Answer Posted / tpfasil200

Local breaker backup or breaker fail relay(LBB)..It is used when the trip command is given and the breaker fails to open due to some mechanical problem. The protection is time delayed and initiated by all trip conditions.On LBB operation, busbar protection is initiated, as all the breakers connected to that particular bus to which the circuit is connected have to be tripped.I t also trips the tie breaker and sends a direct trip command to the other end breaker.

the winding of Generator and Motor is star or in delta ? and why

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What is method of calculating the fault current for a MDB, 50KW, 3PH, 415V, 50HZ?

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what is your aim

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we are having 15kw and 3kw motor both can run in same time , instead of using copper we are using ug aluminium cable , 35 sq.mm is suitable for its current carrying capacity..?

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What is the Nyquist criterion regarding control systems?

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How to confirm the Phase shifting Transformer VECTOR GROUP relation , as below ZNy11.45d10.45-ZNYy0.15d11.15

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What is “pu” in electrical engineering?

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In Generator How suction compression power and exhaust works ?

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What is Tachometer used to measure?

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operation of protection relay watchdog contact?

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please tell me when we start motor without load in star or delta connection whose current above condition,pl write formula

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If 22 KV HT line, Current transformer is 25/5 then how to calculate multiplying factor.

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what is cause of static electricity? I experience shock when i touch metal equipment in a room ,furher check shows earth leakage showing 80ma at the DB near to the 400 MCCB?

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What is difference between start imitation and start interlock for 3 phase motor protection ?

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what is the defination of Cable database? What are the points are considered while preparing cable database? Is there any sample available for cable database?

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