A good voltage regulation of a transformer means?

Minimum voltage regulation occurs when the power factor of the load is?
Last Answer : Minimum voltage regulation occurs when the power factor of the load is leading.

224 views 1 answer

asked Mar 19, 2018 by anonymous

A transformer can have regulation closer to zero?

Last Answer : A transformer can have regulation closer to zero on leading power factor.

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asked Mar 19, 2018 by anonymous

A ferro resonant transformer regulation is also known as?

A ferro resonant transformer regulation is also known as?
Last Answer : A ferro resonant transformer regulation is also known as constant current transformer.

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asked Mar 19, 2018 by anonymous

Identify the increasing order of voltage regulation of the following dc generators a same load :

Identify the increasing order of voltage regulation of the following dc generators a same load : (A) differential compound, shunt and under compound (B) shunt, differential compound and ... C) under compound, shunt and differential compound (D) shunt, under compound and differential compound
Last Answer : Identify the increasing order of voltage regulation of the following dc generators a same load : under compound, shunt and differential compound

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asked Apr 30, 2018 by anonymous

The voltage regulation in magnetic amplifier type voltage regulator is effected by?

Last Answer : The voltage regulation in magnetic amplifier type voltage regulator is effected by varying the reactance.

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asked Mar 20, 2018 by anonymous

In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?

In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are?
Last Answer : In a given transformer for a given applied voltage, losses which remain constant irrespective of load changes are hysteresis and eddy current losses.

152 views 1 answer

asked Mar 19, 2018 by anonymous

The voltage transformation ratio of a transformer is equal to the ratio of?

The voltage transformation ratio of a transformer is equal to the ratio of?
Last Answer : The voltage transformation ratio of a transformer is equal to the ratio of secondary induced e.m.f. to primary induced e.m.f.

166 views 1 answer

asked Mar 19, 2018 by anonymous

If a transformer is switched on to a voltage more than the rated voltage?

If a transformer is switched on to a voltage more than the rated voltage?
Last Answer : If a transformer is switched on to a voltage more than the rated voltage its power factor will deteriorate.

97 views 1 answer

asked Mar 19, 2018 by anonymous

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

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.

181 views 1 answer

asked Jul 27, 2019 by anonymous

Step-down transformer converts high voltage and low current into:

Step-down transformer converts high voltage and low current into: (A) How voltage and high current (B) High voltage and low current (C) Low voltage and high current (D) None of the above
Last Answer : Step-down transformer converts high voltage and low current into: Low voltage and high current

125 views 1 answer

asked May 8, 2018 by anonymous

The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be :

The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be : (A) 34.64 kVA (B) 75 kVA (C) 20 kVA (D) None of the above
Last Answer : The kVA rating of Three-phase transformer with Voltage = 200V and Current = 100A will be : 34.64 kVA

199 views 1 answer

asked May 8, 2018 by anonymous

What is a capacitor voltage transformer?

What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up low voltage signals and provide extra high voltage B) It is a transformer used in power systems ... in power systems to step down extra high voltage signals and provide low voltage D) None of these
Last Answer : What is a capacitor voltage transformer? A) It is a transformer used in power systems to step up low voltage signals and provide extra high voltage B) It is a transformer used in power systems ... power systems to step down extra high voltage signals and provide low voltage D) None of these

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asked Apr 29, 2018 by anonymous

What is impulse voltage of transformer?

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asked Mar 10, 2018 by anonymous

does the high voltage side of Transformer winding have more number of turns?

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.

157 views 1 answer

asked Sep 30, 2017 by anonymous

Define line regulation and load regulation.

Define line regulation and load regulation.
Last Answer : Load regulation is the ability of the power supply to maintain its specified output voltage over changes in the load. Line regulation is the ability of the power supply to maintain its specified output voltage over changes in the input line voltage.

329 views 3 answers

asked Jul 24, 2019 by anonymous

Classify hydro-electric power plants according to water flow regulation and explain in brief.

