Friendly advice needed please . . . .

[vickery1971]

Hello All, Please go easy on me as I am relatively new to the profession. I have my annual surveillance visit and plan to offer up a Distribution board (being done tomorrow) and a Garage rewire (left part done as assessor requested so I can do dead tests), They are both at the same property.
The house, a 60’s bungalow has old wire fuses, no RCD but has a pool and Jacuzzi bath! . . . . it may prove to be interesting!

I just wanted to say what I plan to do so I can get some opinions on the best way to do things . . . . Here goes!

First change the main CU for a 17[SUP]th[/SUP] dual RCD board with one non RCD’d way in which I will put a 40A MCB from which I will run 6mm 3 core SWA using spare core as CPC (25m clipped direct VD 5.84 with a load of 32A)
Metal Wylex garage CU with one 32A ring, 6A lighting, 16A radial to pool. (ring in garage as the assessor likes me testing his ring!)

My experience with sub boards on SWA is limited but I plan to gland and bond the SWA each end. Q1: When I test for my Zdb do I do it with the glands linked or just using the 6m earth in the SWA? Q2: If there happens to be a metal water pipe in the garage am I right that I have to run a 10mm earth from the main DB to DB2 (it’s tns) and bond the water?

Thanks for any advice you can give.

Ian

 

[vickery1971]

Ah, thats interesting, people always slate TT'ing garages but never explain why. And i didint realise you need permission to export the suppliers earth . . . .you learn somthing new every day!
I always carry a few rods so i can stick one in, belt and braces i suppose.
And is there any reason you shouldnt connect the earthing arrangements both ends? (I usually only connect one end i just noticed a lot of people on garage posts saying do both)

Thanks for the advice

 

[onions1066]

Yes because you don't want an earth fault within the garage installation affecting the consumer rcd, keep the earthing separate, gland it consumer end and earth the armouring that end, In my opinion , good luck with assessor.

 

[Plonker 3]

By rights you should really install a rod for the garage, you shouldn't really export the suppliers earth out of the equipotential zone without there written permission, people will moan regarding this but that's the deal. That could be one of the things your assessor looks for because I remember a few years ago during an assessment I was asked this exact question. And you shouldn't connect the two earthing arrangements together via the armourings.

What complete and uttet tosh. Find me a rule or regulation that says exporting a equipotential zone is not allowed.

 

[shocking_eg]

Soo many rumours regarding exporting suppliers earths it's ridiculous !!

Your 'extending' not exporting your equipotential zone so nothing wrong with that.

Why would you opt for a crappy TT when you have a much lower earthing system already !

 

[vickery1971]

Hmmmmm thanks for the input chaps . . . . .

So in your opinion, would what I plan to do in my OP be adequite?

Im probably going to start another debate but im just trying to get this job as near to 100% right as i can, after all, how can those of us with fewer years under our belts learn if we are too scared to ask the learned ones among us.

Ohhhhhh its snowing again

 

[MDJ]

What was the question again!!

 

[Plonker 3]

What was the question again!!

Can I export a equipotential zone mg_smile:

 

[MDJ]

Gasp not this again

 

[vickery1971]

Aw shucks . . . . . and i only wanted some friendly advice

Maybe we should change the forum name to 'fight club'

 

[Spoon]

Maybe we should change the forum name to 'fight club'

There would be too many rules for me to remember if we did that.

 

[Rockingit]

What complete and uttet tosh. Find me a rule or regulation that says exporting a equipotential zone is not allowed.

Well done Dill - I was just going to say that's a load of Bo11ocks, but you were slightly more polite. I think Mr Onions needs a little more time back in the soil.

 

[Rockingit]

And to the OP - By the sounds of it I think you'll be just fine, carry on.

 

[44ALLAN]

Does that mean I have to disconnect the earth from my garden lights and sockets and bang a couple of rods in?

 

[telectrix]

use the 3rd core of the SWA as cpc and the armour as a bonding conductor. or is it vice versa. i can never remember.

 

[onions1066]

What complete and uttet tosh. Find me a rule or regulation that says exporting a equipotential zone is not allowed.

Again dillb spouting off about shat you don't know, you get permission off the supplier and I will apologise. You go rough it in.