What size earth on a TT ?

[Risteard]

It's 2.5mm IIRC

If mechanically protected.

 

[Nightmare1308]

Not sure why discussing the minimum size is crucial, when the Guide is to have 200ohms or less(NICEIC)?
To me bigger the cable = Less resistance ?
I would always like to provide the lowest ohmic value wouldn't you agree ?

 

[Leesparkykent]

Not sure why discussing the minimum size is crucial, when the Guide is to have 200ohms or less(NICEIC)?
To me bigger the cable = Less resistance ?
I would always like to provide the lowest ohmic value wouldn't you agree ?[/QUOTE

Your 1st point of call would surely be to try to get a better value on your earth electrode/s not just up the CSA of the main earthing conductor which is hardly going to make a difference in this instance.

 

[123]

Not sure why discussing the minimum size is crucial, when the Guide is to have 200ohms or less(NICEIC)?
To me bigger the cable = Less resistance ?
I would always like to provide the lowest ohmic value wouldn't you agree ?

200Ohms is BS7671 BGB
100 Ohms is NIC EIC

 

[telectrix]

200Ohms is BS7671 BGB
100 Ohms is NIC EIC
and 1.0Ω is eng54.

corrected for you there.

 

[Leesparkykent]

corrected for you there.

That should be <1.0 ohms lol

 

[telectrix]

thought we were talking max. values.:juggle2:

 

[baldsparkies]

He would not get along well with me. I allow three hours out of my day for my CPS assessment and I provide a local job to look at. All Paperwork out and ready. I Will be having my 10th one this year. If there was any personal preference nonsense (outside BS7671)from him I would end the visit right there and switch CPS. All they are to me is a vehicle to enable me to notify jobs, nothing more.

And that sir, is hitting the proverbial nail on the head.
Year on year we are asked, "why don't you go approved contractor" and year on year we say, because we don't bleeding need or want to.
Its a blatant status myth, that they want us to buy into because it benefits them not us.
All our commercial contracts are based on our personal experience, knowledge, and formal qualifications.
Jib cards take precedence with most of the contract and facility managers we deal with.
I tell the assessors this, and you can hear there rear ends tighten up.
We don't need there approval, or imaginary status thank you very much.
They provide a cost effective way to sign off part P compliant works, when dealing with the joke of a minefield called domestic electrics.
Sorry lads, end of rant.

 

[baldsparkies]

200Ohms is BS7671 BGB
100 Ohms is NIC EIC

Yet another situation that the jokers should have sorted years ago, I think its called communication !!

 

[uksparks]

he got very iffy with us one year whilst on a site visit after he noticed that we had stopped installing flying earth leads to back boxes , even though I could name the scheme staff member who had advised us not to , only the month before !

I had this with the NICEIC bloke, one said don't put them on, and gave me a few reasons as to why, so I stopped as I thought yeah ok, then the next bloke ripped me apart and j said yes but the other bloke said not to do it, this is also the case with s couple of other things, you are right though, depending who you ask you get a different response.

 

[shanky887614]

I had this with the NICEIC bloke, one said don't put them on, and gave me a few reasons as to why, so I stopped as I thought yeah ok, then the next bloke ripped me apart and j said yes but the other bloke said not to do it, this is also the case with s couple of other things, you are right though, depending who you ask you get a different response.

the fronts are earthed by the pins so why doesnt it need a flying lead?

they shouldn't be removed if power is still on or not competent(electrically skilled)

 

[Engineer54]

Originally Posted by JD6400
he got very iffy with us one year whilst on a site visit after he noticed that we had stopped installing flying earth leads to back boxes , even though I could name the scheme staff member who had advised us not to , only the month before !

Well right or wrong, we still install flying leads to all back boxes as a matter of course for all power type accessories!! Can't really remember not doing so to be honest!!

 

[JD6400]

Well right or wrong, we still install flying leads to all back boxes as a matter of course for all power type accessories!! Can't really remember not doing so to be honest!!

I did not over like the idea at the time , but it did save a fair bit of time . Not that it matters now as we went back to doing so anyway .

 

[GEOFF S]

Look at the definition of an exposed conductive part and a extraneous condutive part, will the backbox satisfy the definition?

Cheers

 

[shanky887614]

Look at the definition of an exposed conductive part and a extraneous condutive part, will the backbox satisfy the definition?

Cheers

if its surface it might