Download Florida County Elevator Electrical Exam Questions and Answers and more Exams Technology in PDF only on Docsity!
Question 1. Which Florida Building Code chapter specifically governs elevators and conveying systems? A) Chapter 20 B) Chapter 30 C) Chapter 40 D) Chapter 50 Answer: B Explanation: Chapter 30 of the Florida Building Code (FBC) contains the mandatory requirements for elevators and other conveying equipment. Question 2. Under ASME A17.1, what is the minimum illumination level required for the machine‑room work platform? A) 5 lux B) 10 lux C) 20 lux D) 30 lux Answer: C Explanation: A17.1 mandates at least 20 lux (2 ft‑candle) on any work platform in the machine room to ensure safe maintenance activities. Question 3. NEC Article 620 modifies the general feeder sizing rules for elevators. Which demand factor is applied to the first 5 kW of motor load? A) 100 % B) 75 % C) 50 % D) 25 % Answer: A Explanation: The first 5 kW of elevator motor load is taken at 100 % demand; additional loads receive reduced demand factors per NEC 620.11.
Question 4. Which device is required by NEC 620.91 to prevent operation of the elevator when the phase sequence is reversed? A) Ground‑fault interrupter B) Phase‑reversal relay C) Over‑current protective device D) Surge protector Answer: B Explanation: A phase‑reversal relay detects incorrect phase order and disables the elevator controller to protect the motor. Question 5. In a hydraulic elevator, which component’s electrical supply must be protected by a dedicated GFCI receptacle in the machine room? A) Pump motor starter B) Control valve solenoid C) Door operator D) Lighting circuit Answer: A Explanation: The pump motor starter is a high‑current, wet‑area load; NEC requires a GFCI receptacle for such equipment in machine rooms. Question 6. What is the purpose of the safety string in an elevator system? A) Provide a communication link between car and pit B) Series‑connect all safety devices so loss of any opens the circuit C) Supply power to the car lighting circuit D) Act as a backup power source for emergency operation Answer: B Explanation: The safety string interconnects devices such as limit switches, governor, and door contacts; an open anywhere disables motion. Question 7. Which of the following is a permitted conduit type for hoist‑way wiring according to NEC 620?
B) Phase II – Firefighter’s operation C) Phase III – Emergency power D) Phase IV – Automatic return Answer: B Explanation: Phase II fire‑service operation allows firefighters to control the car, typically recalling it to the lobby with doors open for rescue. Question 11. According to ASME A17.1, what is the minimum clearance required between the hoist‑way wall and the nearest exposed live part? A) 1 in. B) 2 in. C) 4 in. D) 6 in. Answer: C Explanation: A minimum of 4 in. clearance is required to prevent accidental contact with live parts in the hoist‑way. Question 12. Which NEC article governs the installation of emergency‑power supplies for elevator lighting? A) Article 700 B) Article 620 C) Article 210 D) Article 240 Answer: B Explanation: NEC 620 includes provisions for emergency lighting circuits specific to elevators, superseding the general emergency‑power rules. Question 13. In a relay‑logic control panel, which relay typically provides the “car‑at‑floor” indication? A) Holding relay B) Call‑register relay
C) Position‑feedback relay D) Door‑interlock relay Answer: C Explanation: The position‑feedback (or floor‑indicator) relay closes when the car reaches a specific floor, providing the “car‑at‑floor” signal. Question 14. Which of the following is NOT a permitted method for routing traveling cables in the hoist‑way? A) Through a dedicated cable tray B) Inside a flexible metal conduit that follows the car guide rails C) Hanging loosely from the ceiling without support D) Within a protective conduit looped around the guide rails Answer: C Explanation: Traveling cables must be supported and protected; hanging loosely is prohibited due to abrasion and vibration risks. Question 15. What is the correct NEC temperature correction factor for conductors in a machine room rated at 40 °C (104 °F)? A) 0. B) 0. C) 1. D) 1. Answer: A Explanation: NEC Table 310.15(B)(2)(a) gives a 0.91 correction factor for 40 °C ambient temperature. Question 16. Which component detects overspeed conditions and initiates a safety stop? A) Final limit switch B) Pit switch C) Speed governor with a centrifugal switch D) Door‑lock contact
