Similar to yourself I don't have edition 2 of the regs yet so some things may have been changed. I'm also not the best person to give opinions on domestic certification because I never do domestic work of any kind.
Originally Posted by
hartdev@hotmail.com
1. No earth electrode resistance test done and of course the fact that there was no earth spike at all.
It is a TN-C-S supply as usual in these parts.
His reply was that the regulations state that for existing installations the "secondary earthing mat/spike" on the clients property is not compulsory on a TN-C-S supply.
The certificate is also passed under the "for an installation existing before this publication of sans10142"
Yeah, from the photo he obviously didn't do an Ra test on the earth electrode but, regardless if the regs state it's required, if it was installed and if it's still connected then it should be part of the CoC. The regs state the absolute minimum requirement but sometimes a higher standard may be required, especially when it comes to earthing arrangements. Is it plain TN C S or is it PME or PNB? Effectiveness of earthing is highly prone to seasonal changes and it may have also been the opinion of a previous electrician that a local earth rod was required for some reason, hence my stance that if it's there it should be fully functional and subject to testing and inspection during certification.
Removing or ignoring deteriorating earth electrodes is extremely bad practice IMHO and I wouldn't be taking blase statements about 'not compulsory' or 'before publication of regs' as an excuse. If it was installed at one time then it has to be considered that there was a good reason and I think the onus to prove it's no longer required would then fall on anyone who removes it or fails to maintain it or claims it's unnecessary. The minimum motivation I'd be satisfied with is full earth impedance tests and earth fault disconnect times calculation to prove adequacy of existing earthing, also confirmation there's no special location or medical location requirements, also confirmation there's no alternative supply requirements (generator/UPS etc) and a risk assessment taking consideration of likely seasonal ground conductivity changes and local lightning requirements. Customer requirements could also play a part ie effective operation of surge arrestors for protection of IT equipment etc if they're installed.
Originally Posted by
hartdev@hotmail.com
2.There were no insulation resistance tests done
This he informed me was also not required for an existing installation.
The property changed hands so a full CoC was required. To my knowledge insulation tests should have been included...
Code:
6.6.1.22 The insulation-resistance test on wiring and components shall
be performed in accordance with 8.7.8.
Code:
8.7.8.2 The insulation resistance, measured as follows, shall be at least
1,0 MΩ:
Amdt 8 allowed for a half assed exception but I don't see why it would apply....
Code:
8.7.8
NOTE 2 In the case of existing installations where the power may not be switched
off from certain circuits in order to carry out this test, the fact that the circuits are
subject to the supply voltage can be regarded as evident that the insulation
resistance is compliant. Amdt 8
Originally Posted by
hartdev@hotmail.com
3. section 4 no. 15 "Is the position of a readily accessible earthing terminal..."
This he had indicated "YES" but there was definitely none installed.
He informed me that this was no longer necessary as per new regulations
Yeah, I hear edition 2 changed the requirement for the accessible earthing terminal
Originally Posted by
hartdev@hotmail.com
4. Lastly at the WC1 box there was 2 orange toggle circuit breakers (d curve), 50amp and 30amp. With a seoerate prepaid meter in the flatlet and main home.
He had signed the flatlet off as a sub DB instead of having 2 separate certificates which he agreed is how it should have been done, but I would like to know if we are correct in that assumption in your opinion?
I'd only class the flat as a sub-DB if it was fed from the main DB. If the flat supply is completely independent from the main house DB then you have two main DB's which should have been tested as separate installations.
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