On page 24 of GN8 I see there's a table about the type of soil and resistivity which I will look at, just saying, I don't need a response to this.
Looking on page 28, Table 2.3, it looks at suitable materials for linking the rods together. Does anyone know where I would find the recommended CSA of the cable linking them or would you just use the same as the main conductor going back to the MET?
This thread has shown that some supposedly 'competent' people are just not at all competent to install some very basic equipment in peoples houses (or anywhere else for that matter.) 6mm earth? 300mA RCD? Not quite sure about some things.
How about not sure about a lot of things?
How can anyone quote for such a job when they do not have the relevant knowledge to do it properly?
Of course, all is good, as the customers are protected as the person doing the work has been 'assessed' by their Governing Body. (laughs all the way to the bank!)
Shut up will you.
To be fair, if someone said a 6mm earthing conductor in a TT install was too small, then went on to ask if a 300mA upfront RCD was required, then, surely they are not competent to do this work.
It is not that they are 'not worthy', but really, why try to make yourself look a fool, when you've got a green book in front of you to answer anything you don't quite know about?
It is in BS7671, and these facts should be pretty much known off by heart for such basic queries. If someone hasnt done a TT before, then maybe they should read up about it, learn a little more, then ask further queries once they have gained this knowledge.
However, such basic questions should be known by anyone calling themselves an electrician.
This shows how low the Industry standards are now, that someone is 'allowed' by their Governing Body to do such work, and the Customer is reassured that the Contractor is assessed, and passed to do such work, is, frankly, laughable, when it is clear they are not competent.
The 6mm conductor, I am not saying this has never worked and doesn't provide an adequate connection etc, what I was suggesting is that it is less than the minimum CSA permitted by BS7671, see table 54.7 on page 162 of the BGB. It clearly states that the if the CSA of the line conductor is between 16mm and 35mm the CSA of the earthing conductor needs to be 16mm which is why I said it's too small as the CSA of the line conductor is 25mm ok.
The point of the 300mA RCD upfront, I said I was under the impression it was required, and I made it very clear I had not done a TT instal before and was after some guidance. So get down of your horse and stop being rude.
Also if you install an S-Type RCD you will not be fulfilling any requirements for additional protection. Additional protection is afforded by an RCD with a rated residual current of not more than 30mA and must disconnect within 40mS at 5xRated residual current. An S-Type RCD will not comply, see 531.2.1
On the other hand though, i think you would be a fool not providing an upfront S-type RCD device. it may not comply as additional protection, but will back up a failed downstream 30mA RCD. The reason I said can I put a 300mA there instead, is because neither a 100mA not a 300mA will save your life in terms of a fault and cutting out before you get belted, but both will meet the requirements of 532.1 for protection against the risk of fire.
So we have established that the upfront RCD is to be put there for protection against fire in the event of a fault, I and others have agreed this, so why are you taking the pee out of me for saying 300mA?? At least it wont trip out on a 5x fault on the board. Ok you could go for a S-type, but there's nothing wrong with a 300mA RCD upfront.
The main points are not aimed at you, - you said:
"It happens all to often on this forum when some members post a question that certain members think they have a right to try and belittle and make the posting member feel they are not competent or worthy to be on the forum"
Really, such queries should be told that they are not competent. Would they say to the Customer "Well, I havent done this before, and dont really know much about it, so I'll take a guess, then get the answer on the internet"
If you want to promote a quality trade, which adheres to standards, then surely such people should be told to learn more before they practice their trade on a customer?
I'm not taking a guess at it at all, I am looking into it and reading the relevant books, IE. BS7671 and GN8 etc to see what I need, I will then call someone who has kindly offered their advice and discuss it with them, and when I am happy with what needs to be done I will then go back to the customer and say yes or no.
You are trying to make out that I am a novice and don't know what I'm doing and out my depth.
Extec chill out mate, there is no place for insulting regular members and getting personal.
We are constantly told by Admin to be nice to new members, but that can be extremely hard when you are throwing insults at everyone so enough is enough now.
Well said, some people on here can be quite rude. There's one thing making a cheeky comment, but then there's people who are just rude and out for the kill.
