Large internal faults are protected by (a) merz price percentage differential protection (b) mho and ohm relays (c) horn gaps and temperature relays (d) earth fault and positive sequence relays

Large internal faults are protected by (a) merz price percentage differential protection (b) mho and ohm relays (c) horn gaps and temperature relays (d) earth fault and positive sequence relays
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Answer :

(a) merz price percentage differential protection
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Related questions

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Last Answer : (b) internal short-circuits

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The inverse definite mean time relays are used for over current and earth fault protection of transformer against?

Last Answer : The inverse definite mean time relays are used for over current and earth fault protection of transformer against internal short-circuits.

Large internal faults are protected by?

Last Answer : Large internal faults are protected by merz price percentage differential protection.

Give the limitations of Merz Price protection.

Description : Give the limitations of Merz Price protection.

Last Answer : Since neutral earthing resistances are often used to protect circuit from earth-fault currents, it becomes impossible to protect the whole of a star-connected alternator. If an earth-fault occurs ... secondary quantities and a possibility of current through the relay even when there is no fault.

Mention the short comings of Merz Price scheme of protection applied to a power transformer.

Description : Mention the short comings of Merz Price scheme of protection applied to a power transformer.

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Last Answer : (a) Rewireable fuse

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Last Answer : (a) motors

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Last Answer : (d) short-circuits

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Last Answer : (d) all of the above

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The unit to measure the flow of water is - (1) Micro Mho (2) Ohm meter (3) Milli curie (4) Cusecs

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The unit to measure the flow of water is (1) Micro Mho (2) Ohm meter (3) Milli curie (4) Cusecs

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Last Answer : Cusecs

A _______ is used to measure the stator % winding temperature of the generator. (a) thermocouple (b) pyrometer (c) resistance thermometer (d) thermometer

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Last Answer : (c) resistance thermometer

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Last Answer : (d) all of the above

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Description : Will main generator differential relay pick up for generator earth faults? 

Last Answer : No earth fault current limited to 5A, while differential setting is 10%. 

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Last Answer : d) Answers b and c

How Transformer Protection provided for internal faults?

Description : How Transformer Protection provided for internal faults?

Last Answer : 1.Bucholz Relay (1st Stage Alarm and 2nd Stage Trip) 2.Sudden Pressure Relay (1st Stage Alarm and 2nd Stage Trip) 3.Pressure Relief Valve (1st Stage Alarm and 2nd Stage Trip) 4.Pressure Switch ... 8.Gas Temperature Indicator (Alarm) 9.Silicon Breather (Passive - no alarm) 10.Smoke Detector (Alarm)

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Description : Why 2 types of earth fault relays in 6.6 kV side of transformers?

Last Answer : I – Trips 6.6 kV breakers only. It gives primary protection for 6.6 kV bus bars. I1 – Trips the both HT and LT breakers. It acts as a backup to ref and also acts as backup to bus bar earthfault relay. 

Reactance relays are employed for Phase faults in :

Description : Reactance relays are employed for Phase faults in : (A) Short lines (B) Medium lines (C) Long lines (D) Any line

Last Answer : Reactance relays are employed for Phase faults in : Short lines

Which relays are used for phase faults on long line?

Last Answer : Impedance relays are used for phase faults on long line.

Mho relay is usually employed for protection of

Description :  Mho relay is usually employed for protection of (A) Short lines (B) Medium lines (C) Long lines (D) Any line

Last Answer : Mho relay is usually employed for protection of long lines.

For an Resistive Load and Inductive load considered for switching operation of circuit breaker, Switching of which load is difficult and Why?

Description : For an Resistive Load and Inductive load considered for switching operation of circuit breaker, Switching of which load is difficult and Why?

Last Answer : In case of switching resistive load, current and voltage will be in phase i.e,when during current zero voltage also will be zero in case of resistive load. Hence the voltage at the ... maximum. This results in re-striking of arc once again. Therefore switching inductive load will be difficult