Limit Switch Question & Answers May 11, 2023 By Wat Electrical This article lists 30 Limit Switch MCQs for engineering students. All the Limit Switch Questions & Answers below include a hint and a link to the relevant topic wherever possible. This is helpful for users who are preparing for their exams, interviews, or professionals who would like to brush up on the fundamentals of Limit Switch. or the position of a machine component. It consists of a movable lever or actuator that makes contact with a stationary electrical contact when a certain physical limit is reached. Limit switches are commonly used in industrial and manufacturing settings to monitor the movement of machines and equipment. For example, a limit switch might be used to detect when a conveyor belt has reached the end of its travel or when a robotic arm has reached a certain position. Limit switches can be either normally open (NO) or normally closed (NC). In a NO switch, the circuit is open when the actuator is not in contact with the stationary contact. In a NC switch, the circuit is closed when the actuator is not in contact with the stationary contact. Limit switches can be operated mechanically or electronically, and they are often used in combination with other types of digital and analog sensors and control systems to provide precise and reliable machine control. 1). What is the main purpose of a limit switch? To control the speed of a motor To detect the presence or absence of an object or limit of its motion To measure the temperature of a process D) None of the above Hint 2). Which of the following is NOT a type of limit switch? Roller lever switch Mercury switch Plunger switch All of the above Hint 3). How does a limit switch typically send a signal to a control system? By using a pneumatic or hydraulic connection By sending an electrical signal through a wire By using a mechanical linkage Both a and c Hint 4). What is the difference between a normally open (NO) and normally closed (NC) limit switch? The position of the switch actuator The voltage rating of the switch The direction of the signal sent to the control system All of the above Hint 5). Which of the following is a common application for a limit switch? Measuring the weight of a product Controlling the temperature of a process Stopping a conveyor belt when an object reaches the end of the line Both a and b Hint 6). Who is credited with inventing the first limit switch? Nikola Tesla Thomas Edison Henry Ford Michael Hint 7). In what year was the first limit switch invented? 1870 1905 1920 2000 Hint 8). What was the first application of limit switches? Controlling the movement of elevators Detecting the position of steam valves in power plants Stopping conveyor belts in factories All of the above Hint 9). When were roller lever limit switches first introduced? 1920s 1940s 1960s 1980s Hint 10). What is the most recent innovation in limit switch technology? Wireless communication Fiber optic sensing Nanotechnology Both b and c Hint Limit Switch MCQ for Quiz 11). Which of the following is NOT a common type of limit switch actuator? Roller lever Plunger Float Mercury Hint 12). What is a magnetic reed switch? A type of limit switch that uses a magnet and a reed switch to detect motion or position A type of limit switch that uses a spring-loaded plunger to detect pressure A type of limit switch that uses a float to detect liquid level None of the above Hint 13). Which of the following is NOT a type of roller lever switch? Spring return Top push Side push Floating plunger Hint 14). What is a proximity switch? A type of limit switch that detects the presence of a metal object without physical contact A type of limit switch that uses a camera to detect motion or position A type of limit switch that uses a laser to detect the position of an object Both b and c Hint 15). What is a micro switch? A type of limit switch that is very small in size A type of limit switch that uses microprocessors to detect motion or position A type of limit switch that uses microscopic sensors to detect changes in temperature or pressure A type of limit switch that uses a laser to detect the position of an object Hint 16). What is a common cause of a limit switch failing to actuate? The actuator is worn or damaged The wiring is loose or disconnected The switch contacts are dirty or corroded None of the above Hint 17). What can cause a limit switch to chatter or bounce? Loose wiring A worn or damaged actuator Dirty or corroded contacts All of the above Hint 18). How can you test a limit switch to determine if it is functioning properly? Use a multimeter to measure continuity across the switch contacts Observe the motion or position of the actuator and check if the switch actuates Check the wiring for continuity and proper connections Both b and c Hint Read more about Multimeter 19). What is a common cause of limit switch contacts welding together? Excessive electrical load High temperatures Excessive mechanical stress on the actuator Both a and c Hint 20). What can cause a limit switch to fail prematurely? Exposure to harsh environmental conditions Incorrect installation or wiring Excessive vibration or shock All of the above Hint Limit Switch MCQ for Exams 21). What is the maximum voltage rating of a typical limit switch? 12 volts 24 volts 120 volts 240 volts Hint 22). What is the typical current rating of a limit switch? 11 ampere 50 amperes 10 amperes 20 amperes Hint 23). What is the typical temperature rating of a limit switch? -20°C to +50°C -40°C to +70°C -60°C to +120°C -80°C to +150°C Hint 24). What is the typical life expectancy of a limit switch? 10,000 cycles b) 100,000 cycles 500,000 cycles 1,000,000 cycles Hint 25). What is the typical response time of a limit switch? 1 millisecond 10 milliseconds 100 milliseconds 1 second Hint 26). Which type of limit switch is best suited for applications where precise position sensing is required? Basic Safety Precision All of the above Hint 27). What is the function of the actuator in a limit switch? To provide electrical contacts To protect the switch from environmental damage To trigger the switch based on motion or position All of the above Hint 28). Which type of actuator is best suited for applications where the switch must be triggered from an angle? Plunger Roller lever Rotary lever Wobble stick Hint 29). Which of the following factors can cause a limit switch to fail prematurely? Mechanical wear and tear Electrical overload Contamination All of the above Hint 30). A limit switch with a normally open (NO) contact configuration will be in what state when it is not actuated? Open Closed Short-circuited None of the above Hint Time's up