# In a power or distribution transformer about 10 percent end turns are heavily insulated?

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In a power or distribution transformer about 10 percent end turns are heavily insulated to withstand the high voltage drop due to line surge produced by the shunting capacitance of the end turns.

## Related questions

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Last Answer : The transformer laminations are insulated from each other by thin coat of varnish.

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Last Answer : High voltage winding in a transformer has more number of turns.

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Description : Increasing the number of turns of wire on the secondary of a transformer will  (A) Decrease the secondary current (B) Increase the primary current (C) Have no effect on the secondary current (D) Increase the secondary current

Last Answer : Increasing the number of turns of wire on the secondary of a transformer will Decrease the secondary current

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Last Answer : yes High Voltage side of Transformer winding have more number of turns. and low voltage side of Transformer winding have less number of turns.

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Description : Write selection criteria of distribution transformer with any four points.

Last Answer : Selection Criteria for Distribution Transformer:  i) Ratings - The kVA ratings should comply with IS:2026 ( Part l )-1977*. The noload secondary voltage should be 433 volts for transformers to be ... is not necessary. vi) Cooling - The transformers covered in this group are generally ONAN, AN

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Last Answer : In a distribution system, in order to improve power factor, the synchronous capacitors are installed at the receiving end.

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Last Answer : The power transformer is a constant main flux device.

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Description : The maximum load that a power transformer can carry is limited by its?

Last Answer : The maximum load that a power transformer can carry is limited by its voltage ratio.

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Description : Turns ratio

Last Answer : Turns ratio formula

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Description : lt the length, number of turns and area of a coil are  doubled, the inductance of the coil

Last Answer : lt the length, number of turns and area of a coil are  doubled, the inductance of the coil is quadrupled

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Description : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... Current will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

Last Answer : What would happen if a power transformer designed for operation on 50 Hz (frequency) were connected to a 500 Hz (frequency) source of the same voltage:  (A) Eddy Current and Hysteresis losses will be ... will be too much high  (C) Transformer may start to smoke and burn  (D) No effect

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Description : A transformer has negative voltage regulation when its load power factor is   (1) Zero (2) Unity (3) Leading (4) Lagging

Last Answer : 0

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Description : To protect the power transformer (Y-Y with neutral grounded) against fault, what type of connection do the CTs have ?

Last Answer : To protect the power transformer (Y-Y with neutral grounded) against fault, what type of connection do the CTs have ? Δ-Δ connection

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Description : Explain transformer isolated drive circuits providing both signal and power.

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Last Answer : The maximum efficiency of a distribution transformer is at 50% full load.

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Description : TRANSMISSION AND DISTRIBUTION MCQ

Last Answer : 51. It is difficult to maintain oil filled cables. (a) Yes (b) No Ans: a 51. In capacitance grading a homogeneous dielectric is used. (a) Yes (b) No Ans: b 52. In congested areas where excavation is ... The metallic sheath may be made of lead or lead alloy or of aluminium. (a) Yes (b) No Ans: b

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Description : Distribution Boards –

Last Answer : Ans. a. Sub & Main Distribution Boards b. Schedule Maintenance.

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Description : Grid distribution system

Last Answer : Grid distribution system:-  In this system, when the feeder or loop or ring is charged (energized) by two or more than two substations from two or more than two different generating stations then it is known as “Grid distribution system. In this system only one feeder is utilized at a time.

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Description : Define: primary and secondary distribution system

Last Answer : i) Primary Distribution:  It is a 3-phase, 3-wire transmission line connected in between receiving substation to Distribution substation. OR It is link between receiving substation & ... substation to consumer line. OR It is link between distribution transformer substation & consumer.

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Description : State the condition for selecting site for distribution substation.

Last Answer : Following condition should be considered while selecting site for distribution sub-station:-  1. Near load center :  Sub-station should be located near load center to reduce cost of Transmission and ... free from earthquake :  To avoid damage to sub-station area should be free earth quake.

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Description : State the classification of distribution substation.

Last Answer : The classification of distribution substation. 1. Pole mounted distribution substation 2. Plinth mounted distribution substation 3. Compact/prefabricated distribution substation 4. ... Indoor distribution substation 6. Outdoor distribution substation 7. Mobile distribution substation

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Description : State the losses in secondary distribution system.

Last Answer : The losses in secondary distribution system: a) Technical losses: 1. Due to poor voltage 2. Due to unbalance load 3. Due poor quality of transformer & its components 4. Due to poor quality ... of induction type of energy meter. 3. Lack of administration. 4. Energy theft 5. Unmetered supply

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Description : Advantages of Grid distribution scheme

Last Answer : Advantages of Grid distribution scheme 1. Supply to distribution transformer center is given through two different generating stations or major generating stations 2. It has highest reliability to ... highest reliability to maintain supply even when there was maintenance on any one feeder.

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Description :  different types of distribution scheme.

Last Answer : According to scheme of connection: -  a) Radial (Tree) distribution system  b) Ring mains (Loop) distribution system  c) Grid (interconnected) distribution system OR Types of ... distribution system  b) Ring mains (Loop) distribution system  c) Grid (interconnected) distribution system

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Description : comparison between Feeder and Distribution

Last Answer : Sr.No Feeder Distributor 1 It is link between receiving substation & distribution transformer   It is link between distribution transformer substation & consumer  2 ... loading point is at substation only   Distributors loading point is throughout its length.

