Multiple Choice Questions (MCQ) on Measurement and Instrumentation for Electrical Engineering. All of these values are temperature dependent. Temperature. D : silver. This preview shows page 32 - 41 out of 57 pages. 22. Contributions through files (solved or unsolved MCQ files) are also welcomed . 34. Which of the following thermocouple has the lowest range of temperature a) type K b) type T c) type J d) type E 3. A thermocouple is a transducer. Advantages of Thermocouples : Temperature range: Most practical temperature ranges, from cryogenics to jet-engine exhaust, can be served using thermocouples. Object has varying emissivity. a) True. On the other side of the plate, six thermocouples are fitted to measure the temperature. The failure of power supply causes total loss of position data which cannot be retrieved even after restoration of … Difficulties Measuring with Thermocouples. (A) 523.2 K (B) -209.7 K (C) 709.7 K (D) -23.2 K . out of phase by 60°. Thermocouples are generally used for accurate temperature measurement upto 350°C; 550°C; 1400°C; 3500°C; Answer: C. 1400°C. (D) White (E) Black Ans: C 23. For the measurement of low resistances, Kelvin’s double bridge has high accuracy because: It has two set of ratio arms which eliminates effect of resistance of connecting lead It has a null indicating galvanometer Correct answer: (D) 45°. All a, b & c. However, for measuring higher temperature upto _____ °C, thermometer is made by filling nitrogen under pressure above the mercury, which stops the evaporation of mercury and reduces the … ohm Wheatstone ridge . A discussion of measurement procedures, the thermocouples used, their systematic errors and the correct ways to mount the thermocouples. Thermocouple Sensor. This white paper covers these topics in-depth for the most widely-used temperature transducers: thermocouples, resistance temperature detectors (RTDs), and thermistors. R Type. Temperature and Humidity Objective Questions. A thermocouple is defined as a thermal junction that functions based on the phenomenon of the thermoelectric effect, i.e. Also Read : Thermocouples Green Rot Effect 2. b. The wire leads are welded together to create a junction. (a) absolute (b) indicating (c) recording (d) … A thermocouple can measure a wide range of temperatures. The most rugged temperature sensing element listed here is a/an: (A) Thermocouple (B) Orifice plate (C) RTD (D) Filled bulb (E) Fire eye Ans: A An electronic controller creates a 4 to 20mA dc signal that must actuate a steam valve for temperature control. The electrical resistance of the substance. 0 – 50 mA range. 2. Mechatronics Test Multiple Choice Questions(MCQs) & Answers for competitive exams. 0 to 600 0 C: B. Hartke, Wikimedia Commons, public domain. Measuring Temperature. Ans: (b) PART 1: MCQs from Number 1 – 50 Answer key: PART 1. 9. They are also useful in cold-junction compensation circuits for wide temperature range thermocouples. The temperature range of ‘J’ type thermocouple … Jt is most widely used and common signal device for temperature measurement in industrial application. Multiple Choice Questions; The thermocouple is calibrated by measuring the thermal emf at various known temperatures, the reference junction being kept at 0° C. Peltier effect is exact opposite of Seebeck effect that the temperature difference is created by applying the voltage between two junctions of thermocouple circuit. Q12)Convert a temperature measurement of 250 deg C into Kelvin. This is helpful for the users who are preparing for their exams, interviews, or professionals who would like to brush up their fundamentals on the Sensors topic. The middle leg is Vout, where the temperature is read from. B. Platinum-rhodium. Thermocouples have become the industry-standard method for cost-effective measurement of a wide range of temperatures with reasonable accuracy. 6. When two wires of different metals are twisted together and heat applied to the junction, an e.m.f. Questions and Answers in Tests and Measurements. Set III Answer 34 Q No. For accurate temperature measurement in a thermocouple the _____ Options. (a) The resistance of the material used in the cell. How is temperature range calculated using a thermocouple sensor? If these properties change in a well-defined way, by measuring the property you can determine the temperature. Measuring lag is a dynamic characteristic. To determine actual temperature, the instrumentation must “adjust” for the difference between ambient temperature and 0°C. It is not easy to transform the voltage generated by a thermocouple into an accurate temperature reading for many reasons: the voltage signal is small, the temperature-voltage relationship is nonlinear, reference junction compensation is required, and thermocouples may pose grounding problems. Ability to measure high temperatures b. The accuracy of the thermocouples is 0.03°C. 2.5. +300 C to +1000C b. Thermocouples are generally used for accurate temperature measurement upto The temperature inside a furnace is generally measured by A Foreman of an automobile workshop wants to measure the temperature inside the piston of a car, whose temperature will be of the […] 3. 