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Induction Motor Interview Questions with Answers | Part-1

Induction Motor Interview Questions with Answers | Part-1

Induction Motor Interview Questions with Answers | Part-1 Induction Motor Interview Questions with Answers | Part-1 Q.1 The frame of an induction motor is made of (A) aluminium (B) silicon steel (C) closed grained cast iron (D) stainless steel (E) bronze Answer:  (C) closed grained cast iron Q.2 The stator frame is an induction motor is used to (A) hold the armature stampings in position (B) ventilate the armature (C) protect the whole machine (D) provide return path for flux Answer:  (A) hold the armature stampings in position Q.3 The stator core of a 3 phase induction motor is laminate in order to reduce the (A) eddy current loss (B) hysteresis loss (C) both hysteresis and eddy current loss (D) weight of the stator (E) windage and friction losses Answer: (A) eddy current loss Q.4 An induction motor works with (A) dc only (B) ac only (C) ac and dc both (D) none of these Answer:  (B) ac only Q.5 Which of the following statement associated with polyphase induction motor is/are correct?

Economic Choice Of Conductor in Transmission Line Design

Economic Choice Of Conductor in Transmission Line Design Economic Choice Of Conductor in Transmission Line Design Conductors used should have following electrical and physical properties: Chosen conductor must have high conductivity. In must have large tensile strength. It must have large corrosion resistance characteristics. It needs to have large melting point and good thermal stability. It has good ductile property. Following conductor material are most commonly use for transmission line : Hard drown copper Aluminium Aluminium conductors steel reinforced  (ACSR) In india, ACSR Conductors are more commonly used. From 1990 onwards, America, Australia and few european countries starts using All aluminium alloy conductor (AAAC). AAAC consists of aluminium, boron, silicates etc. As a main component material. Size of the conductor chosen depends on following factors : Length of the transmission line Voltage drop Load demand Voltage level Allowable temperature limit Current carrying capaci

Selection of voltage for high voltage transmission lines

Selection of voltage for high voltage transmission lines As power plants are located for away from the load centers so it is necessary transmit power at high voltages. Selection of voltage for high voltage Transmission Line Selection of voltage level depends on the following factors: Conductor size Future load growth Grid inter connection Cost of the transmission line Cost of equipment e.g. transformers insulators insulators, circuit breakers etc. Transmission line length Voltage regulation Power loss Intial and operating cost There is a exponential increase in the cost for voltage level above 220 kV and above. Voltages in India are: For short transmission line - 11kV, 22kV and 33 kV For medium transmission line - 66kV For long transmission line - 110kV, 220kV, and 440kV Future load growth depends on the possible development in that region. The choice of voltage level also depends on the conductor size. Conductor size affects the performance of transmission line in the form of transmis

What is Contingency Analysis? | Necessity of contingency analysis

What is Contingency Analysis? | Necessity of contingency analysis What is Contingency Analysis? | Necessity of contingency analysis Contingency Analysis(CA)is one of the "security analysis" applications in a power utility control centre. Its purpose is to analyze the power system in order to identify the overloads. Contingency analysis is abnormal condition in electrical network.It put whole system or a  part of the system under stress. It occurs due to sudden opening of a transmission line. Generator  tripping. Sudden change in generation. Sudden change in load value. Contingency analysis provides tools for managing, creating, analyzing, and reporting lists of contingencies and associated violations. CA is used as a study tool for the off-line analysis of contingency events, and as an online tool to show operators what would be the effects of future outages. Security is determined by the ability of the system to withstand equipment failure. Weak elements are those that prese

What is Substation? And Function Of Substation

What is Substation? It is a system utilized to change and to improve the characteristics of the supply system as per load requirements. What is Substation? And Function Of Substation Between the generating station and consumer, electric power may pass through various substations having different voltage levels.  Substations may be owned and operated by an  electrical utility, or may be owned by a large industrial or commercial customer. Functions of a sub-station An electricity supply undertaking generally aims at the following: Supply of required electrical power to all the consumers continuously at all times. Maximum possible coverage of the supply network over the given geographical area. Maximum security of supply. Shortest possible fault duration. Optimum efficiency of plants and the network. Supply of electrical power within targeted frequency limits. Supply of electrical power within specified voltage limits. Supply of electrical energy to the consumers at the lowest cost. As a

