what is the main function of lbb
protection

Answer Posted / shailesh

The main function of LBB to get protection (To trip breaker)
when main breaker not trip due any reasons.

Is This Answer Correct ?    1 Yes 1 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what is the difference between electrical choke and electronic choke?

2096


Write the force balance equation of ideal dashpot element.

850


What are the disadvantages of autotransformer?

657


What is the loss of transformer of 220kv/11kv, 63/80 MVA and 18.05% impedance

1556


Q.1:What protection will be used on HT and LT side of 33/0.4 KV, MVA transformer. Indicate capacities of protective device to be used. Q.2:Which types of back-up protections are used in the power transformers? What do you understand by the term over travel in the relay? Q.3:How star and delta connected winding transformer are provided from earth fault

1710






When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<

1682


What is the classification of hydro projects based on installed capacity?

687


What is shutdown of electrical sub station?

1954


why we cannot protect 100% winding of an alternator by using differential protection?

1748


why can the rotor of 3 phase slip ring induction motor not be a 2 phase rotor?

1566


can you please send me the technical questions and aptitude questions of honeywell and jindal steel electrical engg. question paper my e-mail ID is(kkesavanraj@gmail.com)

1547


can you send me the placement papers of electrical engg. from companis like NTPC,DRDO,IOCL,HPCL,BPCL etc.?If,plz send as soon as possible.Thanks.

1689


How to measure power in 2 or 4 or n phase circuit? Please give me a formula.

1469


What is the difference between acs 550 & acs 850

5380


What magnetic circuit is formed in berry-type constructions and why?

663