Explanation: Car‑call buttons are simple on/off contacts, thus a digital input module is used. Question 20. Which of the following is the correct sequence for energizing an elevator’s main disconnect during startup? A) Close main disconnect, then close controller disconnect, then energize VFD B) Close controller disconnect, then main disconnect, then VFD C) Energize VFD first, then close all disconnects D) Close all disconnects simultaneously Answer: A Explanation: The main service disconnect must be closed first to supply power, followed by the controller disconnect, and finally the VFD is energized. Question 21. The NEC requires a minimum of how many grounding conductors for a three‑phase elevator motor? A) One grounding conductor per phase B) One equipment grounding conductor only C) Two separate grounding conductors D) No grounding conductor if the motor is double‑insulated Answer: B Explanation: NEC permits a single equipment grounding conductor to protect all phases of a three‑phase motor. Question 22. What is the purpose of a “phase‑loss” relay in an elevator control system? A) Detect and isolate a broken conductor in a three‑phase supply B) Provide over‑current protection for the motor C) Switch the elevator to emergency power automatically D) Balance the load between phases Answer: A Explanation: A phase‑loss relay monitors each phase; loss of any phase trips the relay to prevent motor damage.
Question 23. Which of the following statements about the “car‑top operating station” (CTOS) is correct? A) It provides a permanent power source for the car’s lighting. B) It is used only for routine inspections and never for emergency operation. C) It includes a local disconnect and control switches for maintenance. D) It must be located outside the hoist‑way. Answer: C Explanation: The CTOS contains a local disconnect and control switches that allow safe maintenance and emergency operation from the car top. Question 24. According to ASME A17.1, what is the minimum required rating for the emergency‑operation alarm bell? A) 70 dB at 3 ft B) 80 dB at 3 ft C) 90 dB at 3 ft D) 100 dB at 3 ft Answer: C Explanation: The code mandates an audible alarm of at least 90 dB measured at 3 ft to alert occupants during emergency operation. Question 25. When sizing a feeder for a traction‑elevator motor of 20 kW at 480 V, 3‑phase, what is the approximate ampacity before applying demand factors? A) 15 A B) 25 A C) 35 A D) 45 A Answer: B Explanation: Using (I = P / (\sqrt{3} \times V \times PF)) with PF≈0.9 gives ≈24 A; rounded to the next standard size yields a 25 A conductor.
A) Article 210. B) Article 625 C) Article 210. D) Article 620. Answer: D Explanation: Article 620.53 specifically addresses receptacles and lighting in the elevator car and hoist‑way. Question 30. What is the primary function of the “door‑interlock” relay in an elevator control circuit? A) Provide power to the door motor B) Prevent car movement when any door is open C) Signal the fire‑service operation panel D) Control the car’s interior lighting Answer: B Explanation: The door‑interlock relay opens the safety string when a door is not fully closed, stopping car motion. Question 31. Which of the following is a required test for the safety‑string continuity during routine maintenance? A) Insulation resistance test > 1 MΩ B) Continuity test showing < 0.5 Ω total resistance C) Voltage drop test under load D) No test is required if the string is visually intact. Answer: B Explanation: The safety string must have low resistance (< 0.5 Ω) to ensure reliable operation of all interlocked devices. Question 32. Under NEC 620.71, what is the minimum size of the grounding electrode conductor for a 400 ‑A elevator service? A) #12 AWG copper
B) #10 AWG copper C) #8 AWG copper D) #6 AWG copper Answer: D Explanation: NEC Table 250.66 requires a #6 AWG copper grounding electrode conductor for services 351 A – 600 A. Question 33. Which of the following motor types typically requires a regenerative drive for energy recovery? A) AC induction motor B) DC shunt motor C) Permanent‑magnet synchronous motor (PMSM) D) Synchronous reluctance motor Answer: C Explanation: PMSM drives can regenerate power during deceleration, feeding it back to the supply. Question 34. When installing a new emergency‑operation battery bank for an elevator, which code requires the battery enclosure to be fire‑rated? A) NFPA 70 (NEC) B) NFPA 72 (Fire Alarm) C) ASME A17. D) OSHA 1910. Answer: A Explanation: NEC 480.24 requires fire‑rated enclosures for battery banks used in emergency power systems. Question 35. Which of the following is the correct method to protect a VFD control cabinet from harmonic distortion? A) Install a line‑reactor at the input. B) Use a larger feeder conductor only.
