance Cable Answer: Flat Cable Assemblies (C) Flat Cable Assemblies (Type FC) are intended for field installation in square structural channels. 10. What is the function of the moisture-resistant cable known as Type UF? A. It is primarily used in industrial settings. B. It is used for overhead power lines. C. It serves as an insulation layer for wires. D. It is intended for underground connections including direct burial. Answer: It is intended for underground connections including direct burial. (D) Type UF cable is moisture resistant and is suitable for underground connections, including direct burial. 11. What distinguishes Flat Conductor Cable (Type FCC)? A. It consists of flat copper conductors arranged edge to edge. B. It is wrapped in mineral insulation. C. It is a single conductor cable. D. It has a reinforced metal exterior. Answer: It consists of flat copper conductors arranged edge to edge. (A) Flat Conductor Cable (Type FCC) consists of multiple flat copper conductors placed edge to edge. 12. What type of cable encapsulates insulated conductors in an extruded core of moisture resistant and flame retardant material? A. Flat Cable Assemblies B. Mineral Insulated Cable C. Service Entrance Cable D. Shielded Non-Metallic Sheathed Cable Answer: Shielded Non-Metallic Sheathed Cable (D) Shielded Non-Metallic Sheathed Cable (Type SNM) features insulated conductors encased in moisture resistant and flame retardant material. 13. Which type of cable is best characterized as having a continuous copper sheath? A. Mineral Insulated Cable B. Flat Cable Assemblies C. Underground Feeder and Branch Circuit Cable D. Non-Metallic Sheathed Cable Answer: Mineral Insulated Cable (A) Mineral Insulated Cable has a continuous copper sheath which ensures proper sealing and insulation. 14. What is one advantage of flexible metal conduit wiring over rigid metal conduits? A. Requires more labor for installation B. More expensive to install C. Shorter lengths available D. Installation is easier and quicker Answer: Installation is easier and quicker (D) Flexible metal conduit wiring is easier and quicker to install compared to rigid metal conduits. 15. What material covers armored cable wiring to provide protection? A. Wooden shell B. Plastic casing C. Fiber optic layer D. Rubber or thermoplastic Answer: Rubber or thermoplastic (D) Armored cable wiring is covered with rubber or thermoplastic for protection. 16. What type of wiring consists of a factory-assembled channel with conductors for two to four circuits? A. Floor raceways B. Cable tray/open raceway C. Surface metal raceway D. Lighting track Answer: Lighting track (D) Lighting track is a factory-assembled channel that accommodates two to four circuits. 17. In surface metal raceway wiring, how are the wires supported? A. Suspended from the ceiling B. On a thin sheet metal casing C. Embedded within concrete walls D. Internally within insulated tubing Answer: On a thin sheet metal casing (B) In surface metal raceway wiring, the wires are supported on a thin sheet steel casing. 18. What is the maximum length for flexible metal conduit wiring? A. 10 ft. B. 25 ft. C. 150 ft. D. 250 ft. Answer: 250 ft. (D) Flexible metal conduit wiring can come in lengths from 25 ft to 250 ft depending on the size. 19. What types of cables must be used when a cable tray/open raceway is functioning as a general wiring system? A. Metal conduits only B. Unjacketed cables C. Ribbon cables D. Self-protected, jacketed types Answer: Self-protected, jacketed types (D) Cables used in a cable tray/open raceway as a general wiring system must be of self-protected, jacketed types. 20. Which type of raceway is recognized by NEC as having underfloor ducts? A. Floor raceways B. Ceiling raceway systems C. Flexible metal conduit D. Surface metal raceway Answer: Floor raceways (A) The NEC recognizes floor raceways, which include underfloor ducts installed beneath the floor. 21. What is a characteristic of ceiling raceway systems? A. They must be embedded in walls B. They have separate header and distribution ducts for power and telephone cabling C. They are only used for heavy-duty circuits D. The raceway must not be mounted on walls Answer: They have separate header and distribution ducts for power and telephone cabling (B) Ceiling raceway systems consist of header ducts and distribution ducts that are separate for power and telephone cabling. 