Thursday, February 16, 2023

MCB: MINIATURE CIRCUIT BREAKER OPERATION BASIC

What is MCB?

MCB is a device designed to protect an electrical circuit's wiring from the serious damage which would be caused if it has to carry a current that is too high for the diameter of its wires.

The MCB or Miniature Circuit Breaker is actually working for both electrical circuits' make or break switch and protection device fuse.

Likely normal fan/light switches, MCB also can operate manually as circuit ON or OFF; its specialty is, it can break the circuit automatically to protect from overcurrent.

Fuse is the very first protection device for an electrical circuit. A fuse is actually nothing but a thin wire that is enclosed in a protective casing and plugged into the circuit.

The fuse carries the same circuit current that flows in any other point, but it is designed so that when the current reaches too high unexpectedly, the fuse burns up and breaks and protects safe the wiring from damage.

What Are the Differences Between Fuses And MCB?

The limitation of fuses is that it works only once, every time burning the fuses, it needs to replace with a new fuse wire. To overcome this limitation and avoid fuse-wire replacement hassle, miniature circuit breakers or MCBs are commonly used rather than conventional fuses in low-voltage electrical network systems.

MCB also works for overcurrent and opens the circuit as soon as the current reach unsafe levels. The main difference between MCB and fuse is that they can use over and over time.

Sponsored:

How MCB works?

The basic MCB or miniature circuit breaker consists of a simple switch to operate automatically at the danger level of over-current. The main part as a known trip unit of MCB actually does this mechanism. The working principle of the miniature circuit breaker or  MCB is as below-
  • A simple bimetallic strip design for MCB in such a way that when the current limit crosses a safe level then unsafe high current bends the thin strip to break the current flow;
  • An electromagnet uses in MCB that magnetizes by electricity; magnetized electromagnet experiences magnetic forces which pull or push to break the circuit when the current flow reaches an unsafe level;
  •  Semiconductor devices are used for breaker operating in advanced circuit breakers. This is very much précised to monitor the circuit current level, when reaching the current at a preset value then the circuit breaker can operate. This is expensive which makes it limited use in more sophisticated devices.
Due to the nature of fault current amount and time- bimetallic protection against overload current and electromagnetic protection against short-circuit current is suitable.    
Basic Components of MCB
The basic components of MCB are shown in the MCB construction figure below:
      1. Internal components of MCBTunnel Terminal;
      2. Jaw Terminal;
      3. Arc Runner;
      4. Arc Chamber;
      5. Thermo-metal Element;
      6. Calibration Mechanism;
      7. DIN Rail Mounting;
      8. Moving Contact;
      9. Fixed Contact;
      10. Latch Mechanism;
      11. Operating Handle;
      12. Coil Assembly;
      13. Trip Bar.
 
MCB Operating Mechanism
The operating mechanism of MCB is limited to manual and auto combination. It can break the circuit during excessive overcurrent, but can not make the circuit again, need manual operation.

Latch has three operation positions- ON, OFF & TRIPPED. In the close condition of MCB, the latch is positioned at ON, and manually switching off the MCB, the latch is positioned at OFF. When MCB automatically breaks the circuit to save from over-current then the latch is positioned at TRIPPED.
MCB Operating Time & Current
Type of MCB Tripping Current Operating Current
Type  B 3 to 5 times of full load current 0.04 to 13 seconds
Type  C 5 to 10 times of full load current 0.04 to 5 seconds
Type  D 10 to 20 times of full load current 0.04 to 3 seconds

For example, let us consider an MCB with a rating is 6A; 

What will be the short circuit current for different classes like B, C & D?

For class B, the short circuit current will be 3 to 5 times its rated current. So short circuit current will be 6x3 to 6x5 or 18A to 30A;

For class C, the short circuit current will be 5 to 10 times its rated current. So short circuit current will be 6x5 to 6x10 or 30A to 60A;

For class D, the short circuit current will be 10 to 20 times its rated current. So short circuit current will be 6x10 to 6x20 or 60A to 120A;

So, the class should be select considering the interruption of the short circuit current label.

What Is the Difference Between MCB, MCCB, RCCB & ELCB

MCB: Miniature Circuit Breaker

Circuit Braker Types

Physiognomies



  1. Rated current up to 100 A;
  2. Tripping point not non-adjustable;
  3. Thermal-magnetic operation.
  4. Three types according to pole:
MCB- SP (Single Pole)
MCB- DP (Double Pole)
MCB- TP (Triple Pole)
Sponsored:

MCCB: Molded Case Circuit Breaker
Physiognomies
  1. Rated Current up to 100A ;
  2. Tripping point adjustable/non-adjustable;
  3. Thermal and thermal-magnetic operation.
RCCB: Residual Current Circuit Breaker
Physiognomies
  1. Residual current rating 10mA, 30mA, 100mA, 300mA, 500mA, 1000mA & adjustable 2000mA;
  2. Not operate for over current;
  3. Detect the difference between phase and neutral current; if difference found breaks the circuit immediately;
  4. Mainly used for shock protection;
  5. Nuisance tripping may happen due to aged or less performed appliances.
ELCB: Earth Leakage Circuit Breaker
Also known as Ground Fault Circuit Interrupter, in short GFCI.
Physiognomies
  1. ELCB works on earth leakage current;
  2. ELCB or GFCI was designed only to detect a current flowing in the safe ground or earth wire.
If it is helpful, help others to hit share.


