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Directional relays are based on flow of power.

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Description : In the induction type directional over current relay, when a short-circuit occurs in the circuit (A) power flows in reverse direction (B) power flows in normal direction (C) directional power element does not operate (D) over current element is not energized

Answer : In the induction type directional over current relay, when a short-circuit occurs in the circuit power flows in reverse direction

Answer : Impedance relays are used for phase faults on long line.

Description : IDMT relays are used to protect the transformer against :  (A) Internal short -circuits (B) Open circuits (C) External short circuits (D) Oil leakage

Answer : IDMT relays are used to protect the transformer against : External short circuits

Answer : The inverse definite mean time relays are used for over current and earth fault protection of transformer against internal short-circuits.

Answer : The single phasing relays are used for the protection of three phase motors.

Answer : Discrimination between main and back up protection is provided by the use of relays which are slow.

Answer : To protect most of the electrical equipment handling low power, the types of relays used are thermocouple, electronic and bimetallic.

Answer : Protective relays are devices that detect abnormal conditions in electrical circuits by measuring constantly the electrical quantities which differ during normal and abnormal conditions.

Description : D.C. shunt relays are made of?

Answer : D.C. shunt relays are made of many turns of thin wire.

Answer : Thermal overload relays are used to protect the motor against overcurrent due to heavy loads.

Answer : Overload relays are of induction, solid state, thermal, electromagnetic type.

Answer : Relays can be designed to respond to changes in resistance, reactance or impedance voltage and current, light intensity, temperature.

Description : How many types of types of relays are there?

Description : Consider the following statements. Which of these statements are correct ?  (1) Reactance relays are preferred for ground fault relaying  (2) Impedance relays are most suitable for:protecting long transmission lines  (3) Mho relays are best ... (1) and (3) (C) (2) and (4) (D) (1), (2) and (4)

Answer : Consider the following statements. Which of these statements are correct ?  (1) Reactance relays are preferred for ground fault relaying  (2) Impedance relays are most suitable for:protecting long transmission lines  (3) Mho relays are ... (1) and (3) (C) (2) and (4) (D) (1), (2) and (4)

Description : 30°, 60° and 90° connections are made in a directional relay to render the relay (A) Sufficient torque under fault conditions (B) Zero torque under fault conditions (C) Current grading (D) Time grading

Answer : 30°, 60° and 90° connections are made in a directional relay to render the relay Sufficient torque under fault conditions

Description :  For the protection of parallel feeders fed from one end, the relays used are: A) non-directional relays at the source-end and directional relays at the load-end B) non-directional relays at both the ... at the source-end and non-directional at the load-end D) directional relays at both the ends

Answer : For the protection of parallel feeders fed from one end, the relays used are: non-directional relays at the source-end and directional relays at the load-end

Description : Reactance relays are employed for Phase faults in : (A) Short lines (B) Medium lines (C) Long lines (D) Any line

Answer : Reactance relays are employed for Phase faults in : Short lines

Description : Explain construction and operation of induction type directional over current relay.

Answer : Directional overcurrent relay: Construction: It consists of two units: i) Non-directional Over-current unit ii) Directional power unit The directional unit consists of upper electromagnet ... closes the trip circuit. This operates circuit breaker which isolates the faulty section. 

Description : Define the following terms with respect to protective relays i) Relay time ii) Reset current iii) Plug setting multiplier and iv) Time setting multiplier

Answer : 1) Relay Time: The time interval between occurrence of fault and closure of relay contacts.  2) Reset Current: The value of current below which the relay resets and comes back to ... The adjustment arrangement provided for setting the operation time of relay is known as Time setting multiplier. 

Description : Electrical contact materials used in switches, brushes and relays must possess   (A) high thermal conductivity and high melting point  (B) Low thermal conductivity and low melting point   (C) High thermal conductivity and low melting point  (D) Low thermal conductivity and high melting point.

Answer : Electrical contact materials used in switches, brushes and relays must possess high thermal conductivity and high melting point 

Description : A Unified Power Flow Controller (FACTS controller) is a voltage source converter based (A) Inter-phase power controller (B) Static Compensator (C) Combination of series and shunt compensators (D) Solid-state series compensator

Answer : A Unified Power Flow Controller (FACTS controller) is a voltage source converter based Combination of series and shunt compensators

Answer : In order that current should flow without causing excessive heating or voltage drop, the relay contacts should have low contact resistance, be clean and smooth, be of sufficient size and proper shape.

Description : Explain operation of µP based relay with block diagram

Answer : Operation of Microprocessor (µP) based relay: The inputs from the power system through CTs and PTS are received by the analog Input receiver; they are sampled simultaneously or ... compares the dynamic inputs and decides accordingly to generate trip/alarm signal to the output device.

