410 views
Primary and Backup Protection

1 Answer

Answer :

Primary and Backup Protection

image



 

•B,D,G,I are the primary protection.

•A,C,H,J are the backup protection.

•About 90% of faults are clear by Primary Protection.

•So remaining 10% fault are occurred due to failure in tripping of circuit breaker, failure in detection of fault, failure in current transformer or power transformer etc.

•In power system primary protection is the first line of defense.

•Backup protection start protecting the system when primary protection is fails.

•So the remaining 10% fault is cleared with the help of backup protection.

      The types of Backup protection are

1.Relay backup (single relay consist of primary and backup)

2.Breaker backup (primary and backup are on same station)

3.Remote backup (primary and backup are on different station)

4.Centrally Co-ordinated backup (primary is at various station  and backup is at control room with computer)

Like 0 like

Please log in or register to answer this question.

Related questions

399 views

Last Answer : Discrimination between main and back up protection is provided by the use of relays which are slow.

1 answer
1 view

Description : Backup entire Office 365 domain?

Last Answer : Need Answer

1 answer
3 views

Description : Erasing Old Backup Files?

Last Answer : What are you backing up to?

1 answer
12 views

Description : How to Install a Backup Camera in My Car

Last Answer : How to Install a Backup Camera in My Car Safety needs to be the number one part of owning a car. Surprisingly, many tragic accidents occur when cars back out of driveways. Children may ... connections are tight. Jostling around in a moving vehicle will easily loosen a poorly done wire connection.

1 answer
672 views

Description : Blind spot is a point in the zones of protection where

Last Answer : Blind spot is a point in the zones of protection where No protection is available.

1 answer
554 views

Description : A relay used for protection of motors against overload is :  (A) Impedance relay (B) Electromagnetic attraction type (C) Thermal relay (D) Buchholz's relay

Last Answer : D

2 answers
629 views

Description : A negative sequence relay is used for protection of  (1) Generator (3) Motor (2) Transformer (4) Long Transmission lines

Last Answer : A negative sequence relay is used for protection of Generator 

1 answer
4.6k views

Description : For protection of rotating machines against lightning surges _______ is used.  (1) lightning arrester (2) capacitor (3) combination of lightning arrester and capacitor (4) lightning conductor and arrester

Last Answer : For protection of rotating machines against lightning surges combination of lightning arrester and capacitor is used. 

1 answer
123 views

Description : Reactance relay is normally preferred for protection against

Last Answer : Reactance relay is normally preferred for protection against earth faults

1 answer
3.0k views

Description : Surge absorbers are used for protection against

Last Answer : Surge absorbers are used for protection against low voltage high frequency oscillations

1 answer
175 views

Last Answer : Protection by fuses is generally not used beyond 100 A .

1 answer
164 views

Last Answer : A fuse in a motor circuit provides protection against short-circuit and overload.

1 answer
83 views

Last Answer : Overfluxing protection is recommended for generator transformer of the power plant.

1 answer
100 views

Last Answer : Over voltage protection is recommended for hydro-electric generators, steam turbine generators, gas turbine generators.

1 answer
2.6k views

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

1 answer
313 views

Last Answer : The single phasing relays are used for the protection of three phase motors.

1 answer
97 views

Last Answer : For the protection of power station buildings against direct strokes the requirements are interception, conduction and dissipation.

1 answer
104 views

Last Answer : The delay fuses are used for the protection of motors.

1 answer
238 views

Last Answer : A thermal protection switch can protect against overload.

1 answer
192 views

Description : Define: primary and secondary distribution system 

Last Answer : i) Primary Distribution:  It is a 3-phase, 3-wire transmission line connected in between receiving substation to Distribution substation. OR It is link between receiving substation & ... substation to consumer line. OR It is link between distribution transformer substation & consumer. 

1 answer
189 views

Description : Write example of each type (i) Primary transducer (ii) Active transducer (iii) Electrical transducer (iv) Digital transducer

Last Answer : (i) Active transducer:-Thermocouple, piezoelectric, photovoltaic cell (ii) Primary transducer:- Bourdon tube, bellows, (iii) Electrical transducer.:- LVDT,RVDT, Hall effect, strain gauge, ... , optical pyrometer, radiation pyrometer (iv) Digital transducer:- Linear Encoder, digital taco generator

2 answers
94 views

Description : Compare primary and secondary instruments.

Last Answer : Primary instruments  Secondary instruments  Gives magnitude of quantity in terms of physical constants of instrument  Gives reading directly of the quantity measured.  Need no calibration  ... .  e.g. magnetic meter, induction meter, hotwire meter and electrostatic meter 

1 answer
121 views

Last Answer : The primary reason for low power factor is supply system is due to installation of induction motors.

1 answer
88 views

Last Answer : Primary winding of a transformer could either be a low voltage or high voltage winding.

1 answer
286 views

Description : In a transformer the resistance between its primary and secondary should be?

Last Answer : In a transformer the resistance between its primary and secondary should be infinity.

1 answer
82 views

Description : What is the definition of a primary instrument?

0 answers
2 views

Description : A similar to Gs Richcopy 360, can work on Linux?

Last Answer : Have you tried rsync?

1 answer
0 views

Description : How can I back up my entire C drive?

Last Answer : answer:If you can start from another disk, then none of those files will be in use. I like UBCD4Win (Ultimate Boot CD for Windows) for jobs like this. http://www.ubcd4win.com/ You need a Windows® XP CD, with at least Service Pack 1, to burn the UBCD4Win.

1 answer
2 views

Description : What is the best home NAS solution with DLNA and remote replication?

