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Preparation [MSEAE]
Question 1. Which of the following best describes a machine‑room‑less (MRL) elevator? A) An elevator that uses a separate gearless traction motor located in a dedicated machine room. B) An elevator that employs a hydraulic piston to move the car. C) An elevator whose drive and control equipment are installed in the hoistway, eliminating a separate machine room. D) An elevator that uses a counterweight made of concrete. Answer: C Explanation: MRL elevators house the traction motor, gear, and controller within the hoistway, removing the need for a separate machine room and saving building space. Question 2. In a traction elevator, the primary function of the governor is to A) Regulate the speed of the motor during normal operation. B) Detect over‑speed conditions and activate the safety gear. C) Maintain the balance between car and counterweight. D) Control the opening and closing of doors. Answer: B Explanation: The governor monitors car speed; if it exceeds a preset limit, it triggers the safety gear to clamp the hoist rope and stop the car. Question 3. The term “pit” in elevator terminology refers to A) The space at the top of the hoistway where the motor is installed. B) The recessed area at the bottom of the hoistway that houses the buffer and pit ladder. C) The shaft where the counterweight travels. D) The control panel location on the machine room floor. Answer: B
Preparation [MSEAE]
Explanation: The pit is the lower part of the hoistway, typically 1‑ 2 ft deep, containing the buffer, pit ladder, and sometimes the bottom of the car guide rails. Question 4. Which safety device provides instantaneous stopping of an elevator in case of a sudden over‑speed? A) Progressive safety gear. B) Instantaneous (or safety) gear. C) Door interlock switch. D) VVVF drive. Answer: B Explanation: The instantaneous safety gear engages immediately when the governor detects an over‑speed condition, clamping the rope to stop the car instantly. Question 5. In a hydraulic elevator, the purpose of the relief valve is to A) Increase the speed of the car on the up‑stroke. B) Prevent excessive pressure buildup in the hydraulic circuit. C) Control the door closing speed. D) Provide a backup power source. Answer: B Explanation: The relief valve opens when system pressure exceeds a preset limit, protecting components from over‑pressure damage. Question 6. Which of the following components is NOT typically part of an escalator’s handrail drive system? A) Drive sprocket. B) Chain tensioner. C) Handrail motor.
Preparation [MSEAE]
B) Counterweight. C) Door operator. D) Brake drum. Answer: A Explanation: Gearless traction elevators have a motor directly attached to the main sheave, eliminating gear reduction and improving efficiency. Question 10. The function of a “fishplate” in elevator guide rail assemblies is to A) Provide a decorative finish to the rail. B) Connect two rail sections end‑to‑end while maintaining alignment. C) Act as a load‑bearing support for the car. D) Serve as a sensor for car positioning. Answer: B Explanation: Fishplates are metal plates that bolt to the ends of guide rails, ensuring precise alignment and structural continuity. Question 11. Which sensor type is commonly used for floor‑level detection in modern elevators? A) Thermocouple. B) Proximity (inductive) sensor. C) Photo‑electric (optical) sensor. D) Hall‑effect magnetic sensor. Answer: D Explanation: Hall‑effect sensors detect the magnetic field from a target on the car, providing accurate floor‑level positioning.
Preparation [MSEAE]
Question 12. The primary advantage of a gear‑driven traction elevator over a gearless one is A) Higher energy efficiency. B) Lower initial cost for high‑rise applications. C) Faster travel speed. D) Ability to operate without a counterweight. Answer: B Explanation: Gear‑driven traction systems are less expensive for very tall buildings because the motor can be smaller, using gear reduction to achieve required torque. Question 13. In escalator terminology, the “step chain” is responsible for A) Driving the handrail. B) Moving the individual steps along the truss. C) Controlling the speed of the escalator. D) Synchronizing the lighting system. Answer: B Explanation: The step chain links the steps together and, when driven by the step sprocket, moves them up and down the escalator truss. Question 14. Which of the following is a required component of a lift’s emergency power system according to EN 81‑28? A) A diesel generator with at least 30 kW capacity. B) An uninterruptible power supply (UPS) capable of powering the car‑operating circuit for a minimum of 75 seconds. C) A solar panel array on the roof. D) A battery‑backed fire‑pump. Answer: B
Preparation [MSEAE]
D) The action of the safety gear. Answer: B Explanation: “Jacking” describes the hydraulic cylinder’s extension (up‑stroke) and retraction (down‑stroke) that moves the car. Question 18. What is the main purpose of the “door interlock” switch in an elevator? A) To prevent the car from moving when any door is not fully closed and locked. B) To control the speed of the door motor. C) To provide a signal for the lighting system. D) To enable emergency communication. Answer: A Explanation: The door interlock ensures that the elevator cannot be dispatched unless all doors are properly closed and locked, preventing accidents. Question 19. According to EN 115, the minimum required distance between the handrail and the step edge on a moving walkway is A) 150 mm. B) 200 mm. C) 250 mm. D) 300 mm. Answer: B Explanation: EN 115 specifies a minimum clearance of 200 mm to reduce the risk of entrapment between the handrail and moving step. Question 20. In an elevator’s control logic, a “relay ladder” is primarily used to A) Provide high‑speed data communication between floors.