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Description : requirements of a distribution system

Last Answer : Following requirements of a distribution system.  1. Layout should be simple in design. 2. It should have less initial cost 3. The distribution system should have minimum distribution ... stability of existing distribution system. 15. Time required for completion of work should be less.

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Description : Why radial distribution system used for short distance ?

Last 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.

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Description : Explain following techniques related to energy conservation in transmission and distribution system. (i) By balancing phase currents (ii) Variable technical losses (I2R losses).

Last Answer : (i) Balancing Phase currents: Proper (healthy balanced) three phase loads always draw equal currents in all lines but single phase loads in the 3 phase 4 wire system or loads connected between two ... . 11) Minimize I2R losses. 12) Balance the load currents. 13) Regulate the system voltages.

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Description : Explain with schematic diagram direct distribution of solar energy.

Last Answer : Explain with schematic diagram direct distribution of solar energy: Solar energy reaching earth's surface consists of two components: i) Direct solar energy, ii) Diffused solar energy. Direct solar energy ... radiation. It is very intense radiation and it can produce sun burns and shadows.

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Description : The permissible voltage variation in transmission and distribution system is:  (A) ± 0.1% (B) ± 1% (C) ±10% (D) ± 25%

Last Answer : The permissible voltage variation in transmission and distribution system is: ±10%

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Description : The skin effect in conductors is due to non uniform distribution of current in it and major portion of current is near the _______ of conductor.  (1) Surface (2) Center (3) Complete cross section area (4) Axis

Last Answer : The skin effect in conductors is due to non uniform distribution of current in it and major portion of current is near the Surface of conductor.

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Description : The main criterion for selection of the size of a radial distribution system is

Last Answer : The main criterion for selection of the size of a radial distribution system is voltage drop

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Description : Precise control of reactive current flow entering the transmission and distribution systems can be minimized by using (A) synchronous condenser (B) static VAR capacitor (C) capacitor bank (D) thyristor switched reactor in parallel with capacitor

Last Answer : Precise control of reactive current flow entering the transmission and distribution systems can be minimized by using (A) synchronous condenser (B) static VAR capacitor (C) capacitor bank (D) thyristor switched reactor in parallel with capacitor

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Last Answer : Service mains are the conductors, which connect the consumer's terminals to the distribution.

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Description : 77 The transformer laminations are insulated from each other by A. Mica strip B. Thin coat of varnish C. Paper D. Any of the above

Last Answer : B. Thin coat of varnish

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Last Answer : The efficiency of a power transformer is of the order of 98 percent.

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Description : Explain the effect of Harmonics on the Transformer.

Last Answer : Effect of Harmonics on the Transformer:  1. Core loss: Harmonic voltage increases the hysteresis and eddy current losses in the lamination. The amount of the core loss depends on ... small core vibrations.  5. Saturation problem: Sometimes additional harmonic voltage causes core saturation.

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Description : List two special feature of welding transformer.

Last Answer : Special features of welding transformer: i) It is a step down transformer that reduces the source voltage to a voltage desired according to the demands of the welding process. ii) Having large primary turns and less ... V ii) Secondary voltage - 40 to 60 V iii) Secondary current - 200 to 600 A

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Description : State two applications of isolation transformer

Last Answer : Applications of isolation transformer: i) Isolates the load equipment from supply ground: ii) Reduction of voltage spikes iii) It acts as a decoupling device. iv) Protects loads from harmonic distortion.

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Description : State why a transformer always have an efficiency of more than 90%.

Last Answer : As transformer is static device with no moving parts, the losses due to friction & windage are completely absent. Hence transformer has efficiency of more than 90%.

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Description : Equivalent circuit of transformer

Last Answer : Equivalent Circuit Diagram of Transformer Referred to Primary: V1 -Primary Input voltage I1 - Input Current I0- Exciting current/ No load current Im- Magnetizing component ... equivalent of secondary terminal voltage ZL- Load impedance ZL ′- Primary equivalent of load impedance

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Description : Single phase transformer

Last Answer : Single phase Transformer Transformer

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Description : What is the use of transformer?

Last Answer : The use of transformer  is to do lower or raise  the voltage or currents in an electrical  circuit.  That's quite so simple.

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Description : Write about transformer on DC.

Last Answer : Transformer on DC : Transformer cannot work on DC. Transformer works on electromagnetic induction principle. Electromagnetic induction principle means when flux linking with coil changes and EMF induced in it ... winding insulation will burn. https://youtu.be/TVp_0fIfxqY

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Description : Even at no-load, a transformer draws current from the mains. Why?

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Description : State and justify which of the following two transformers is better:  Transformer A = 4% voltage regulation  Transformer B = 6% voltage regulation

Last Answer : Transformer A with 4% voltage regulation is better.  Justification: Voltage regulation refers to the percentage change in secondary voltage when load is changed from no-load to full-load with primary voltage ... 4% voltage regulation, which is less as compared to 6% of transformer B, it is better.

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Description : State any four characteristics of core type transformer.

Last Answer : Characteristics of core type transformer: i) It has one window. ii) It has one magnetic circuit. iii) Core surrounds the winding. iv) Average length of core is more. v) Area of cross ... Better cooling for winding. vii) Mechnical strength is comparatively less. viii) Repair and maintenance is easy.

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Description : Explain construction and working of single phase Auto transformer.

Last Answer : Construction of single phase auto transformer: (i) It has only one winding wound on a laminated circular magnetic core. (ii) The core is made of silicon steel stampings. (iii) The two terminals of the ... help of handle. 5) The same transformer can be used as step-up or step down auto-transformer