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Answer :

String efficiency is used for measuring the degree of utilization of SCR.

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Description : method for improving string efficiency 

Last Answer : The Methods of Improving String Efficiency:-   1) By reducing value of ‘m’ or (‘k’) by using longer cross arm. 2) By Making of ‘m’ or (‘k’) equal to zero 3) By grading Insulator. 4) By Using guard ring.

Description : Give the classification of the errors used in measuring instrument & state the reason for their occurrence.

Last Answer : Types of errors in measuring instruments:  A) Gross error: These are due to mistakes on the part of person using the instrument.  B) Systematic Error:  i) Instrumental Error: These ... multiplying factor.  C) Random error: These persist even after gross and systematic errors are removed. 

Description : Do you have any string?

Last Answer : There is string in out garage. And it’s string, not twine. I’ve used it to tie a stuffed pork tenderloin. I also have yarn, which is like furry string.

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Description : The number of insulator discs (each rated 11 kV) required in a suspension type insulator string of 220 kV line is 

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Description : Write a short note on Measuring Flask

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Description : What are the test and measuring instrument required in an Electrical depots?

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Description : Electrical Measuring Instruments

Last Answer : Electrical Measuring Instruments

Description : calibration and the need of calibration for measuring instruments.

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Description : Explain the essential toques in analog type measuring instruments.

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Description : State two purposes of calibration of measuring instruments.

Last Answer : Purposes of calibration of measuring instruments: - The purpose of calibration is to ensure that readings of an instrument are consistent with other instruments. It is also important in determining the ... will need to be calibrated periodically to make sure it can function properly and safely. 

Description : List three types of errors in measuring instruments. Give reasons of occurring for any one of them.

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Description : Define following terms related to measuring instruments: i) Sensitivity ii) Selectivity.

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Description : Name the different torque and their function in measuring instrument.

Last Answer : List of torques in analog instruments:  1. Deflecting torque  2. Controlling / restraining torque.  3. Damping torque.  1. Deflecting torque:  - To create deflection of pointer ... .  - Bring the pointer to standstill quickly.  - To minimize oscillations about final position. 

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Description : Explain magnetic effect employed in measuring instrument.

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Description : Describe systematic errors in measuring instruments. 

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Description : State the function of controlling torque in electrical measuring instrument.

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Description : Define: (i) Resolution, (ii) Calibration, with reference to electrical measuring systems.

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Description : Why energy meter is integrating type measuring instrument?

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Description : List any four effects employed in measuring instruments.

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Description : When measuring insulation resistance of cables using d.c. source, the galvanometer used should be initially short circuited because  (A) Cables have a low value of capacitance which draws a high ... high value of charging current (D) Cables have a low value of capacitance and initial resistance

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Last Answer : The desirable static characteristics of a measuring system are accuracy, sensitivity and reproducibility.

Last Answer : For measuring a very high resistance we should use Meggar.

Last Answer : For measuring current at high frequency we should use thermocouple instrument.

Description : 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 

Description : Which circuit is used as amplitude comparator?

Last Answer : Schmitt trigger circuit is used as amplitude comparator.

Description : How is a thyristor used to convert AC to DC?

Last Answer : thyristor

Description : SEER: Seasonal Energy Efficiency Ratio (SEER)

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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%.

Description :  Compare the salient features of LED and CFL based on: i] Lamp Efficiency ii] Life span 

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Description : "Efficiency of thermal power station is low". — Justify. 

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Description : Transformer efficiency

Last Answer : Transformer efficiency

Description : What is the efficiency of Class-B amplifier?  A) 68.50% B) 78.50% C) 88.50% D) 98.50%

Last Answer : What is the efficiency of Class-B amplifier?  A) 68.50% B) 78.50% C) 88.50% D) 98.50%

Description : The overall efficiency of Thermal Power Plant is equal to _______________ .  (A) Regenerative Cycle Efficiency (B) Renkine Cycle Efficiency (C) Carnot cycle efficiency (D) None of the above

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Description : A transformer operates 24 hours day at full -load. It's full -load efficiency is :  (A) equal all day efficiency (B) more than all -day efficiency (C) less than all -day efficiency (D) equal to maximum efficiency

Last Answer : A transformer operates 24 hours day at full -load. It's full -load efficiency is : equal all day efficiency 

Description : The rankine cycle efficiency of steam power plant is  (1) 60-80% (3) 30-45% (2) 45-80% (4) 20-30%

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Description : Transmission efficiency of a transmission line increases with the

Last Answer : Transmission efficiency of a transmission line increases with the increase in power factor and voltage

Description : For high efficiency of transfer of power, internal resistance of the source should be?

Last Answer : For high efficiency of transfer of power, internal resistance of the source should be less than the load resistance.

Last Answer : The efficiency of diesel locomotives is nearly 20 to 25 percent.

Last Answer : The overall efficiency of steam locomotive is around 5 to 10 percent.

Last Answer : D.C. generators are normally designed for maximum efficiency around full-load.

Last Answer : The condition for maximum efficiency for a D.C. generator is variable losses equal to constant losses.

Last Answer : The range of efficiency for shaded pole motors is 5% to 35%.

Last Answer : The efficiency of a properly designed synchronous motor will usually fall in range 85 to 95%.

Last Answer : Generators for peak load plants are usually designed for maximum efficiency at 50 to 75 percent full load.