D) It only applies to single‑phase equipment. Answer: B Explanation: Many manufacturers offer a combined phase‑reversal and overload relay, satisfying both requirements with one device. Question 39. According to ASME A17.1, how many independent safety devices must be present in the safety‑string for a traction elevator? A) One B) Two C) Three D) Four Answer: C Explanation: The code requires at least three independent devices (e.g., pit switch, governor, door interlock) in series. Question 40. Which NEC article governs the installation of conduit in a pit that is subject to flooding? A) Article 300. B) Article 310. C) Article 625 D) Article 210. Answer: A Explanation: Article 300.5 addresses protection of wiring methods in areas prone to moisture or flooding, such as elevator pits. Question 41. When retrofitting an older elevator to meet the latest NEC 2020 requirements, which of the following is typically required? A) Replacement of all lighting with LED fixtures only B) Installation of a dedicated grounding conductor for the control cabinet C) Removal of all VFDs and replacement with direct‑on‑line starters D) Elimination of all emergency‑operation circuits
Answer: B Explanation: Modern code requires a dedicated equipment grounding conductor for control cabinets, even in retrofits. Question 42. The “final limit switch” is positioned where in an elevator system? A) At the top of the hoist‑way B) At the bottom of the car shaft, just above the pit floor C) Inside the machine‑room motor housing D) On the car ceiling panel Answer: B Explanation: The final limit switch is installed near the pit floor to stop the car at the lowest landing. Question 43. Which of the following is a required feature of the emergency‑operation switch in an elevator? A) Must be a push‑button with a red cover. B) Must be a two‑pole, lock‑out type that disconnects all power. C) Must be located only in the machine room. D) Must be operable with a key or padlock. Answer: B Explanation: The emergency‑operation switch must isolate the entire power source, typically a two‑pole lock‑out device. Question 44. Under NEC 620.44, what is the maximum permissible voltage for a low‑voltage elevator control circuit? A) 30 V AC or DC B) 50 V AC or DC C) 75 V AC or DC D) 120 V AC only Answer: A Explanation: Low‑voltage control circuits are limited to 30 V (or 30 V DC) to reduce shock hazard.
Question 48. In a PLC‑controlled elevator, what does the “watchdog timer” function protect against? A) Over‑temperature of the motor B) Loss of communication with the floor‑position sensors C) Software lock‑up causing loss of control D) Excessive current draw on the power bus Answer: C Explanation: The watchdog timer resets the PLC if the program stops responding, preventing uncontrolled elevator motion. Question 49. Which of the following statements about “ground‑fault protection of equipment” (GFPE) is correct for elevator installations? A) Required on all 120 V circuits in the machine room. B) Required only on circuits that supply the car lighting. C) Not required if the equipment is double‑insulated. D) Required on all 240 V motor circuits serving the hoist. Answer: D Explanation: NEC 620.61 requires GFPE on motor circuits that are 250 V or less and serve the hoist, to protect personnel. Question 50. The NEC requires that all elevator‑room disconnecting means be mounted at a height not exceeding what maximum? A) 6 ft above the floor B) 7 ft above the floor C) 8 ft above the floor D) 9 ft above the floor Answer: B Explanation: NEC 620.71 specifies that disconnects must be installed at a maximum of 7 ft above the floor for accessibility.