Preparation [MSEAE]
B) Implement logical sequencing of inputs and outputs using electromechanical relays. C) Generate the variable frequency for the motor. D) Store error codes for diagnostics. Answer: B Explanation: Relay ladder diagrams represent the logical flow of contacts and coils in a relay‑based control circuit, dictating operation sequences. Question 21. Which of the following lubricants is most commonly recommended for elevator guide rail bushings? A) High‑temperature synthetic oil. B) Grease with a lithium complex base. C) Silicone spray. D) WD‑40. Answer: B Explanation: Lithium complex grease provides the necessary film thickness, temperature resistance, and water‑repellency for guide rail bushings. Question 22. The “load‑weighing device” (LWD) in a traction elevator is used to A) Measure the mass of the car plus passengers for overload protection. B) Determine the speed of the car. C) Control the door opening sequence. D) Provide power factor correction. Answer: A Explanation: The LWD senses the total load on the car and can inhibit operation if the load exceeds the rated capacity, protecting the system.
Preparation [MSEAE]
Explanation: ICC codes typically mandate a 60‑minute fire‑rating for hoistway enclosures in high‑rise structures to maintain structural integrity during a fire. Question 26. In a hydraulic elevator, the term “oil temperature sensor” serves to A) Adjust the speed of the car based on oil viscosity. B) Trigger an alarm if oil exceeds safe operating temperature. C) Measure the pressure in the hydraulic circuit. D) Control the door closing speed. Answer: B Explanation: Over‑temperature can degrade hydraulic oil; the sensor monitors temperature and initiates protective actions if limits are exceeded. Question 27. Which of the following is NOT a typical function of an elevator’s “controller board”? A) Processing user inputs from floor buttons. B) Generating variable‑frequency drive signals. C) Directly supplying power to the traction motor. D) Monitoring safety circuit status. Answer: C Explanation: The controller board handles logic and communication; power to the motor is supplied by the drive and power electronics, not directly from the controller. Question 28. The “comb‑plate impact switch” on an escalator is designed to A) Detect when a passenger’s shoe contacts the comb plate, stopping the escalator. B) Measure the speed of the handrail. C) Provide a backup power source for the step chain.
Preparation [MSEAE]
D) Signal the need for lubrication. Answer: A Explanation: The comb‑plate impact switch activates when a foreign object (e.g., a shoe) contacts the comb plate, immediately stopping the escalator to prevent injury. Question 29. According to EN 81‑20/50, the minimum headroom clearance above the car top landing must be A) 1.5 m. B) 2.0 m. C) 2.2 m. D) 2.4 m. Answer: C Explanation: EN 81‑20/50 specifies a minimum clear headroom of 2.2 m above the car top landing to ensure passenger safety. Question 30. In an elevator’s VVVF drive, the “vector control” method primarily improves A) Energy efficiency at low speeds. B) The quality of voice communication. C) The speed of the door operator. D) The reliability of the safety gear. Answer: A Explanation: Vector control (field‑oriented control) allows precise torque and speed regulation, especially beneficial for low‑speed operation, reducing energy consumption. Question 31. The “pit ladder” is required in elevator installations to A) Provide a means for maintenance personnel to access the buffer and pit components safely.
Preparation [MSEAE]
Question 34. Which of the following is a primary advantage of a “gearless traction” system over a “hydraulic” system for mid‑rise buildings? A) Lower initial installation cost. B) Higher energy efficiency and smoother ride quality. C) Ability to operate without a counterweight. D) Simpler maintenance due to fewer moving parts. Answer: B Explanation: Gearless traction elevators are more energy‑efficient and provide a smoother ride, making them preferable for mid‑rise applications despite higher upfront cost. Question 35. The “over‑travel sensor” in an elevator is used to A) Detect when the car exceeds its top or bottom travel limits and stop the motor. B) Measure the speed of the car during normal operation. C) Control the illumination of the car interior. D) Activate the fire‑service mode. Answer: A Explanation: Over‑travel sensors monitor the car’s position beyond its normal range and command the controller to stop the motor to prevent damage. Question 36. In a modern elevator, the “door‑status feedback” is typically transmitted to the controller via A) Analog voltage levels. B) Digital serial communication (e.g., CAN bus). C) Mechanical linkages. D) Pneumatic pressure signals. Answer: B
Preparation [MSEAE]
Explanation: Digital communication protocols like CAN bus convey door‑status information quickly and reliably to the controller. Question 37. Which of the following is a required safety feature for escalators installed in public buildings according to EN 115? A) A handrail speed limit of 0.5 m/s. B) An emergency stop button located at every landing. C) A transparent step surface. D) A built‑in fire‑suppression system. Answer: B Explanation: EN 115 mandates that emergency stop devices be provided at each landing to allow immediate shutdown in case of an incident. Question 38. The term “rope termination” refers to A) The point where the hoist rope is attached to the car frame. B) The method of securing the rope ends to the sheave or drum, usually by a swaged or spliced fitting. C) The process of cutting excess rope length. D) The sensor that monitors rope tension. Answer: B Explanation: Rope termination is the technique (e.g., swage, splice, or mechanical fitting) used to secure rope ends to the sheave or drum, ensuring load transfer. Question 39. In the context of elevator maintenance, “PM” stands for A) Power Management. B) Preventive Maintenance. C) Performance Monitoring.