Classify hydro-electric power plants according to water flow regulation and explain in brief.
Last Answer : Classification of hydro-electric power plants according to water flow regulation of water flow:- 1. Large reservoir power plant 2. Run-off river (ROR) power plant with poundage 3. Run-off River ... depends upon rate of flow of water Initial cost is less Its purpose is to generate electricity.

84 views 1 answer

asked Sep 7, 2018 by anonymous

Define load and line regulation.

Define load and line regulation.
Last Answer : 1. Load regulation : The load regulation indicates how much the load voltage changes when the load current changes. The load regulation is defined as: % Load regulation = (VNL-VFL) / VFL *100 ... the power supply. A well-regulated power supply can have a line regulation of less than 0.1%.

101 views 1 answer

asked Sep 5, 2018 by anonymous

The unit of speed regulation of a governor is :

The unit of speed regulation of a governor is : (A) Hz (B) Hz/MW (C) Hz/MVA (D) rpm/MVAR
Last Answer : The unit of speed regulation of a governor is : Hz/MW

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asked Apr 29, 2018 by anonymous

Which motor has the best speed regulation?

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asked Mar 15, 2018 by anonymous

A transformer cannot raise or lower the voltage of a D.C. supply because?

Last Answer : A transformer cannot raise or lower the voltage of a D.C. supply because Faraday's laws of electromagnetic induction are not valid since the rate of change of flux is zero.

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asked Mar 19, 2018 by anonymous

The no load current in a transformer lags behind the applied voltage by an angle of about?

Last Answer : The no load current in a transformer lags behind the applied voltage by an angle of about 75°.

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asked Mar 19, 2018 by anonymous

When a given transformer is run at its rated voltage but reduced frequency, its?

Last Answer : When a given transformer is run at its rated voltage but reduced frequency, its core flux density is increased.

110 views 1 answer

asked Mar 19, 2018 by anonymous

What are the necessary tests to determine the efficiency, voltage regulation, and temperature rise of winding & insulation of transformer?

What are the necessary tests to determine the efficiency, voltage regulation, and temperature rise of winding & insulation of transformer?
Last Answer : 1.Direct loading test 2.Open circuit test 3. Short circuit test 4. Sumpner's or back to back test

8 views 1 answer

asked Dec 27, 2021 by itszee

51 A transformer has negative voltage regulation when its load power factor is A. Zero B. Unity C. Leading D. Lagging

51 A transformer has negative voltage regulation when its load power factor is A. Zero B. Unity C. Leading D. Lagging
Last Answer : C. leading

153 views 1 answer

asked Jul 21, 2021 by jyoti kurekar

For given applied voltage, with the increase in frequency of the applied voltage?

For given applied voltage, with the increase in frequency of the applied voltage?
Last Answer : For given applied voltage, with the increase in frequency of the applied voltage eddy current loss will remain unchanged.

238 views 1 answer

asked Mar 19, 2018 by anonymous

Explain the effect of Harmonics on the Transformer.

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.

130 views 1 answer

asked May 22, 2020 by anonymous

List two special feature of welding transformer.

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

153 views 1 answer

asked May 22, 2020 by anonymous

State two applications of isolation transformer

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.

54 views 1 answer

asked May 22, 2020 by anonymous

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

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%.

279 views 1 answer

asked May 22, 2020 by anonymous

Equivalent circuit of transformer

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

381 views 2 answers

asked May 17, 2020 by anonymous

Single phase transformer

Single phase transformer
Last Answer : Single phase Transformer Transformer

261 views 1 answer

asked May 16, 2020 by anonymous

What is the use of transformer?

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.

160 views 1 answer

asked May 15, 2020 by anonymous

Transformer on DC

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

248 views 1 answer

asked May 10, 2020 by anonymous

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

115 views 0 answers

asked Apr 28, 2020 by anonymous

State any four characteristics of core type transformer.

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.

132 views 1 answer

asked Jul 27, 2019 by anonymous

Explain construction and working of single phase Auto transformer.

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

347 views 1 answer

asked Jul 26, 2019 by anonymous