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Question 1. What is the function of a contactor in an elevator control circuit? A) To provide overload protection B) To open and close power circuits to the motor C) To regulate voltage levels D) To convert AC to DC Answer: B Explanation: A contactor is an electrically controlled switch used for switching a power circuit, such as turning the elevator motor on or off. Question 2. According to Ohm’s Law, what is the current flowing through a 10-ohm resistor connected to a 120V supply? A) 1.2 A B) 12 A C) 0.12 A D) 1200 A Answer: B Explanation: Ohm’s Law states I = V/R, so current I = 120V / 10Ω = 12A. Question 3. What type of motor is most commonly used in traction elevator systems? A) Synchronous motor B) Stepper motor C) Induction motor D) Universal motor Answer: C Explanation: Induction motors are preferred in elevator traction systems for their reliability and efficiency. Question 4. What is the main purpose of a governor in an elevator system? A) To control door operation B) To detect overspeed and activate safety devices
C) To provide lighting in the car D) To regulate hydraulic pressure Answer: B Explanation: The governor detects if the elevator exceeds safe speeds and triggers the safety mechanism. Question 5. In a parallel circuit, how does the total resistance compare to the smallest resistor in the circuit? A) It is equal to the smallest resistor B) It is greater than the largest resistor C) It is less than the smallest resistor D) It is the sum of all resistors Answer: C Explanation: In parallel circuits, total resistance is always less than the smallest individual resistor. Question 6. What is the primary function of the overspeed device in an elevator? A) To stop the elevator at each floor B) To slow the elevator during normal travel C) To activate safety mechanisms if the elevator moves too fast D) To control door opening speed Answer: C Explanation: The overspeed device detects excessive speed and triggers safety stops. Question 7. Which code sets the standard for elevator and escalator safety in the United States? A) NEC B) ASME A17. C) OSHA 1910 D) NFPA 70E Answer: B
B) 18 inches C) 24 inches D) 43 inches Answer: D Explanation: ASME A17.1 requires a minimum 43-inch clearance for safety and maintenance. Question 12. What is the effect of connecting batteries in series? A) Voltage increases, current stays the same B) Voltage stays the same, current increases C) Both voltage and current increase D) Both voltage and current decrease Answer: A Explanation: Series connection adds the voltages of each battery while current capacity remains unchanged. Question 13. Which device is used to ensure the elevator doors do not open unless the car is at a landing? A) Governor B) Door interlock C) Terminal switch D) Brake Answer: B Explanation: Door interlocks prevent doors from opening unless the car is safely positioned at a landing. Question 14. How frequently must Category 1 tests be performed according to ASME A17.1? A) Monthly B) Quarterly C) Annually D) Every five years
Answer: C Explanation: Category 1 tests, which include safety and buffer tests, are required annually. Question 15. What does a ladder logic diagram represent in elevator control systems? A) Mechanical linkage B) Power distribution C) Sequential control logic D) Hydraulic pressure Answer: C Explanation: Ladder logic diagrams depict the sequence of electrical control operations. Question 16. In a geared traction elevator, what is the function of the gear? A) To increase motor speed B) To reduce motor speed and increase torque C) To control door movement D) To regulate voltage Answer: B Explanation: The gear reduces speed and increases torque to move the elevator car efficiently. Question 17. Which of the following best describes the main advantage of a gearless traction elevator? A) Lower installation cost B) Higher efficiency and smoother operation C) Simpler maintenance D) Lower power consumption Answer: B Explanation: Gearless traction elevators offer smooth, efficient, and high-speed operation. Question 18. What is the purpose of an elevator pit ladder? A) To support the car
Question 22. What is the main function of a hoistway limit switch? A) To regulate lighting B) To cut power if the car travels beyond its limits C) To control door opening speed D) To measure car speed Answer: B Explanation: Hoistway limit switches prevent the elevator from exceeding its safe travel range. Question 23. Which type of fire service operation returns the elevator to a designated floor and removes it from normal service? A) Phase II B) Phase I C) Recall override D) Emergency power Answer: B Explanation: Phase I fire service recalls the elevator to a safe floor and disables normal calls. Question 24. In a three-phase AC motor, how are the windings typically connected? A) Series only B) Parallel only C) Star (wye) or delta D) Open circuit Answer: C Explanation: Three-phase motors are connected in star (wye) or delta configurations. Question 25. What is the role of a compensation rope in a high-rise elevator? A) To balance the weight of the car and counterweight B) To prevent overspeed
C) To provide emergency braking D) To open doors Answer: A Explanation: Compensation ropes balance the weight difference as the car moves, improving performance. Question 26. Which maintenance task is essential for elevator traction sheaves? A) Lubricating the grooves B) Cleaning with water C) Painting D) Polishing with abrasives Answer: A Explanation: Lubrication reduces wear and prolongs sheave life. Question 27. What is the function of a main line disconnect in an elevator electrical system? A) To increase voltage B) To provide a means to safely disconnect power C) To measure current D) To control car speed Answer: B Explanation: The main line disconnect allows safe disconnection of the elevator from power. Question 28. What does a “buffer” do at the bottom of an elevator shaft? A) Smoothly slows the car if it overruns the lowest landing B) Increases car speed C) Opens the doors D) Balances the counterweight Answer: A Explanation: Buffers absorb impact and slow the car in case of overrun.