47 comments:

  1. Very usefull informaton thanks for sharing this link share for more about MCCB Working Principle MCCB Rating and MCCB Current Setting Click here

    ReplyDelete
  2. Hi my family member! I wish to say that this article is amazing,
    great written and include almost all significant infos.

    I would like to see extra posts like this .

    ReplyDelete
  3. I dugg some of you post as I cogitated they
    were extremely helpful very beneficial.

    ReplyDelete
  4. Hello! I’ve been reading your weblog for some time now and finally got the bravery
    to go ahead and give you a shout out from Lubbock Texas!
    Just wanted to tell you keep up the fantastic job! It is the best time
    to make some plans for the future and it's time to be happy.
    I have read this post and if I could I desire to suggest you few interesting things or tips.
    Maybe you could write next articles referring to this article.
    I want to read more things about it! It is perfect time
    to make a few plans for the long run and it is time to be happy.
    I've learn this put up and if I could I wish to suggest you some fascinating issues or tips.

    Perhaps you could write next articles relating to this article.
    I desire to read more issues about it! http://foxnews.co.uk

    ReplyDelete
  5. You got a very great website, Gladiola I observed it through yahoo.

    ReplyDelete
  6. This paragraph will help the internet users for building up new website or even a blog from start to
    end.

    ReplyDelete
  7. Wow that was odd. I just wrote an extremely long comment but
    after I clicked submit my comment didn't show up. Grrrr...
    well I'm not writing all that over again. Anyways, just
    wanted to say wonderful blog!

    ReplyDelete
  8. Wonderful work! That is the kind of info that
    are meant to be shared across the web. Disgrace on Google for no longer positioning this publish higher!
    Come on over and talk over with my website . Thank you =)

    ReplyDelete
  9. This is a good tip especially to those fresh to the
    blogosphere. Brief but very precise info? Appreciate your sharing this one.
    A must read post!

    ReplyDelete
  10. I was just seeking this info for a while. After 6 hours of continuous Googleing, finally I got it
    in your website. I wonder what's the lack of Google strategy that
    don't rank this kind of informative web sites in top of the list.
    Generally the top web sites are full of garbage.

    ReplyDelete
  11. Spot on with this write-up, I really think this site needs a great deal more attention. I'll
    probably be returning to see more, thanks for the advice!

    ReplyDelete
  12. Great article! We are linking to this great content on our site.
    Keep up the great writing.

    ReplyDelete
  13. Hi there, I discovered your blog by means of Google whilst searching
    for a similar matter, your site came up, it appears good.
    I've bookmarked it in my google bookmarks.[X-N-E-W-L-I-N-S-P-I-N-X]Hello there, just was aware of your blog through Google, and located that it's really informative.
    I am gonna watch out for brussels. I'll be grateful in the event you continue this in future.
    A lot of people can be benefited from your writing.
    Cheers!

    ReplyDelete
  14. It's not my first time to pay a visit this web page, i am browsing this site
    dailly and take pleasant facts from here daily.

    ReplyDelete
  15. I was very pleased to find this website.
    I wanted to thank you for ones time for this particularly fantastic read!!
    I definitely really liked every bit of it and i also have you book-marked to check
    out new things in your website.

    ReplyDelete
  16. Pretty element of content. I just stumbled upon your web site and
    in accession capital to assert that I acquire
    actually loved account your blog posts. Any way I will be subscribing to your feeds and even I fulfillment you get entry to persistently rapidly.

    ReplyDelete
  17. I am actually pleased to glance at this web site posts which carries lots
    of helpful facts, thanks for providing these information.

    ReplyDelete
  18. It's great that you are getting thoughts from this piece of writing as well as from our dialogue made at
    this place.

    ReplyDelete
  19. I have not checked in here for a while as I thought it was getting boring,
    but the last several posts are great quality so I guess I'll add you back to my
    daily bloglist. You deserve it my friend :)

    ReplyDelete
  20. Its like you read my thoughts! You appear to understand
    so much about this, like you wrote the e-book in it or something.
    I think that you simply can do with some % to
    force the message house a little bit, but other than that,
    that is magnificent blog. An excellent read. I'll definitely
    be back.

    ReplyDelete
  21. Yay google is my king helped me to find this great site!