Electrical Engineering Jobs 2023

Electrical Engineering Jobs 2023 Electrical Engineering Jobs Hello Electrical Engineers, Now Don't to worry about job. For Daily Update for job and Daily useful Electrical theories follow by email our website. By Following our website, we provide daily updated jobs notification and also provide useful content related to interview and competitive exam via email. So, Now Don't to worry about for your career. Submit Your Resume Now 👇👇👇 Useful Electrical Articles 👇👇 Future of Electric Cars Objectives of Electrical Safety Terms Related to Electrical Safety Electrical Accidents | How can be Avoid Electrical Accident? What is Microprocessor? | Block Diagram of Microprocessor | Application of Microprocessor What is Computer? | Characteristics of Computer | Limitations of computer | Types of Computer Advantages and Disadvantages of Electromagnetic Relay Over Current Protection Of Transformer

Requirements Of Transmission Line

Requirements Of Transmission Line Requirements Of Transmission Line All the Requirements of transmission line is mentioned below: Requirements Of Transmission Line: ✓Transmission lines should transfer power for particular distance economically. ✓ Transmission of power should be done for a given power factor. ✓Transmission of power should be done within desired limit of voltage regulation, efficiency and losses. ✓Transmission should withstand wind pressure and temperature variations. May You Like to Read: Types of Electric Drives Future of Electric Cars Objectives of Electrical Safety Terms Related to Electrical Safety ✓ In a transmission line formation of corona and respective loss should be less. ✓Requirement of charging current for a transmission line for transfer of power should be less. ✓Transmission lines should be mechanically strong, so supply of power should not be affected due to mechanical

Surge Impedance Loading or SIL - Definition, Formula

Surge Impedance Loading or SIL - Definition, Formula Surge Impedance Loading or SIL - Definition, Formula What is Surge Impedance Loading? Surge Impedance Loading or SIL is the power demand or load supplied by the transmission line having no resistance by considering unity load power factor. Explanation of Surge Impedance Loading or SIL In case of transmission line surge Impedance Loading is depends on inductance and capacitance of the transmission line. Formula of Surge Impedance Loading or SIL Formula of Surge Impedance Loading or SIL Where, L - Inductance of transmission Line             C - Capacitance of transmission Line   Surge Impedance Loading is independent of the transmission line length.  In this case I^2 X of the transmission line provides charging kVA of the transmission line. SIL or Surge Impedance Loading can also be given as below formula: Formula of Surge Impedance Loading or SIL Formula of Surge Impedance Loadin

Selection and Specifications Of Transmission Line

Selection and Specifications Of Transmission Line Selection and Specifications Of Transmission Line Following factors are affecting the selection and specifications of transmission lines: ✓ Size of transmission conductors ✓ Spacing and distance between conductors ✓ Insulator types ✓ Insulation co-ordination ✓ Voltage regulation ✓ Power losses ✓ Voltage level of transmission line ✓ Tower designs ✓ Clearance levels ✓ Noise emission ✓ Corona loss ✓ Weather conditions e.g. temperature, wind etc. ✓ Mechanical strength of selected conductors ✓ Air pollution In high temperature regions, conductor material chosen for transmission line should  have higher temperature coefficient of resistance. Wind load affects the sag clearance putting more pressure on transmission lines. Mechanical strength of selected conductors should be higher to avoid breaking of conductor due  to wind pressure or increase in temperature etc. Moisturised air or polluted air causes chemical

Electrical Safety Signs and Symbols

Electrical Safety Signs and Symbols Electrical Safety Signs and Symbols The safe working procedure includes Safety precautions during the execution of work and shall the site shall be kept safe even after working hours are over. All safety gears should be wore by the working persons and the equipment must be handled in correct way. The instructions in simple form play a crucial role in such cases. But the time required to go through text material is more. During emergency, the time required to react is very less so safety sign play a very important role. You may Also Read: Objectives of Electrical Safety Terms Related to Electrical Safety Requirements of Safety Signs The requirement of safety signs are as below: >> It should be illustrative i.e.the person must understand its meaning easily. >> It should convey the instruction easily. >> It should be Pictographically so that it is easily understood by all persons.