C) 2,500 lbs D) 5,500 lbs Answer: A Explanation: The motor lifts the difference between car and counterweight—500 lbs. Question 33. What is the main cause of hydraulic elevator oil leaks? A) Worn seals B) Faulty relays C) Broken step chains D) Overheated motors Answer: A Explanation: Oil leaks are most often caused by deteriorated or worn seals. Question 34. Which type of schematic is most commonly used to troubleshoot elevator control systems? A) Block diagram B) Ladder diagram C) Pictorial diagram D) Hydraulic diagram Answer: B Explanation: Ladder diagrams are used for troubleshooting control circuits. Question 35. What type of sensor is commonly used in elevator door safety edges? A) Proximity sensor B) Pressure sensor C) Optical (light curtain) sensor D) Temperature sensor Answer: C Explanation: Optical sensors (light curtains) detect obstructions in the door opening.
Question 36. What is the primary purpose of routine elevator maintenance? A) To increase car speed B) To ensure safety and reliable operation C) To decrease downtime D) To reduce cable length Answer: B Explanation: Regular maintenance ensures safety and reliability. Question 37. What is the function of a phase reversal relay in an elevator system? A) To prevent incorrect motor rotation due to reversed phases B) To reduce voltage C) To open the doors D) To increase current Answer: A Explanation: Phase reversal relays prevent motor damage caused by incorrect phase sequence. Question 38. In an AC circuit, what does “power factor” refer to? A) The ratio of resistance to inductance B) The ratio of real power to apparent power C) The total voltage D) The total current Answer: B Explanation: Power factor equals real power divided by apparent power. Question 39. What is a key function of terminal slow-down switches in elevator systems? A) To stop the car at mid-level floors B) To slow the car before reaching the terminal landings C) To activate fire recall D) To control lights
B) To drive the handrail C) To support the truss D) To open the comb plate Answer: B Explanation: The drive wheel powers the handrail, keeping its movement synchronized with the steps. Question 44. What does “bonding” accomplish in elevator electrical systems? A) Reduces voltage B) Ensures all metal components are at the same electrical potential C) Increases current flow D) Enhances insulation Answer: B Explanation: Bonding prevents electrical shock by equalizing potential on all metal parts. Question 45. What is the maximum gap allowed between an escalator step and the skirt panel according to ASME A17.1? A) 1/16 inch B) 1/8 inch C) 1/4 inch D) 1 inch Answer: B Explanation: ASME A17.1 stipulates a maximum 1/8-inch gap for passenger safety. Question 46. What is the main function of elevator car guides? A) To support the counterweight B) To keep the car aligned in the hoistway C) To control car speed D) To open the doors Answer: B
Explanation: Car guides ensure smooth and accurate vertical movement. Question 47. What happens if a relay coil in an elevator controller burns out? A) The circuit remains closed B) The relay contacts open, breaking the circuit C) The elevator speeds up D) The elevator overheats Answer: B Explanation: A failed relay coil causes the contacts to open, interrupting the circuit. Question 48. What device measures electrical current? A) Ohmmeter B) Voltmeter C) Ammeter D) Wattmeter Answer: C Explanation: An ammeter is used to measure current in a circuit. Question 49. Which type of drive is most commonly used in modern escalators? A) Hydraulic B) Gearless AC motor C) Geared AC motor D) Pneumatic Answer: C Explanation: Geared AC motors are standard in escalator drive systems. Question 50. What is the primary cause of escalator chain elongation? A) Overheating B) Lubrication failure
