why making capacity is more than breaking capacity?
Answer Posted / dipak
Here I want to add to Pratik answer. During fault, say on EHV line, line protection sense the fault and gives trip command to CB. The time involved from detection of fault to opening of CB(including response time of trip relay and CB opening mechanism) is about 30 to 40 msec. By this time, Sub transient and DC component of fault current get damped and CB actually get open in transient component of fault current.
However, during closing of CB, if fault is there on line(say dead fault), CB has to sustain Sub transient fault current during closing on dead fault. Hence, making capacity is always more than breaking capacity.
Also, CB is designed for considering its application as Generator CB because fault level is highest at generator terminal and therefore higher making and Breaking capacity is required for Generator CB.
| Is This Answer Correct ? | 1 Yes | 0 No |
Post New Answer View All Answers
What is a diode?
Q) Write VBscript code along with QTPscript code in QTP tool for below scenario 1. Launch yahoo site(i know) 2. Do loogin(i know) 3.Click inbox link(i know) 4.Go to every page of mail box and count no.of read mails and no.of unread mails(i know) 5.Store page numbers, read mail count and unread mail count in a new excel file sheet 6.Create 10 types of graphs on that data 7.Do logout and close site(i know) 8.Save new excel files with graph
please send me the previous year's question papers of jindal GET exams
Why the moulded plug comes with domestic appliances instead of assembled plug like anchor, Vinay 5/15 A.
Explain the construction of the conservator, operation and purpose, and draw the diagram of the conservator.
what is submersible pump?what is different between motor and sub motor?
I have a relay contact rated at 220v dc which is supplied with a 24vdc from the panel,for it to trip the dampers(24vdc).What if the application of the relay changes so that it should work at its rated 220vdc then will it work at 24vdc supply given or any other consideration needs to be taken .....
How Load Factor, Demand Factor, Diversity Factor etc best applied in designing an electrical circuit? Is it allowed to consider these factors in each and every panel in an electrical distribution system? Can any body suggest a good book for reference?
why not starting switch first connect in direct on line starter?????
The principle of switching circuits for different types of batteries in application of storage systems
If we impress a dc voltage of 230 V on an unloaded 230 V, 50 Hz transformer it wi A give high secondary voltage B burn out C give secondary voltage as per K D none of these
How many types of electrical earthing are there?
howmany electrician should maintain for a 1000 kva used plant... in kerala..
what is the transiant condition in alternator? and how it can be prevanted?
My question is abt backlog.I had dropped one subject in my second year, and completed this subject in the 3rd attempt, so how many backlogs i have got?1 or 3?plz sujjest the answer as soon as possible