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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795 views
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May 8, 2018
by
anonymous
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Last Answer : Air blast circuit breakers for 400 kV power system are designed to operate in 50 millisecond.
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209 views
1 answer
asked
Mar 20, 2018
by
anonymous

Why ACSR conductor is used for overhead lines?
Last Answer : It has high tensile strength
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2.7k views
1 answer
asked
Mar 10, 2018
by
anonymous

Draw and explain integrated duration curve used in system operation.
Last Answer : Diagram of integrated duration curve used in system operation: Explanation: Integrated duration curve is obtained from load duration curve. It is drawn in between load on Y-axis in KW/MW and the X- ... a particular time of a day can also be shown on a curve which is called as mass curve.
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128 views
1 answer
asked
Aug 3, 2019
by
anonymous

Differentiate between overhead transmission and underground transmission.
Last Answer : Points Overhead line Underground cable Capital cost Less More Erecting cost Less More Time require for completion of work Less More Flexibility More ... Space consumed Space consumed No space consumed Appearance Not good Very good
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64 views
1 answer
asked
May 22, 2020
by
anonymous

State properties of conductor material used for overhead conductor.
Last Answer : Following are the properties of conductor material:- 1. High conductivity :- Material should have high conductivity 2. High mechanical strength:- Material should have sufficiently high mechanical strength ... available & less costly. 9. Scrap Value: - Material should have high scrap value.
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131 views
1 answer
asked
May 5, 2020
by
anonymous


Why are overhead transmission lines not insulated?
Last Answer : Insulators are useful to help separate electrical conductors when they come into physical contact. Overhead Transmission Lines Are Not Insulated: The overhead transmission line is carrying extreme high voltage and ... a whole lot of thick insulation to absorb the heat produced by such high voltage.
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153 views
7 answers
asked
Aug 18, 2019
by
anonymous
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Why underground service connections are service connections are costly than overhead service connection
Last Answer : Reason: Underground service connection is given by underground cable. This cable is costly than bare conductor. Sometimes cable trench is required for cable laying, which requires additional cost. So underground service connections are costly than overhead service connection.
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124 views
1 answer
asked
Sep 18, 2018
by
anonymous

Define service connection and state types connection and state types of overhead service connection
Last Answer : Service Connection:- It is the input conductor or wire which is carried out from supply company (authorities) pole to consumers' main board or premises. Types of overhead service ... 1. Overhead service connection with Bare conductor 2. Overhead service connection with weather proof cable
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256 views
1 answer
asked
Sep 18, 2018
by
anonymous

A minimum clearance of 6.3 m to ground is required for overhead lines when operating voltages are : (A) less than 66 kV (B) lie between 66 kV and 110 kV (C) more than 165 kV (D) lie between 110 kV and 165 kV
Last Answer : A minimum clearance of 6.3 m to ground is required for overhead lines when operating voltages are : lie between 66 kV and 110 kV
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153 views
1 answer
asked
Apr 30, 2018
by
anonymous

lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is
Last Answer : lf a travelling-wave travelling along a loss-less overhead line does not result in any reflection after it has reached the far end, then the far end of the line is terminated into a resistance equal to surge impedance of the line
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104 views
1 answer
asked
Apr 26, 2018
by
anonymous

Last Answer : Overhead lines for power supply to tramcars are at a minimum height of 10 m.
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2.6k views
1 answer
asked
Mar 22, 2018
by
anonymous

Explain the lighting scheme to be designed for each of the following: i) Special ward in hospitals ii) Dentist’s Cabin
Last Answer : i) Special ward in hospital: For the patients in the wards, lighting should create a cozy and pleasant atmosphere. Lighting in the wards should be planned in such a way that it meets the specific ... we use such as cements and bonding agents that we use to restore your teeth back to health.
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190 views
1 answer
asked
May 3, 2020
by
anonymous

A circuit breaker is designed to protect an electrical circuit from damage caused by : (A) Over load (B) Short circuit (C) Over current (D) All of the above
Last Answer : A circuit breaker is designed to protect an electrical circuit from damage caused by : (A) Over load (B) Short circuit (C) Over current (D) All of the above
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106 views
1 answer
asked
May 8, 2018
by
anonymous

Last Answer : D.C. generators are normally designed for maximum efficiency around full-load.
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102 views
1 answer
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Mar 20, 2018
by
anonymous
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Last Answer : The efficiency of a properly designed synchronous motor will usually fall in range 85 to 95%.
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73 views
1 answer
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Mar 20, 2018
by
anonymous

Last Answer : Generators for peak load plants are usually designed for maximum efficiency at 50 to 75 percent full load.
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139 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : An efficient and a well designed protective relaying should have good selectivity and reliability, economy and simplicity, high speed and selectivity.
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136 views
1 answer
asked
Mar 19, 2018
by
anonymous

Last Answer : Relays can be designed to respond to changes in resistance, reactance or impedance voltage and current, light intensity, temperature.
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145 views
1 answer
asked
Mar 19, 2018
by
anonymous