Question 54. What is the primary risk of not grounding elevator electrical equipment? A) Increased efficiency B) Overheating C) Electric shock hazard D) Faster operation Answer: C Explanation: Ungrounded equipment poses a serious shock risk to personnel. Question 55. What is a key inspection item for elevator governor ropes? A) Oil level B) Rope diameter and condition C) Brake pad wear D) Door alignment Answer: B Explanation: Rope diameter and wear are critical for safe governor operation. Question 56. What is the main function of an elevator’s counterweight? A) To reduce the load on the motor B) To slow the car C) To open the doors D) To increase ride speed Answer: A Explanation: Counterweights balance the car, reducing the force required from the motor. Question 57. What is the function of a control valve in a hydraulic elevator? A) To open the doors B) To regulate oil flow to the piston C) To power the hoist motor
D) To control car speed Answer: B Explanation: The control valve manages the hydraulic oil flow, controlling car movement. Question 58. According to ASME A17.1, what is the minimum required illumination in an elevator machine room? A) 5 foot-candles B) 10 foot-candles C) 19 foot-candles D) 50 foot-candles Answer: C Explanation: ASME A17.1 requires at least 19 foot-candles in the machine room for safe work. Question 59. What is the most common cause of electrical arcing in elevator controllers? A) Dirty contacts B) Over-tightened screws C) Poor lubrication D) Excessive humidity Answer: A Explanation: Dirty or worn contacts can cause arcing, leading to component failure. Question 60. What is the purpose of “buffer switches” at the bottom of an elevator hoistway? A) To alert the controller of buffer engagement B) To power the lights C) To slow the car at mid-level D) To open the doors Answer: A Explanation: Buffer switches inform the controller when the car contacts the buffer.
Answer: B Explanation: Sheaves are grooved wheels that guide elevator ropes. Question 65. What should be done before entering an elevator pit for inspection? A) Check oil level B) Perform lockout/tagout and test for absence of voltage C) Lubricate the buffer D) Measure car speed Answer: B Explanation: Always de-energize equipment and verify absence of voltage before entry. Question 66. What is the typical use of a “terminal stopping switch” in an elevator? A) To stop the elevator at the terminal landing B) To open the doors at each floor C) To power the lights D) To slow the car at mid-level Answer: A Explanation: Terminal stopping switches halt the car at the top or bottom landing. Question 67. What is the function of a main line fuse in an elevator controller? A) To amplify current B) To protect the circuit from overcurrent C) To open the doors D) To slow the car Answer: B Explanation: Fuses prevent damage by disconnecting the circuit if current is excessive. Question 68. What does a “car top inspection station” allow? A) Programming of control logic
B) Safe, slow movement of the elevator for inspection C) Increasing car speed D) Testing of fire recall Answer: B Explanation: The car top inspection station provides controls for safe, slow movement during servicing. Question 69. What is the function of an elevator hall call button? A) To stop the car B) To signal for an elevator at a landing C) To open the doors manually D) To reset the controller Answer: B Explanation: Hall call buttons request elevator service at a specific landing. Question 70. What is the most common type of braking system used in traction elevators? A) Drum brake B) Disc brake C) Electromagnetic spring-applied brake D) Air brake Answer: C Explanation: Electromagnetic brakes are standard for their reliability and fail-safe operation. Question 71. What is the function of a door open relay in elevator controls? A) To open the main line disconnect B) To command the doors to open C) To slow the elevator D) To recall the car Answer: B Explanation: The door open relay activates the door operator to open the doors.