Question 51. Which of the following is the correct method to calculate the feeder size for an elevator with a motor demand of 12 kW, 480 V, 3‑phase, assuming a 0.9 power factor? A) Use 125 % of full‑load amps per NEC 430. B) Apply NEC 620 demand factor of 0.8 to the motor load only C) Size based on 100 % of the calculated current without derating D) Use the NEC 310 ampacity table for 75 °C conductors after applying temperature correction Answer: D Explanation: After computing current (≈15 A), the conductor is selected from Table 310 using the appropriate temperature correction; demand factors are applied separately. Question 52. Under ASME A17.1, which device must be installed to provide a visual indication that the elevator is in fire‑service mode? A) Red strobe light on the car top B) “FIRE SERVICE” illuminated sign in the car panel C) Flashing beacon on the machine‑room ceiling D) None; only audible signals are required Answer: B Explanation: A visible “FIRE SERVICE” indication is required to alert occupants and responders that fire‑service operation is active. Question 53. Which NEC article specifically addresses the installation of conduit and wiring in elevator hoist‑ways? A) Article 300. B) Article 620. C) Article 410. D) Article 725. Answer: B Explanation: Article 620.52 provides the rules for raceways and wiring methods within hoist‑ways and machine rooms. Question 54. What is the purpose of a “travel‑limit switch” in an elevator?
B) 50 V AC only C) 75 V DC only D) 120 V AC Answer: A Explanation: NEC 625 defines low‑voltage elevator control circuits as not exceeding 30 V (rms AC or DC). Question 58. Which of the following is the correct order of operation for a fire‑service recall sequence? A) Activate fire‑service switch → Open all doors → Move car to lobby → Open doors B) Activate fire‑service switch → Close doors → Move car to lobby → Open doors C) Close doors → Activate fire‑service switch → Move car to lobby → Open doors D) Move car to lobby → Activate fire‑service switch → Close doors → Open doors Answer: B Explanation: The fire‑service switch initiates recall, doors must be closed for safe movement, then the car returns to the lobby and doors open for egress. Question 59. Which NEC requirement applies to the grounding of the elevator’s steel guide rails? A) Must be bonded to the building’s grounding electrode system at each floor. B) Must be bonded at the top of the hoist‑way only. C) Must be bonded to the motor frame only. D) No bonding required if the rails are painted. Answer: A Explanation: Guide rails must be bonded to the building grounding system at each floor to prevent stray voltage. Question 60. In a traction elevator, the “overspeed governor” is typically calibrated to trip at what percentage above rated speed? A) 105 % B) 110 % C) 125 %
D) 150 %
Answer: C Explanation: Governors are set to trip at approximately 125 % of the rated speed to provide a safety margin. Question 61. Which of the following is the correct NEC designation for a conduit system used to protect power conductors in a machine‑room that is exposed to corrosive environments? A) RMC (Rigid Metal Conduit) B) PVC (Polyvinyl Chloride) conduit C) EMT (Electrical Metallic Tubing) D) LFNC (Liquid‑tight Flexible Non‑metallic Conduit) Answer: D Explanation: LFNC provides a sealed, corrosion‑resistant path suitable for harsh machine‑room conditions. Question 62. What is the minimum size of the grounding electrode conductor required for a 600 A elevator service according to NEC Table 250.66? A) #6 AWG copper B) #4 AWG copper C) #2 AWG copper D) #1/0 AWG copper Answer: B Explanation: For services 601 A – 800 A, Table 250.66 calls for a #4 AWG copper grounding electrode conductor. Question 63. Which of the following statements about “phase‑loss relays” is FALSE? A) They must be installed on each motor starter. B) They can be combined with overload protection. C) They provide a trip signal when any phase is missing. D) They are required by ASME A17.1 for traction elevators.
