TT System

[EddieB]

I've just changed a surface double socket to a flush one and tested it the reading I got was 2.5k ohms!!!
I checked the earth wire to the electrode and it was a 6mm ,the electrode itself needed cleaning which I did with a file and replaced the earth clamp this improved the reading to 26 ohms. The main switch is a 100ma RCD I assume that I need to incorporate either a 30ma rcbo on the sockets or change the board to a split load board with 2 x 30ma RCD's and a 100anp mains switch is thjis correct?

 

[DurhamSparky]

if you just did a like for like replacement then you dont need to RCD any thing...!

but yes a TT system or any domestic system for that matter should ideally have all circuits RCD protected by a 30MA device if you wish to bring itup to speed with 17th edition

you can do away with the 100Ma device if you installed a split load 2x30ma board.

 

[EddieB]

Yeah I thought as much, once I found the extremely high earth path and had to do something about it I feel I'm obliged to update the board, the main earth wire was mechanically unprotected I think that will need to be up sized from a 6mm to a 16mm. Thanks for your help DurhamSparky

 

[DurhamSparky]

is it your box then??

 

[EddieB]

No not my box, but I'm not happy in leaving the board without 30ma cover

 

[ezzzekiel]

you could add a rcd protected socket or fcu as its a minor works

 

[DurhamSparky]

you could add a rcd protected socket or fcu as its a minor works

that could get expensive!! lol...!! especially since he been fitting flush mounted ones lol..!!

eddieB the 100ma device in at present will be doing the job perfectly fine for last --- amount of years!

but i do liek your attitude to bring up to speed with 17th

 

[ezzzekiel]

he only changed one socket although he neednt do anything additional as it was only maintenance,

you may not be happy leaving it without 30ma cover, but will the customer be happy with the additional costs for simply changing a socket front?

advise the best you can, however you have fulfilled your role correctly

 

[dichroic]

Where an addition or alteration (whether temporary or permanent) is to be made to an installation, the relevant requirements of BS 7671 have to be met such that both the addition or alteration is safe, and the safety of the existing installation is not impaired.

Regulation 131.8

‘No addition or alteration, temporary or permanent, shall be made to an existing installation, unless it has been ascertained that the rating and the condition of any existing equipment, including that of the distributor, will be adequate for the altered circumstances. Furthermore, the earthing and bonding arrangements, if necessary for the protective measure applied for the safety of the addition or alteration, shall be adequate’.

Regards

Dichroic