what is the function of LBB relay

Answer Posted / selvakumar.j

LBB- local breaker backup protection. after issued the trip command by the relay ,the breaker should be open . if breaker not operate after received trip command ,LBB protection will operated and trip the upstream or downstream breaker to protect the circuit.

Is This Answer Correct ?    19 Yes 5 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

what is capacitor voltage transformer?? how it is different from potential transformer?

1777


what material is used in capaciter

1596


what are the things that can cause a three phase motor to crawl?

2997


how to find out cable size if load is 2800 watts, 230 volts AC supply and load distance is 1800 meters

1232


why Induction Generators are not "Black start" ? and apart from WTGs where this types of generator are generally used?

2302






witch pump used in wtp

1706


If not into production, how far did you follow the design and why did not you see it into production?

1791


why and how voltage sharing in transformer, during magnetic balance test ?

1932


why Y CONNECTION IS BETTER INTERMS OF EFFICIENCY AND P.F FOR A LAOD LESS THAN 40% AND WHY AFTER DELTA IS BETTER FOR > 40%

1569


What is the tube exial fan?

1795


how is the incoming cable size calculated for a given current rating of a panel??

1544


An 8 pole, 50 Hz, 3-phase IM is loaded to a poing where pull out torque will occur. The rotor resistance per phase is 0.3 ohm and motor stalls at 650 rpm. The slip when motor stalls is A 1 B 0 C 13.33% D 10.33%

1505


What are the types of class b amplifier?

716


Is it possible to measure correct value of earth resistance & cable insulation ristance with out disconncting earth lead & both sides of cable ends? If not, any other method to measure ER & CIR with out disconneting from the system.

1760


How to Calculate the Fault Level of Electrical Installation

1859