Last Answer : The underground system cannot be operated above 66 kV.
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115 views
1 answer
asked
Mar 20, 2018
by
anonymous

Fuel Pump Operation
Last Answer : Most people know that their cars have fuel pumps, but they don't really know how they operate. Some even pay attention to their fuel pumps only when they have already malfunctioned. It is important ... check your fuel pump for any problems because a defective pump can be dangerous while on the road.
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13 views
1 answer
asked
May 5, 2021
by
anonymous
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State jumping operation.
Last Answer : Jumping up operation: This process makes metal shorter and thicker and carried out at near welding temperature. Metal can be either thickened at the ends of bars or swollen in the center.
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56 views
1 answer
asked
Jan 2, 2021
by
anonymous

With neat sketch explain four modes of operation of a TRIAC?
Last Answer : Modes of operation of a TRIAC: There are four different operating modes of TRIAC: 1) MT2 and gate are positive with respect to terminal MT1(Mode1) : Here terminal MT2 is positive ... junction P2-N2 is forward biased, current carriers are injected and therefore, the TRIAC is turned on.
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440 views
1 answer
asked
May 21, 2020
by
anonymous

What is PLL? Explain its operation with a block diagram.
Last Answer : PLL - A phase-locked loop or phase lock loop is a control system that generates an output signal whose phase is related to the phase of an input signal Block diagram ... to the input frequency. The phase - locked loop goes through three states free running capture and phase lock.
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268 views
1 answer
asked
May 2, 2020
by
anonymous

Draw & explain operation of phase detector.
Last Answer : In phase detector, the op-Amp basically acts as a zero crossing detector. If a sine wave is applied at the i/p, we get square wave at the op-Amp o/p (at point ... to two channel of the CRO. The time duration between the pulses corresponding to voltages represent the phase between them.
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127 views
1 answer
asked
May 2, 2020
by
anonymous

State the principle of operation of d.c. motor.
Last Answer : When a current carrying conductor is placed in a magnetic field, the conductor experiences the force. The magnitude of force is given by F = BIL newton where F – Force B – maximum flux density I – Current L – Length of conductor
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143 views
1 answer
asked
Apr 27, 2020
by
anonymous

operation of DSO with block diagram.
Last Answer : The input is amplified and attenuated with input amplifiers. The output of the input signal amplifiers feeds an analog to digital converter (ADC). There are numbers of ADC available. But the selection of ADC ... view the display on the CRT, the data from memory is reconstructed in analog form.
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235 views
1 answer
asked
Sep 4, 2019
by
anonymous

operation of ramp type DVM.
Last Answer : This is given to an input comparator which will compare two signals and generates the output. One input to the input comparator is from the input and another input is from the ramp. This input voltage and ... ground and output is given. This output will stop the flow of purchase from clock
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200 views
1 answer
asked
Sep 4, 2019
by
anonymous

operation of half wave rectifier type AC Voltmeter.
Last Answer : Half-wave Rectifier Voltmeter The d'Arsonval meter movement only responds to the average or dc value of the current through the moving coil. In order to measure alternating ... ) input voltage signal alternating signal needs to be rectified first by using diode rectifier to produce
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269 views
1 answer
asked
Sep 4, 2019
by
anonymous
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operation of whetstone bridge.
Last Answer : A Wheatstone bridge is widely used to measure the electrical resistance. This circuit is built with two known resistors, one unknown resistor and one variable resistor connected in the form of bridge. ... using a Wheatstone Bridge the unknown electrical resistance value can easily measure.
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100 views
1 answer
asked
Sep 4, 2019
by
anonymous
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State principle of operation of piezo-electric transducer. State its application.
Last Answer : The piezoelectric element used for converting mechanical movement into electric signals. The mechanical deformation generates charges and this charge appears as a voltage across the electrodes. ... destructive test (NDT) equipments 6. Piezoelectric materials are used in ultrasonic transducers.
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103 views
1 answer
asked
Aug 5, 2019
by
anonymous
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Explain the operation of UPS with a neat block diagram.
Last Answer : Uninterruptible-Power-Supplies (UPS): A block diagram of UPS system is shown in figure. It essentially consists of four major components: i)Rectifier (or battery charger) ii) ... . Due to fast action requirement, transfer switch can be implemented by fast acting semiconductor devices.
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3.3k views
1 answer
asked
Jul 25, 2019
by
anonymous

Describe principle of operation of Doppler type ultrasonic flow meter with diagram.
Last Answer : Diagram: Working: The flow meter consists of a crystal transducer mounted outside the pipe in which flow is to be measured. This transducer is a piezoelectric crystal which ... , so the frequency of the reflected wave is shifted to particle velocity, according to Doppler principle.
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169 views
1 answer
asked
Sep 8, 2018
by
anonymous