Description : The third generation relays - digital relays - are the basis of distribution system automation because of their: a. Self fault diagnostic capabilities b. Computing capabilities c. Easy interface for remote communication d. All of the above

Answer : The third generation relays - digital relays - are the basis of distribution system automation because of their: a. Self fault diagnostic capabilities b. Computing capabilities c. Easy interface for remote communication d. All of the above

Description : Differential relays are used for the protection of equipments against   (a) Internal faults (b) Over current (c) Reverse current (d) Reverse power

Description :  _____ is a bi-directional, fully duplex communication model that uses a persistent connection between client and server. A. Request-Response B. Publish-Subscriber C. Push-Pull D. Exclusive Pair

Answer : D. Exclusive Pair 

Description : ____ plans have clearly defined objectives. (a) Directional ; (b) Flexible ; (c) Specific ; (d) Standing

Answer :  (c) Specific ;

Description : "Male and female students perform equally well in a numerical aptitude test." This statement indicates a: (A) statistical hypothesis (B) research hypothesis (C) null hypothesis (D) directional hypothesis

Answer : (C) null hypothesis

Description : Successful Communication in classroom teaching is (A) Circular (B) Reciprocal (C) Directional (D) Influential

Answer : (B) Reciprocal

Description : Describe the working of directional coupler with neat diagram. 

Answer : Directional couplers are devices that will pass signal across one path while passing a much smaller signal along another path.  One of the most common uses of the directional coupler is to ... . The frequency determines the separation of the two holes as a fraction of the wavelength.  

Description : MIRV stands for (1) Multi-directional Independently Reoriented Vehicle (2) Multipurpose Integrally-targeted Revolutionary Vehicle (3) Multiple Independently-targetable Re-entry Vehicle (4) Multi-dimensional Independent Reentry Vehicle

Answer : Multiple Independently-targetable Re-entry Vehicle

Description : Light beam which is highly directional is called: (1) eraser (2) grazer (3) maser (4) laser

Answer : laser

Description : The transmission line distance protection relay having the property of being inherently directional is (A) impedance relay (B) MHO relay (C) OHM relay (D) reactance relay

Answer : The transmission line distance protection relay having the property of being inherently directional is MHO relay

Description : In induction type directional over current relay the driving torque is due to interaction of magnetic fields derived from (A) current in the potential coil (B) both voltage and current in the ... (C) directional element and non-directional element (D) non-directional element and the trip circuit

Answer : In induction type directional over current relay the driving torque is due to interaction of magnetic fields derived from directional element and non-directional element

Description : If the phase -angle of the voltage coil of a directional relay is 50°, the maximum torque angle of the relay is: (A) 130° (B) 100° (C) 50° (D) 25°

Answer : If the phase -angle of the voltage coil of a directional relay is 50°, the maximum torque angle of the relay is: 50°

Description : In a directional coupler:  (1) Isolation (dB) equals coupling plus directivity (2) Coupling (dB) equals isolation plus directivity (3) Directivity (dB) equals isolation plus coupling (4) Isolation (dB) equals (coupling) (directivity)

Answer : In a directional coupler: Isolation (dB) equals coupling plus directivity.

Description : According to Booker T. Whatley's recent analysis, planting the same crops as are planted on large farms will lead to economic disaster for the small farmer, who should plan a succession of high- ... farmer planting the same crops as are planted on large farms will lead to economic disaster; they 

Description : A bird sitting on a high tension electric wire does not get electrocuted because (1) it has high resistance (2) the body is earthed (3) it does not form a closed path for the flow of current (4) its feet are good insulators 

Answer : it does not form a closed path for the flow of current

Description : Zigbee specification are based on ______. A. 802.3 B. 802.11 C. 802.16 D. 802.15.4

Answer : D. 802.15.4 

Description : Classifying email as a spam, labeling webpages based on their content, voice recognition are the example of _____. A. Supervised learning B. Unsupervised learning C. Machine learning D. Deep learning

Answer : A. Supervised learning 

Description : List different types of tapes based on material of which they are made.

Answer : 1) Cloth or Linen tape 2) Metallic Tape 3) Steel Tape 4) Invar Tape 5) Fiber Glass wired Tape

Description : State different tapes used based on material of which they are made. 

Answer : Ans:1) Cloth or Linen tape 2) Metallic Tape 3) Steel Tape 4) Invar Tape 5) Fiber Glass wired Tape

Description : When jobs are grouped together based on a particular type of customer, this is known as….. (a) Job structuring ; (b) Formalization ; (c) Centralization ; (d) Departmentalization

Answer : (d) Departmentalization 

Description : Contingency theories of leadership are based on the belief that (a) there is no single style of leadership appropriate to all situations (b) there is a single style of leadership ... the interactions between the variables involved in a leadership situation and patterns of leadership behaviour.]

Answer : (a) there is no single style of leadership appropriate to all situations 

Description : While considering the seven leadership styles described by the leadership continuum, all of the following are variables that need to be considered for a manager, EXCEPT, (a) manager's preferred style ... style based on knowledge. (d) manager's preferred style based on confidence in upper management.

Answer : (d) manager's preferred style based on confidence in upper management. 

Description : Economics modes are (a) Based on some realistic assumptions ; (b) Based on hypothetical assumptions (c) Scientifically tested ; (d) Based on necessity

Answer : (a) Based on some realistic assumptions

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Answer : ANSWER: W -- BLUE-WHITE

Description : In the early 17th century, based on his observations with a telescope, Galileo Galilei attacked a belief espoused by the church. That belief was: w) that the earth was flat. x) the sky was a large dome ... seen. y) that the earth was at the center of the universe. z) there are no other planets.

Answer : ANSWER: Y -- THAT THE EARTH WAS AT THE CENTER OF THE UNIVERSE. 

Description : Generally a scientist's observations related to Experiment and testing are based on Options: A) Scientific principles B) House hold rules C) Self-imagination D) Self-experiences

Answer : A) Scientific principles

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