Protection by fuses is generally not used beyond?

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asked Mar 20, 2018 by anonymous

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asked Sep 1, 2018 by anonymous

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asked Jun 4, 2018 by anonymous

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asked Jun 23, 2020 by anonymous

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asked Jun 4, 2018 by anonymous

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asked Apr 10, 2018 by anonymous

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asked Jun 4, 2018 by anonymous

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asked Jun 23, 2020 by anonymous

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asked Jun 23, 2020 by anonymous

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Last answer: Differential Protection Scheme for Bus bar: Under normal conditions, the sum of the currents entering the bus bar zone is equal to those leaving it and no current flows through the relay ... of these currents will flow through the relay coil causing opening of circuit breaker of bus-bar.

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asked Jun 23, 2020 by anonymous

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asked Jun 23, 2020 by anonymous

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asked Jun 23, 2020 by anonymous

List two limitations of Differential-Protection scheme for transformer.

Last answer: Limitations of Differential Protection Scheme of Transformer: 1) Due to the magnetization characteristics of the CTs used, the ratio errors change with respect to the circulating currents. 2) ... & improper operation. 5) Inrush of magnetizing current may lead to inadvertent operation.

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asked Jul 21, 2019 by anonymous

Explain differential protection of busbar.

Last answer: Differential protection Scheme for bus bar: Under normal conditions the sum of the currents entering the bus bar zone is equal to those leaving it and no current flows through the relay ... . The difference of these currents will flow through the relay coil causing opening of circuit breaker.

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asked Jul 21, 2019 by anonymous

Explain over-current protection of transformer.

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asked Jul 21, 2019 by anonymous

Explain negative phase sequence protection of alternator.

Last answer: Negative phase sequence protection of alternator: Unbalanced loading on alternator mainly causes the negative sequence currents which generate the negative sequence components of magnetic fields. These fields ... components due to unbalance and operates the relay which further operates CB.

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asked Jul 21, 2019 by anonymous

Explain fault bus protection scheme.

Last answer: Fault bus protection of busbar: In this scheme, the substation is so designed that every fault on the bus bar is converted to earth fault. Under normal operating conditions, there is no current flowing ... This results in operation of relay to actuate trip coil of CB to trip the circuit.

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asked Jul 21, 2019 by anonymous

Explain distance protection of transmission line with neat sketch diagram.

Last answer: Distance protection of Transmission line: Distance protection scheme uses impedance relay. The relay operation is based on the impedance (or distance) between the relay and point of fault. Figure shows ... than ZL and impedance relay operates which operates the CB and line is protected.

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asked Jul 21, 2019 by anonymous

Write down limitation of differential protection of transformer.

Last answer: Limitations of differential protection of transformer: 1) Due to the magnetization characteristics of the CTs used, the ratio errors change with respect to the circulating currents. 2) The pilot wires ... current (higher imbalance) due to which accuracy of sensing & operation is decreased.

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asked Jul 21, 2019 by anonymous

How can we use CT and PT for protection purpose?

Last answer: CT and PT for Protection purpose: Current transformer (CT) and Potential transformer (PT) are instrument transformers, which are used in conjunction with protective relays for protection purpose. The CT ... from the healthy part. In this way the CT and PT can be used for protection purpose.

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asked Jun 17, 2018 by anonymous

For complete protection of a three-phase line:

For complete protection of a three-phase line: A) three Phase relays and three Earth fault relays are required B) three Phase relays and two Earth fault relays are required C) two Phase relays and two Earth fault relays are required D) two Phase relays and one Earth fault relay are required

Last answer: For complete protection of a three-phase line: two Phase relays and one Earth fault relay are required

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asked May 24, 2018 by anonymous

A loss of excitation protection scheme for large generating unit employs

A loss of excitation protection scheme for large generating unit employs A) under frequency relays B) offset Mho relay C) reactance relay D) percentage differential relay

Last answer: A loss of excitation protection scheme for large generating unit employs offset Mho relay

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asked May 22, 2018 by anonymous

For complete protection ofa 3-phase line:

For complete protection ofa 3— phase line: (1) Three phase and three—earth fault relays are required (2) Three phase and two—earth fault relays are required (3) Two phase and two—earth fault relays are required (4) Two phase and one-earth fault relays are required

Last answer: For complete protection ofa 3— phase line: Two phase and one-earth fault relays are required

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asked Mar 20, 2018 by anonymous

Synchronous motors are generally not self-starting because?

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asked 4 days ago by anonymous

Which among the following statements is true regarding International Date line ? (1) It is 180° Longitude (2) It is a straight line (3) It is a big circle (4) It is a curved line beyond earth

Last answer: It is 180° Longitude

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asked Sep 1, 2018 by anonymous

High-voltage testing equipment is generally used in

High-voltage testing equipment is generally used in a. Routine testing Laboratories b. Research Laboratories c. Both of the above d. None of the above

Last answer: High-voltage testing equipment is generally used in a. Routine testing Laboratories b. Research Laboratories c. Both of the above d. None of the above

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asked Jun 17, 2018 by anonymous

Which motor is generally used in Tap Recorders?

Which motor is generally used in Tap Recorders? A) universal motor B) reluctance motor C) split phase motor D) hysteresis motor

Last answer: Which motor is generally used in Tap Recorders? A) universal motor B) reluctance motor C) split phase motor D) hysteresis motor

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asked May 24, 2018 by anonymous

Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator Reason (R) :

Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator Reason (R) : by using either capacitor (or) resistor in one of the arms of the bridge, the frequency of a wein bridge oscillator can be varied (A) Both (A) & (R) are true & (R) is correct explanation of (A) (B) Both (A) & (R) are true but (R) is not the correct explanation of (R). (C) (A) is true but (R) is false (D) (A) is false but (R) is true

Last answer: Assertion (A) : Wein bridge oscillator is generally used as a variable audio frequency oscillator Reason (R) : by using either capacitor (or) resistor in one of the arms of the bridge, the frequency of a wein bridge oscillator ... ) (A) is true but (R) is false (D) (A) is false but (R) is true

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asked Apr 29, 2018 by anonymous

The storage battery generally used in electric power stations is

The storage battery generally used in electric power stations is (1) zinc carbon battery (2) lead acid battery (3) nickel cadmium battery (4) lithium -ion battery

Last answer: The storage battery generally used in electric power stations is lead acid battery

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91 views 1 answer

asked Apr 12, 2018 by anonymous

Current ratings of MCB for Air conditioners is generally used as _________.

Current ratings of MCB for Air conditioners is generally used as _________. A. 10/15 Amp B. 5/10 A C. 20/25 Amp D. none of these

Last answer: Current ratings of MCB for Air conditioners is generally used as 10/15 Amp.

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85 views 1 answer

anonymous · Answer 1 · 2018-03-20T03:36:01+0000

answered Mar 20, 2018 by anonymous

Protection by fuses is generally not used beyond 100 A .

Protection by fuses is generally not used beyond?

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