Preparation [MSEAE]
B) The temperature of the step chain. C) The voltage supplied to the handrail motor. D) The ambient humidity in the escalator shaft. Answer: A Explanation: The step‑speed sensor monitors the sprocket’s rotation, providing feedback to maintain the desired step speed and ensure synchronization. Question 43. According to ASME A17.1, which of the following is the minimum required fire‑resistance rating for a machine‑room in a new construction? A) 30 minutes. B) 60 minutes. C) 90 minutes. D) 120 minutes. Answer: B Explanation: ASME A17.1 typically requires a 60‑minute fire‑rated enclosure for machine rooms to protect critical equipment during a fire. Question 44. The “handrail drive motor” on an escalator is synchronized with the step drive motor by means of A) A mechanical gear train. B) An electronic speed controller that uses feedback from a tachometer. C) A pneumatic coupling. D) A hydraulic pump. Answer: B Explanation: Electronic speed controllers receive tachometer feedback from both motors to keep handrail speed matched to step speed, preventing drift.
Preparation [MSEAE]
Question 45. In a hydraulic elevator, the “pump‑motor” is typically A) Direct‑coupled to the hydraulic pump for efficient power transmission. B) Mounted on the car roof. C) Powered by a DC battery. D) Used only for emergency operation. Answer: A Explanation: The pump‑motor is usually a direct‑drive unit, where the electric motor is coupled directly to the hydraulic pump, providing reliable fluid flow. Question 46. Which of the following is a primary function of the “travel‑limit switch” in an elevator? A) To limit the maximum speed of the car. B) To define the top and bottom positions where the car must stop. C) To control the lighting inside the car. D) To monitor the temperature of the motor winding. Answer: B Explanation: Travel‑limit switches detect when the car reaches its designated top or bottom floor and signal the controller to stop the motor. Question 47. The “step‑belt” in a moving walkway differs from an escalator step chain because A) It operates at a higher speed. B) It carries a continuous belt rather than individual steps. C) It is made of plastic instead of steel. D) It requires no lubrication. Answer: B
Preparation [MSEAE]
D) Activating the fire‑service mode automatically. Answer: B Explanation: EN 81‑71 specifies that rescue devices must allow safe evacuation of occupants without reliance on external power for at least 30 minutes. Question 51. In a traction elevator, the “sheave” is the component that A) Supports the car’s guide shoes. B) Guides the hoist rope and changes its direction to lift the car. C) Houses the safety gear. D) Controls the door operation. Answer: B Explanation: The sheave (or drum) is the large pulley around which the hoist rope is wound; its rotation lifts or lowers the car. Question 52. Which of the following statements about “machine‑room‑less” (MRL) elevators is FALSE? A) They require a separate dedicated machine room. B) They often use a gearless traction motor. C) They can be installed in buildings with limited overhead space. D) Their drive components are mounted in the hoistway. Answer: A Explanation: MRL elevators eliminate the need for a separate machine room; the false statement is that they require one. Question 53. The “hydraulic accumulator” in a hydraulic elevator system is used to A) Store pressurized oil to smooth out pressure fluctuations and assist in car lowering.
Preparation [MSEAE]
B) Convert hydraulic energy into electrical power. C) Filter contaminants from the oil. D) Provide a backup power source for the pump. Answer: A Explanation: The accumulator (often a gas‑charged bladder) stores energy, helping maintain steady pressure and providing a smoother ride. Question 54. In escalator safety, the “skirt‑deflection sensor” is designed to A) Detect the presence of a foreign object caught in the step skirt and stop the escalator. B) Measure the speed of the moving handrail. C) Control the illumination of the escalator steps. D) Monitor the temperature of the step chain. Answer: A Explanation: Skirt‑deflection sensors sense abnormal movement of the step skirts, indicating a potential entrapment, and trigger an emergency stop. Question 55. Which of the following is NOT a typical feature of a “micro‑processor‑based” elevator controller? A) Real‑time monitoring of all safety circuits. B) Ability to store and display diagnostic fault codes. C) Direct mechanical linkage to the door operator. D) Programmable logic for custom service modes. Answer: C Explanation: Modern controllers use electronic interfaces, not direct mechanical linkages, to control doors and other functions.