    ReplyDelete
  22. I'm gone to convey my little brother, that he should also pay a quick visit this weblog on regular basis to get updated from
    most recent information.

    ReplyDelete
  23. Sản phẩm được phân phối độc quyền tại Việt Nam.

    ReplyDelete
  24. I was just seeking this info for a while. After
    six hours of continuous Googleing, finally I got it in your website.
    I wonder what's the lack of Google strategy that don't rank this kind of informative
    web sites in top of the list. Usually the top websites are full of garbage.

    ReplyDelete
  25. Everyone loves it when folks come together and share views.

    Great website, keep it up!

    ReplyDelete
  26. Hola! I've been reading your site for a long time now and finally got the courage to go ahead and give you a shout out from Huffman Tx!
    Just wanted to tell you keep up the excellent job!

    ReplyDelete
  27. What's up to every one, it's in fact a good for me to go to see this site, it consists
    of precious Information.

    ReplyDelete
  28. Hi there! I'm at work surfing around your blog from my new apple iphone!
    Just wanted to say I love reading your blog and look forward to all
    your posts! Carry on the outstanding work!

    ReplyDelete
  29. I'm writing to let you know of the beneficial
    experience my cousin's girl found going through your blog.
    She figured out a good number of details, which included how it is like to have a wonderful teaching heart to get folks without problems grasp several hard to do
    subject matter. You really exceeded my desires. Thanks for presenting those priceless, healthy, informative and also cool tips about the topic to Evelyn.

    ReplyDelete
  30. Wonderful goods from you, man. I have understand your stuff previous to and
    you are just too magnificent. I actually like
    what you have acquired here, certainly like what you are saying and the way in which you say it.
    You make it entertaining and you still take care of to keep it sensible.

    I can't wait to read much more from you. This is really a wonderful web site.

    ReplyDelete
  31. Awesome! Its genuinely awesome piece of writing, I have got much clear idea about from this piece of writing.

    ReplyDelete
  32. I wanted to thank you for this excellent read!!
    I definitely loved every bit of it. I have got you book
    marked to check out new stuff you post?

    ReplyDelete
  33. Hello, just wanted to say, I loved this blog post.
    It was practical. Keep on posting!

    ReplyDelete
  34. Hey there! Do you use Twitter? I'd like to follow you if that would be
    okay. I'm absolutely enjoying your blog and look forward to new updates.

    ReplyDelete
  35. Enjoyed reading this, very good stuff, thank you.

    ReplyDelete
  36. Simply want to say your article is as astonishing. The clearness in your
    post is simply excellent and i could assume you're an expert on this subject.
    Fine with your permission allow me to grab your RSS feed to keep
    up to date with forthcoming post. Thanks a million and please continue the gratifying work.

    ReplyDelete
  37. As a Newbie, I am constantly exploring online for articles that can help
    me. Thank you

    ReplyDelete
  38. Very nice post. I just stumbled upon your weblog and wanted to say that I have really enjoyed surfing around your blog
    posts. After all I will be subscribing to your rss feed and I hope you
    write again very soon!

    ReplyDelete
  39. Its like you read my mind! You appear to grasp so much about
    this, like you wrote the e-book in it or something.

    I feel that you simply can do with some percent to drive the message home a bit, however other than that, that is magnificent blog.

    A great read. I'll definitely be back.

    ReplyDelete
  40. Hello There. I found your weblog the use of msn. That is a really well written article.
    I'll be sure to bookmark it and come back to learn extra of your helpful information. Thank you for the post.

    I will definitely comeback.

    ReplyDelete
  41. hi!,I really like your writing so much! percentage we communicate more approximately your post on AOL?
    I need an expert on this area to resolve my problem.

    Maybe that is you! Having a look forward to see you.

    ReplyDelete
  42. Some genuinely prize blog posts on this website, saved to bookmarks.

    ReplyDelete
  43. I got what you mean,saved to fav, very decent internet site.

    ReplyDelete
  44. Hi, yup this article is truly nice and I have learned lot of things from it regarding blogging.

    thanks.

    ReplyDelete
  45. I would like to thank you for the efforts you have put in writing
    this site. I am hoping the same high-grade website post from you
    in the upcoming as well. In fact your creative writing skills has inspired me to get my own site now.
    Really the blogging is spreading its wings rapidly.
    Your write up is a good example of it.

    ReplyDelete
  46. Hoàn tất việc đăng ký tài khoản Win2888.

    ReplyDelete
  47. I like this article. I was searching on the search engine and found your blog. I get more knowledge and I read a lot of interesting content here. keep doing it. test and tag services perth

    ReplyDelete

WAZIPOINT:
Thank you very much to visit and valuable comments on this blog post. Keep in touch for next and new article. Share your friends and well-wisher, share your idea to worldwide.