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

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 : 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. 

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.

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

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

Description : Explain over-current protection of transformer.

Answer : Over-Current Protection of Transformer: Simple over-current & earth fault protection of transformer against external shortcircuit and excessive overloads is shown in the above figure. The ... trip command to the circuit breaker and the transformer is disconnected from load or fault.

Description : A series resistance is added to the over-current relay in a bus bar differential protection scheme which: a. Helps to develop some voltage across it which otherwise should appear across the relay and is ... the effects of CT saturation and lowers the pickup value of the relay d. All of the above 

Answer : A series resistance is added to the over-current relay in a bus bar differential protection scheme which: a. Helps to develop some voltage across it which otherwise should appear across the relay and is ... the effects of CT saturation and lowers the pickup value of the relay d. All of the above 

Description : Which of the following is the least expensive protection for over current in low voltage system?  (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker

Answer : Which of the following is the least expensive protection for over current in low voltage system?  (A) Rewireable fuse (B) Isolator (C) Oil Circuit breaker (D) Air break circuit breaker

Description : State any four relays used for catenary protection. State function of each relay.

Answer : Relays Used for Catenary Protection: 1. MHO relay: Wrong coupling protection. 2. MHO relay: Over current protection at farthest point. 3. Over current relay: Over current protection against faults near substation 4. Under voltage relay: Protection against faults far away from substation. 

Description : State use of any four relays for the protection of traction transformer. 

Answer : Relays for the protection of traction transformers:  Inverse time over current relay as back up protection on primary (HV side) - over current protection of transformer and other equipment.  ... .  Buchholz relay - protection from incipient earth or inter winding faults inside the transformer

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

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

Description : In a static over-current relay, inverse time characteristics are obtained by   (a) A differentiating circuit (b) An integrating circuit (c) A transistor amplifier (d) A transistor switch

Answer : B

Description : The burden of protective Current Transformer (CT) is specified in

Answer : The burden of protective Current Transformer (CT) is specified in Volt - Ampere

Description : The operating point of a protective current transformer is near the

Answer : The operating point of a protective current transformer is near the Ankle point

Answer : Current transformers (CT) : Current transformer (CT) actually step down the high current to low current for the operation of relays. Current transformer is use for measurement of ... use for relay. This is about potential transformer.

Description : Describe over current relay with time-current characteristic.

Answer : Over current relay with time-current characteristics:- 1. Definite time over current relay: Operating time is constant, the relays operates after a predetermined time when the current exceeds the pickup ... of fault current and definite time characteristics at higher values of fault current.

Description : Write the formulas for each of the following statements: (a) current is the time rate of change of charge (b) charge is current accumulated over a period of time.

Description : Explain in detail over-voltage protection.

Answer : Over-voltage protection: Over-voltage protection to the thyristor is provided using: i) R-C Snubber circuit ii) Non-linear resistor Thyrector A) Snubber Circuit: It is basically a ... returns to its high resistance state. Thyrector is normally placed across the supply terminals.

Description : State the nature of protection provided for following types of faults; 1) Over voltage 2) Under voltage 3) High air pressure in air circuit 4) Low air pressure in air circuit

Answer : Ans:  1) Over voltage: Controlled through tap changing, only an alarm needs to be provided for attention of crew.  2) Under voltage: voltage below 17.5 kV is not desirable. A no volt ... 4) Low air pressure in air crcuit: Relay senses low pressure in air circuit and trips the relevant CB.

Answer : Over voltage protection is recommended for hydro-electric generators, steam turbine generators, gas turbine generators.

Description : factors to be considered while designing feeders ? 

Answer : Following factors are to be considered while designing the Feeder:  1) Current carrying capacity of conductor:- Conductor should have high current carrying capacity. While voltage drop consideration is ... time consuming.  5) Power Factor of load should be consider while designing

Description : Reactive power compensation in feeders leads to (A) poor voltage profile (B) improved voltage profile (C) negative and zero sequence currents (D) expensive voltage regulators

Answer : Reactive power compensation in feeders leads to improved voltage profile

Description : A drainage pattern where a river is joined by its tributaries approximately at right angles is ____________ (1) Dendritic (2) Trellis (3) Rectangular(4) Radial

Answer : Trellis

Description : A layer in which the grain size changes vertically through the layer is called: a) Foliated b) Cross-bedded c) Graded bedding d) Is not observed in nature

Description : What is ‘AGMARK’? (1) It is a marketing seal issued on the graded agricultural commodity (2) It stands for agricultural marketing (3) It represents agricultural management and regulation (4) None of these

Answer :  It stands for agricultural marketing

Description : The ‘graded profile’ of a river course is a (1) smooth curve from source to mouth. (2) smooth curve in the upper course. (3) smooth curve in the middle course. (4) smooth curve in the lower course. 

Answer : smooth curve from source to mouth.

Description : Define the term multimode fiber,step index fiber,Graded index fiber and single mode fiber. 

