CU Installation, Step by Step

[AliRaZoR]

funniest forum's members

Hi

Could any one teach me, how to design and install a CU?
How to select RCD,MCB(and connection)?

thanks in advance.​

 

[topquark]

As you're from an electronic engineering background you can appreciate that changing a CU is akin to developing a PCB with corresponding components. It requires the skills to test and upgrade the earthing and bonding. It also requires the knowledge to select an appropriate type of circuit protection device for each circuit, whilst ensuring compliance with the appropriate British Standards.

Whilst one could describe the physical process of installation, it's the inspection and corresponding testing, that ensures compliance with BS7671, that's more important. This will require the purchase of high cost test equipment and the necessary training to use them correctly.

Whilst I'm certain that you would not have a problem with the electrical theory involved, there is a lot more experience required than just understanding the theory (although it does help a lot).

The advice you're being given, although in jest, is serious.

 

[AliRaZoR]

Look fella, what you are asking advice about takes us electricians a long time to learn. There isn't a book on how to do a c/u change step by step, you have to learn every aspect of the electrical installations before you can attempt it. Fare enough its not rocket science but your playing with things that can kill you or others, your not playing with lego! Phone a local spark who can do this for you and keep your home safe.

I do not want to change my home CU or other people CU, i just want to learn something. i have some information about home wiring, MCB selection, but i only asked for the RCD wiring and the way that is connected in CU,...

 

[Big n Daft]

stop acting like JERK,
Never went near it matronmg_smile:

 

[Paul.M]

I do not want to change my home CU or other people CU, i just want to learn something. i have some information about home wiring, MCB selection, but i only asked for the RCD wiring and the way that is connected in CU,...

Sorry I don't believe you. A little knowledge is a dangerous thing, and that's why I hope no one gives you the answer to your question. Why would you want to learn about this subject if you are not going to change a c/u? Why have you already got information about mcb selection? Sorry but I'm out.

 

[1shortcircuit]

Some of these books may help you with certain areas :thumbsup

 

[AliRaZoR]

Some of these books may help you with certain areas :thumbsup

thanks for reply, I have downloaded all of those book.

 

[AliRaZoR]

Sorry I don't believe you. A little knowledge is a dangerous thing, and that's why I hope no one gives you the answer to your question. Why would you want to learn about this subject if you are not going to change a c/u? Why have you already got information about mcb selection? Sorry but I'm out.

MCB selection is not a big deal, but RCD selection is very important as i know.why do you think i wanna become electrician? this is not my job.my goal is only LEARNING.
anyway thanks for help.

 

[malcolmsanford]

Ok Ali we will play nicely, you have just made a statement that MCB selection is not a big deal, but it is RCD protection that is important.

Can you elaborate on that as I think as an electrician it is the other way round, but would be interested in why you think this

 

[Paul.M]

I've just seen your "edited" first post deleting the full post and changing the title to "forums funniest members". REPORTED. Good luck with your studies, you'll need it with an attitude like that. Why did it take you 5 pages to tell us that your studying to become an electrician? Why can't you find in all those books that you have downloaded, about rcd's? What makes you think that mcbs are not as important? Do you know the difference in-between a rcd and a mcb?

 

[telectrix]

dotted line.... CUT HERE!. is that what the razor is for?

 

[AliRaZoR]

I've just seen your "edited" first post deleting the full post and changing the title to "forums funniest members". REPORTED. Good luck with your studies, you'll need it with an attitude like that. Why did it take you 5 pages to tell us that your studying to become an electrician? Why can't you find in all those books that you have downloaded, about rcd's? What makes you think that mcbs are not as important? Do you know the difference in-between a rcd and a mcb?

MCB is for overload protection and short circuit
RCD : must respond as soon as there is leakage current, Z should be in correct range

I changed the title because you are making fun with my post

give respect to get respect

 

[Paul.M]

Where and what course are you studying?

 

[malcolmsanford]

You are on the correct path if perhaps not going in quite the right direction.

An RCD is looked upon as a miracle aid for the electrical industry where it is just an aid to correct design. Through out the BS 7671-2008 section and Regulations advise the electrician on RCd protection such as additional protection in the home 30mA and fire safey not exceeding 300mA so it is just the testing that is complicated.

MCBs are a little more complicated as they supply both overload and Fault protection. To design a system that incorporate just MCB protection alone you have to calculate Volt Drop, Rating Factors, length of runs and cable impedance, etc etc and this is something that can only be taught.

This is why we are taking your posts with that proverbial "pinch of salt", as it is impossible to have a generic book that will cover this subject

 

[Paul.M]

I changed the title because you are making fun with my postgive respect to get respect

Respect is what you earn and not given away. If your straight with us we will be straight with you and then you may start earning my respect.

 

[AliRaZoR]

Where and what course are you studying?

if you do not get angry, as a electronic engineer i have to have some information about home wiring.

 

[AliRaZoR]

Respect is what you earn and not given away. If your straight with us we will be straight with you and then you may start earning my respect.

what do you mean "If your straight with us"? the main goal of forum is to help people not making fun of them. i respect to every member in this forum and use thanks button for their help.

 

[AliRaZoR]

You are on the correct path if perhaps not going in quite the right direction.

An RCD is looked upon as a miracle aid for the electrical industry where it is just an aid to correct design. Through out the BS 7671-2008 section and Regulations advise the electrician on RCd protection such as additional protection in the home 30mA and fire safey not exceeding 300mA so it is just the testing that is complicated.

MCBs are a little more complicated as they supply both overload and Fault protection. To design a system that incorporate just MCB protection alone you have to calculate Volt Drop, Rating Factors, length of runs and cable impedance, etc etc and this is something that can only be taught.

This is why we are taking your posts with that proverbial "pinch of salt", as it is impossible to have a generic book that will cover this subject

what do you mean by fault protection? could you explain a little more.

 

[truckster]

:rolleyes4:

 

[malcolmsanford]

http://wiki.diyfaq.org.uk/index.php?title=Electrical_Glossary

Under F

 

[Paul.M]

RCD - DIYWiki.

 

[telectrix]

what do you mean by fault protection? could you explain a little more.

fault protection, to put it simply, is when you get a fault, e.g. a short circuit, the MCB ( fault protection device) trips out, thus cutting off the supply when it goes bang, before the cables are damaged by the excess current flow.

 

[Spudnik]

I havent had time to read the whole thread, but for now, I think we are done here.