22. What is the minimum vertical clearance requirement for secondary, neutral, and service lines when crossing the highway? A. 2.4 m B. 5 m C. 7.5 m D. 10 m Answer: 7.5 m (C) Secondary, neutral, and service lines must maintain a minimum vertical clearance of 7.5 m when crossing highways. 23. What is the minimum distance that a pole must maintain from a fire hydrant? A. 10 m B. 150 mm C. 5 m D. 2.4 m Answer: 5 m (C) Poles must be located at least 5 m away from fire hydrants. 24. What is the minimum vertical clearance from the crown of the road pavement for poles when installed along the highway? A. 10 m B. 2.4 m C. 500 mm D. 7.5 m Answer: 7.5 m (D) Poles must maintain a minimum vertical clearance of 7.5 m from the crown of the road pavement. 25. When overhead lines are arranged for buildings exceeding 15 m in height, what is the minimum required clear space for ladder access? A. 3 m B. 1 m C. 2 m D. 2.5 m Answer: 2 m (C) A clear space of at least 2 m is required adjacent to the building for ladder access. 26. What minimum distance must be maintained from the curb for poles? A. 200 mm B. 1 m C. 5 m D. 150 mm Answer: 150 mm (D) Poles must be positioned at least 150 mm away from the curb. 27. In a highly urbanized area, what minimum clearance must be observed when installing lines along the street? A. 10 m B. 7.5 m C. 2.4 m D. 500 mm Answer: 7.5 m (B) A minimum vertical clearance of 7.5 m is required for lines installed along streets in highly urbanized areas. 28. What requirement exists for power lines attached to buildings? A. They should be installed at 2.4 m height. B. They must be placed no closer than 5 m from the street. C. They must be at least 10 m from fire hydrants. D. They need an Approved Attachment Plan. Answer: They need an Approved Attachment Plan. (D) Attachments for support of power lines and similar equipment must be covered by an Approved Attachment Plan. 29. What should be avoided when positioning poles and towers near street corners? A. Positioning them less than 500 mm from the curb B. Making them inaccessible from poles C. Setting them 5 m away from hydrants D. Installing them more than 10 m from the road Answer: Making them inaccessible from poles (B) Poles and towers should not be positioned too far from street corners to avoid inaccessible setups for flying taps. 30. What is the minimum thickness required for walls of vaults constructed from reinforced concrete? A. 150mm B. 100mm C. 300mm D. 200mm Answer: 150mm (A) Walls of vaults must be constructed of reinforced concrete that is not less than 150mm thick. 31. Which type of material is acceptable for constructing the ducts for ventilation? A. Metal sheets B. Plastic tubing C. Wooden planks D. Fire resistant material Answer: Fire resistant material (D) Ventilating ducts must be constructed of fire resistant material to ensure safety. 32. What is the minimum requirement for a door sill or curb within the vault? A. 75mm B. 150mm C. 100mm D. 50mm Answer: 100mm (C) The door sill or curb must be of sufficient height to confine oil and shall not be less than 100mm. 33. How thick should the coating on the inside wall surface of hollow concrete block vaults be? A. 10mm B. 25mm C. 15mm D. 20mm Answer: 20mm (D) The inside wall surface of vaults made of hollow concrete blocks should have a coating of at least 20mm. 34. What should be ensured regarding the location of ventilation openings? A. Far away from doors and combustible materials B. Above the roof line C. Near windows D. Close to fire escapes Answer: Far away from doors and combustible materials (A) Ventilation openings must be located as far away as possible from doors, windows, fire escapes, and combustible materials. 35. Which of the following is an essential feature of entrance doors for vaults? A. They must open outward. B. They must be decorative. C. They should be fitted with windows. D. They should be equipped with locks. Answer: They should be equipped with locks. (D) Entrance doors must be equipped with locks and should be locked unless access is permitted. 36. What is the minimum fire resistance required for construction materials used in vaults? A. Two hours B. Two and a half hours C. One hour D. Three hours Answer: Two and a half hours (B) Building materials for vaults must have a minimum fire resistance of two and a half hours. 37. How is ventilation of vaults typically achieved? A. By natural circulation of air B. Through mechanical systems only C. By direct electrical cooling D. Using only flues Answer: By natural circulation of air (A) Vaults may be ventilated by natural circulation of air, which is a key design feature.