Answer : Multimode fiber: A fiber having core radius large,supports hundreads of modes & lesser bandwidth also suitable for short distance communication is called Multi mode fiber.  Step index ... & larger bandwidth also suitable for long distance communication is called single mode fiber.

Description : The innovation strategy is characterized by……………… (a) A mixture of loose with tight properties ; (b) Looser controls for new undertakings (c) Low specialization and low formalization ; (d) Tight controls over current activity 

Answer : (c) Low specialization and low formalization ;

Description : A resistor of value R/2 is connected in parallel with a resistor of value R/3. The voltage drop across the parallel combination is V. The total current supplied by the voltage source is: w) 2 V/R (read: 2 V over R) x) 3 V/R (read: 3 V over R) y) 4 V/R (read: 4 V over R) z) 5 V/R (read: 5 V over R)

Answer : ANSWER: Z -- 5 V/R

Description : When running under no-load condition and with over excitation, armature current Ia drawn by a synchronous motor

Answer : When running under no-load condition and with over excitation, armature current Ia drawn by a synchronous motor Leads the applied voltage

Description : What is meant by feeder in power system?

Answer : A feeder line is a peripheral route or branch in a network which connects smaller or more remote nodes with a route or branch carrying heavier traffic. The term is applicable to any system based on a hierarchical network.

Description : Systems for Protection from negative sequence current is provided normally for (a) Transformers (c) Transmission lines (b) Generators (d) Motors

Answer : Systems for Protection from negative sequence current is provided normally for Transmission lines

Description : Differential relays detect internal faults in 3-phase transformers by (A) zero sequence currents (B) positive sequence currents (C) negative sequence currents (D) both positive and negative sequence currents

Description : The phase lag produced by transportation relays?

Answer : The phase lag produced by transportation relays increases linearly with frequency.

Description : 1. Which is used extensively for genetic engineering in plant? 2. The Centre-State financial distribution takes place on the recommendation by which ministry? 3. At the time of short-circuit, what ... first in producing teak? 20. By whom was the agitation against the partition of Bengal led?

Answer : Answer : 1 1. Agrobacterium tumefaciens 2. Finance Minister 3. Increases heavily 4. India 5. Warangal 6. Bentham 7. September 8 8. RNA 9. Eyre 10. M. G. Ranade 11. Attorney General 12. ... Mission 16. October 8 17. Salinity 18. Government of India Act, 1935 19. Thailand 20. Surendranath Banerjee

Description : Distinguish among radial ply, cross ply & belted bias types tyres

Answer : Sr. No. Radial ply tyre Cross ply tyre Belted bias Type  1 Plies are running radially straight from bead to bead Piles are running diagonally opposite from bead to bead. The basic construction is ... tyre. Costlier than radial ply & cross ply tyre 8

Description : The tapetum in which radial walls breakdown early are called as

Answer : The tapetum in which radial walls breakdown early are called as – Amoeboid tapetum

Description : Radial zonation of shoot apex is found in

Answer : Radial zonation of shoot apex is found in – Gymnosperms 

Description : What type of drainage pattern would you expect to find where the main streams are parallel and very long and the edge of the folded sedimentary rock (weak and resistant) forms long parallel belts? (A) Dendritic (B) Rectangular (C) Radial (D) Trellised

Answer : (D) Trellised 

Description : Two bodies of equal mass are moving in circular paths at equal speed. The first body moves in a circle whose radius is twice as great as that of the second. The ratio of the centripetal or radial acceleration of the first body to that of the second is: w) 1 to 4 x) 1 to 3 y) 1 to 2 z) 1 to 1

Answer : ANSWER: Y -- 1 TO 2

Description : If xylem and phloem are arranged in the same radius, such a vascular bundle is called : (1) collateral (2) bicollateral (3) concentric (4) radial

Answer : collateral

Description : A particle moving with uniform speed can possess :  (a) radial acceleration (b) tangential acceleration © both radial and tangential accelerations (d) neither radial nor tangential acceleration

Description : Differentiate between cross ply and radial-ply tyre.

Answer : Differentiate between cross ply and radial-ply tyre.

Description : Radial drilling machine

Answer : Radial drilling machine: A radial drilling machine is illustrated in Fig. This is really meant to drill holes in bigger and heavier work pieces, which cannot be manipulated so that the centre of the hole ... and a hole drilled at the required location, without shifting the heavy work piece.

Description : State advantages and disadvantages of radial distributor system. 

Answer : Advantages of radial distributor system: 1. Design of layout is simple. 2. Capital cost & Erecting cost is less as there is only one feeder. 3. Time required for completion of ... maintain supply to consumers when there is maintenance on feeder. 3. Voltage fluctuations are more.

Description : Why radial distribution system used for short distance ? 

Answer : Because of following disadvantages radial distribution system is not used for long distance:  Since there is only one feeder to DTC feed at one point so, 1) There is no reliability ... more time for fault finding & repairing Hence radial distribution system is used for short distance.

Description : The overhead radial distribution is preferred to (A) reduce voltage fluctuations (B) increase service reliability (C) distribute power at low voltage (D) distribute power to long distances 

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