22333 msbte mcq question bank with answers pdf. d. Oxygen bomb Standard thermocouples get within approximately 1% of the actual temperature at the measuring junction, which is accurate enough for most applications. Typical thermocouple sensor. A : brass. A. This type of thermometer can measure a very small temperature change (0.0001°C) and there is a linear relationship between temperature and resistance over the range 0-100°C. The nonlinear relationship of sensor volts produced per degree temperature shift along the sensor wire pair is temperature range dependent, so tables or algorithms are used to produce accurate results for corresponding temperature range differences for each wire pair type. A resistance thermometer would be chosen because of: a. A cadmium sulphide cell is a. [A]. The seven basic types of temperature measurement sensors discussed here are thermocouples, resistive temperature devices (RTDs, thermistors), infrared radiators, bimetallic devices, liquid expansion devices, molecular change-of-state and silicon diodes. From formula (3), you can find the true open-circuit voltage that the thermocouple would produce with a reference junction at 0 °C, as shown in the following equation: VTCTTC() =VMEAS+VTCTref() (4) Electrical thermometer. Thermocouples are constructed from two wire leads made from different metals. Thermometer, thermocouple, sensor, tutor, vessel and water, multimeter and conducting rod. (c) The electrodes of the cell. This means that, if epoxy cement is used to attach the thermocouple, there must be no cement between the thermocouple and the pan. The thermocouple junction must be in direct contact with the pan or material being measured. To published, internationally specified tolerances as standard, typically ± 2.5°C for popular thermocouples, ±0.5°C for PRT. 121. Under these conditions, if the measurement temperature is above 0°ÊC, a thermocouple has a positive output; if below 0°ÊC, the output is negative. 1. 22333 msbte mcq question bank of Electronics measurement and instrumentation mcq. Chapter Flow Measurement consists of the following subtopics Bernoulli flowmeters, Ultrasonic Flowmeter, Magnetic flow meter, rotameter. This can become a problem when extreme high temperatures are being read. Jun 11,2021 - Measurements & Instruments - 3 MCQ | 20 Questions MCQ Test has questions of SSC preparation. Object and surrounding are at almost the same temperature. N Type. ... 1 Arrange the following components of temperature measurement system according to measurement system Hot body, Display system, Thermocouple, Amplifier and converter A Hot body----Display system-----Thermocouple-----Amplifier and converter. You have to select the right answer to the question. Show Answer Answer: C 10. A) Multiple Choice Questions (20 Marks) 1. To get the required thermocouple accuracy, follow the steps below: For example, a type K thermocouple is heated to 300 °C. PART 1: MCQs from Number 1 – 50 Answer key: PART 1. a) lead-wires b) self-heating c) uncertainty of bridge resistors d) all are source of errors 2. Accurate measurement of discharge can be made. C. Iron-constantan. Measurement and Instrumentation MCQs Answers Electrical Engineering Multiple Choice Questions Answers PDF Download. b) False. Sensors, transducers or any instrument do not respond immediately to the change in input. The more accurate compensation method uses two voltage-to-temperature conversion steps. Bimetallic thermometers use: A. How is temperature range calculated using a thermocouple sensor? Measuring lag refers delay in response of an instrument to the change in input. Thus, for known reference temperature and known thermocouple wire materials, output voltage Vo can be used to measure temperature. A number of thermocouples connected in series which increases sensitivity and accuracy by increasing the output voltage when measuring low temperature differences. The accuracy of a thermocouple depends on many factors including but not limited to electrical interference and the purity of the metals used. 1. 2. Q.43 Sensitivity of a thermocouple is 0.01V/°C. Measuring Instruments MCQ Question Answer. Thermocouple Types. Answer: a These properties include things such as: The volume (and density) of the substance. PART 2: MCQs from Number 51 – 100 Answer key: PART 2. For ungrounded Thermocouple (T/C), extension wire shield drain wire shall be grounded at receiver instrument end to the instrument circuit ground. 1. In dynamometer 3 … This test is Rated positive by 92% students preparing for SSC.This MCQ test is related to SSC syllabus, prepared by SSC teachers. Engineering :: Production Engineering. However, manufacturing improvements have also greatly improved the response times of thin-film PT100 probes. 136. 