Explain the operation of advanced gas cooled reactor.
Last Answer : Operation:- Carbon dioxide or Helium is the gas used for transferring the heat produced form the reactor core to the Heat exchanger. The gas is pumped through the reactor core at high pressure. In heat ... The AGR was designed to have a high thermal efficiency 40 %. Steam pressure is 162 Kg/cm2
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74 views
1 answer
asked
Sep 7, 2018
by
anonymous

Describe the operation of N channel enhancement type MOSFET with diagram.
Last Answer : As its name indicates, this MOSFET operates only in the enhancement mode and has no depletion mode. It operates with large positive gate voltage only. It does not conduct when the ... of charge carriers attracted to the positive gate. Thus drain current is controlled by the gate potential.
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635 views
1 answer
asked
Sep 5, 2018
by
anonymous

Draw diagram of class A push-pull amplifier and explain its operation.
Last Answer : Class A Push-pull Amplifier: The circuit diagram of class A push-pull amplifier is as shown in the fig.(a). Operation: The resistors R1 and R2 along with Vcc provide the dc biasing so as ... Vcc is applied to the collectors of transistors Q1 and Q2 through the centretapped output transformer.
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153 views
1 answer
asked
Sep 5, 2018
by
anonymous

Describe operation of N-channel JFET
Last Answer : Operation of N-channel JFET 1) When VGS = 0 volt: When a voltage is applied between the drain and source with a DC supply voltage VDD with VGS = 0 V, the electrons flow from source ... to zero. The gate to source voltage at which current reduces to zero is called as pinch-off voltage.
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173 views
1 answer
asked
Sep 5, 2018
by
anonymous

What is photodiode? Draw the symbol and explain operation of photodiode.
Last Answer : A photodiode is a light detector that converts light into an electrical current. A photodiode is a semi-conductor device, with a p-n junction and an intrinsic layer between p and n layers ... current is independent of reverse bias voltage. Reverse current is mostly depends on the light intensity.
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577 views
1 answer
asked
Sep 4, 2018
by
anonymous

Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO
Last Answer : Which of the following thyristors can be used for high frequency of operation? A) TRIAC B) DIAC C) SCR D) GTO
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109 views
1 answer
asked
Jun 18, 2018
by
anonymous

A four -quadrant operation requires two full converters connected in (1) Series (3) Back to back (2) Parallel (4) Series Cascade
Last Answer : A four-quadrant operation requires two full converters connected in Parallel
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883 views
1 answer
asked
Apr 30, 2018
by
anonymous

An additional condition for parallel operation of three-phase transformers over single-phase transformers is that
Last Answer : An additional condition for parallel operation of three-phase transformers over single-phase transformers is that the transformers should belong to the same vector group
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144 views
1 answer
asked
Apr 29, 2018
by
anonymous

The operation of a ramp type Digital Voltmeter is based on the principle of (A) Voltage-to-current conversion. (B) Voltage-to-time conversion. (C) Current-to-time conversion. (D) Current-to-frequency conversion.
Last Answer : The operation of a ramp type Digital Voltmeter is based on the principle of Voltage-to-time conversion.
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133 views
1 answer
asked
Apr 28, 2018
by
anonymous

Last Answer : For the parallel operation of two or more D.C. compound generators, we should ensure that series fields of all generators should be either on positive side or negative side of the armature.
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179 views
1 answer
asked
Mar 20, 2018
by
anonymous

Last Answer : Necessary conditions required to be satisfied in order to ensure successful parallel operation of single phase transformers: 1. Only transformers having the same phase displacement between primary and secondary ... . 7. The phase sequence must be followed strictly on HV and LV side connection.
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197 views
2 answers
asked
Mar 19, 2018
by
anonymous

Enlist the different modes of operation of electronic counters and explain any two modes in details.
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489 views
0 answers
asked
Mar 2, 2018
by
anonymous

Explain the basic operation of an oscilloscope with necessary diagram for each section in detail.
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120 views
0 answers
asked
Mar 2, 2018
by
anonymous

Describe the basic SHA operation with the help of its four mode specifications.
Last Answer : Sample-and-hold amplifier (SHA) is a unity gain amplifier with a mode control switch where the input of the amplifier is connected to a time-varying signal. A trigger pulse at the mode control switch ... but other forms, such as optical and mechanical forms, are possible. Also denoted S/H.
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114 views
1 answer
asked
Mar 2, 2018
by
anonymous

parallel operation of MOSFET can be done more easily as compared to thyristor. why?
Last Answer : Parallel operation of MOSFET can be done more easily as compared to thyristor because the resistance of MOSFET is increases with increase in temperature. MOSFET have the positive temperature coefficient. In ... the parallel operation of MOSFET can be done more easily as compared to the thyristor.
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300 views
1 answer
asked
Dec 7, 2017
by
anonymous

Explain the series and parallel operation of MOSFET. Which is suitable and why?
Last Answer : Series operation of MOSFET: To increase voltage handling capability MOSFETs are connected in series. When the MOSFETs are connected in series each MOSFET should turn on and turn off ... on and turn off time and transconductance. Each MOSFET should share current equally.
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534 views
1 answer
asked
Sep 15, 2017
by
anonymous