Last Answer : Something like this? Datto

1 answer
1 view

Description : How do I restore from a clone?

Last Answer : answer: and why not Time Machine? It does everything you just described. In addition to individual files, Time Machine does full restores from Time Machine in the case of full system drive failure are easy ... of this assuming you're on Mac OS X-right? (you were at MacWorld Expo after all).

1 answer
6 views

Description : Can anyone recommend a good, durable protection case for iPod Touch 4th gen?

Last Answer : I would highly recommend an Otterbox case. I have the Defender series case for my 3gen iPod touch. It's not perfect, but it provides better protection than any other case I've seen, and I like the ... ago, but that was only because I dropped my iPod and the case cracked. The ipod was fine though.

1 answer
63 views

Description : What is the purpose of Overload Protection in a motor circuit?

Last Answer : Ans. The Overload Protection is used in a motor circuit to protect it from sustained over currents.

1 answer
2 views

Description : Protection scheme for internal faults in a three phase star delta connected transformer

0 answers
13 views

Description : Limitations of differential protection scheme of the altanetor

0 answers
16 views

Description : Car Leather Protection

Last Answer : Your girlfriend and your leather car interior have many things in common. Both are tough but incredibly sensitive. Both are cold and are very hard to please. Both need a lot of attention and ... differences too. Unlike your girlfriend, leather is not something you want to get down and dirty with.

1 answer
30 views

Description : 3 phase 11KV to 4 10000 KVA alternator has neutral Earth through a resistance of 1 ohm the machine has current balance protection while operate upon of balance Karan exceed 18% of full load determine percentage of winding and protected against ground fault

0 answers
2.6k views

Description : Explain in detail over-voltage protection.

Last Answer : Over-voltage protection: Over-voltage protection to the thyristor is provided using: i) R-C Snubber circuit ii) Non-linear resistor Thyrector A) Snubber Circuit: It is basically a ... returns to its high resistance state. Thyrector is normally placed across the supply terminals.

1 answer
1 view

Description : What should I look for in buying a carbon monoxide detector?

Last Answer : I think the best is a multipurpose smoke detector and carbon monoxide detector wired in with battery back up. If you have old smoke detectors you might want to consider this. Otherwise, you can get a plug ... and still want a monoxide detector, so then the plug in is a nice addition in that case.

1 answer
1 view

Description : Why don't I need a welding mask when I watch a welding video on YouTube?

Last Answer : because there are no actual sparks? because the brightness of the screen is limited? why do you not go blind when you look at a painting of the sun?

1 answer
2 views

Description : How often would you wax a new vehicle?

Last Answer : Never.

1 answer
2 views

Description : What types of STDs do lesbians need to protect themselves from?

Last Answer : Paper cuts from the scissor party?

1 answer
2 views

Description : How to get rid of caterpillars?

Last Answer : answer:Have you identified what kind of caterpillars these are? They may be beneficial to have in your garden. Leave the nests alone. And really, just let the birds feast in your garden.

1 answer
3 views

Description : If hoodlums, thugs, criminals, or whatever you wish to call them, did not know which clerk was armed and which ones were not, they would seriously think twice before attempting a robbery?

Last Answer : answer:I notice you left nigger off your list, which is really what this question is about. Black people finally standing up for themselves in the face of systematic oppression really has you people's ... you've robbed a man of everything, he's no longer in your power. - Aleksandr Solzhenitsyn

1 answer
0 views

Description : Rand Paul to file class action lawsuit against Obama administration supporting NSA spying. Will you sign up?

Last Answer : answer:I’ve already thrown in with the EFF, an organization that also opposes the NSA ‘s shenanigans, but that I actually agree with far more than I agree with Rand Paul. But yes, it is best for us to not let this issue fade away.

1 answer
1 view

Description : What is the difference between a US embassy vs. consulate and what determines which foreign nations get one or the other?

Last Answer : There is only one Embassy in a foreign country. For instance, Mexico or the UK has only one Embassy each in America. But, they may have several Consulates that are like branches of the ... a consulate office, much larger staff, and the Ambassador to the country usually works from the Embassy.

1 answer
2 views

Description : Home defense rethink. What do you guys think?

Last Answer : answer:Maybe, but I want an attacker / invader to be incapacitated, not just hurt (and pissed off). So my current home (and office, and car) defensive weapon of choice is wasp spray. It ... keep the can sitting on my desk, where it elicits questions from approximately one or two people per year.

1 answer
1 view

Description : Small dogs vs. large dog, make the case?

Last Answer : I have a 45 lb dog. with a big bark, and loves a lap. I believe it is best of both worlds. I tend to prefer bigger dogs, but I love cuddling with this bugger. Not the one in my profile. :(

1 answer
1 view

Description : Do snakes like strawberries?

Last Answer : I don’t think they like strawberry plants themselves, but if rodents are attracted to the strawberries, this will draw snakes.

1 answer
2 views

Description : Why not suit reactor techs in space suits?

Last Answer : There's a difference between solar radiation and nuclear radiation. Solar radiation is often intense UV and infrared light. These forms of radiation are harmful, but can be blocked. Nuclear radiation, on ... body without interacting. So no, space suits do not work to shield neutrons and gamma rays.

1 answer
4 views

Description : How was Welding discovered?

Last Answer : answer:According to Encyclopedia Britannica: Welding is a technique used for joining metallic parts usually through the application of heat. This technique was discovered during efforts to ... and Stanislav Olszewski (Poland) are considered the inventors of modern welding apparatus. Source

1 answer
...