5. out of phase by 30°. Which of the following instruments will be used to measure the temperature above 1600 C. (a) A simple thermometer (b) Electrical resistance pyrometer. What does the internal resistance of a cell mean? Some are naturally more accurate than others because of the characteristics of the metals used. Depending on the metal wires used, a thermocouple is capable of measuring temperature … A junction of two dissimilar metal is called thermocouple.Thermocouple is a electrical sensor device used to measure temperature.Junction is a point from which temperature is measures. Which of the thermocouple can measure temperature in a comparatively high range. The fastest-possible temperature sensor is an exposed tip thermocouple. W. Quizzes MCQs. 4. Answer 1. Q 13)When the reference junction is the same temperature as the measurement junction in a thermocouple circuit, the output voltage (measured by the sensing instrument) is: (A) Zero (B) Reverse polarity (C) Noisy (E) Unreliable If these properties change in a well-defined way, by measuring the property you can determine the temperature. B Type. Furthermore, students can discuss the MCQs with other students. 1. For measuring temperature in the range of 200 to 30°C, following liquid is used in glass thermometer: (a) mercury (b) alcohol Class II c. Class III d. Class V. Answer: a. Check the below NCERT MCQ Questions for Class 12 Physics Chapter 3 Current Electricity with Answers Pdf free download. (A) Temperature (B) Flow (C) Density (D) All of the above Answer 2. The electrical resistance of the substance. what we offer ? The thermocouple voltage reading is then compensated to reflect the reference junction temperature. It is important that the reference junction be read as accurately as possible—with an accurate temperature sensor kept at the same temperature as the reference junction. K Type. A. Chromel-alumel. When a substance is heated, some of its physical properties can change. Thermocouples are generally used for accurate temperature measurement upto 350°C; 550°C; 1400°C; 3500°C; Answer: C. 1400°C. ... Pt/Pt-13% Rh thermocouple is used to measure the temperature in the range of: A. Which is the most suitable thermocouple transducer for the measurement of temperature in the range of 1,00 0 C to 1,500 0 C ? C : platinum. View Answer. This effect is used in a thermocouple to measure: a) e.m.f. hurdles of temperature measurement and simplifi ed the process for users, understanding the theories, operation, and inherent pitfalls of temperature measurements is still helpful. Iron constant on. Multiple Choice Question (MCQ) of Measurements page-13. This can be the definition of: a) Energy conservation b) Energy management c) Energy policy d) Energy Audit. With the minimum of error, a thermocouple signal from a cold junction which is at an unknown temperature. The judicious and effective use of energy to maximise profits and enhance competitive positions”. For surface temperature measurement one can use strain gauges; diaphragm; RTD; thermocouple; Answer: D. thermocouple. The air is heated by a heater which is connected to a fan. THEORY: Thermocouple is a transducer based on the seeback effect. 860°C b.835°C c. 900° d. 895°C Answer: d 17. Thermocouples are low cost, rugged and cover a wide temperature range it is estimated more than half of all temperature readings in USA industry are made using thermocouples. In the classical method of setting the cold-junction temperature the leads of the thermocouple sit in an ice bath, ensuring the reference temperature is 0°C. When the reference junction and the measurement junction are the same temperature, the net voltage is zero. The best and most economical choice would be to : a. the direct conversion of temperature differences to an electric voltage. 0 – 100 mA range. We have provided Current Electricity Class 12 Physics MCQs Questions with Answers to help students understand the concept very well. Answer/ Hint B. temperature is not equal to TR, Vo will be non-zero. a) True b) False c) None. Their main limitation is accuracy, in that systematic errors of less than one degree Celsius are difficult to achieve. For example, platinum and rhodium thermocouples are able to sense temperature within accuracies of 0.5°C. 7. -. In A.C. co-ordinate potentiometer, the currents in the phase and quadrature potentiometer are changed to be____. View answer. Which of the thermocouple one will choose to measure the temperature of 500°C? The nonlinear relationship of sensor volts produced per degree temperature shift along the sensor wire pair is temperature range dependent, so tables or algorithms are used to produce accurate results for corresponding temperature range differences for each wire pair type. 8. A close tolerance, 4-wire PRT will give best absolute accuracy and stability. 1. E Type. The drawbacks of incremental encoders are that. Measuring Temperature. An accurate measurement of the cold junction block acts as the reference temperature. Solution: Order thermocouples with special-limit wires, which can improve accuracy twofold. Thermocouple: Records temperature, Highly accurate, High range (-200 Celsius to 1500 Celsius), Used where in high temperatures, glass thermometers might not work or melt, We fix one of the two junctions of the thermocouple as the ice point and the other is variable. Answer: a. Clarification: Measuring lag is a dynamic characteristic. In order to prevent damage to the instrument, the selector switch of the ammeter should be first placed at. 23. What is the temperature measuring range of a digital thermometer in almost all kinds of environment? These measurements are used to monitor and control flow rates. Ans: a. In addition to accuracy based on the type of thermocouple, thermocouples have a specified range of temperatures over which they can operate.