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Test certification & changes to supply characteristics

Looking for some guidance please, I am working on a construction site with a large temporary accommodation block due to be occupied asap. Due to design issues the HV/ LV supply has been delayed, to work around this a generator will be utilised as a short term solution. 
This means testing & inspection will be completed via the genset and certs issued, when the new substation is completed the generator will be disconnected and sub-mains will be connected to the permanent LV supply. 
This raises a question regarding re-test, in my experience usually best practice would be a full re-test, but some on the project are suggesting only the sub-mains will require re-testing. 
To me this would probably come down to the designer signing the test cert and what they are prepared to accept, if only re-testing the sub-mains  I would think the final circuits Zs/ Pfc would have to be calculated as the previous test results/certs from the generator would be invalid due to the change of supply characteristics right?

So can anyone offer advice as to the options and is there anything in BS7671 regs that would be relevant to this situation, it’s also worth considering that if a EIC is issued for the generator can there be another issued for the LV supply? Is it possible to issue more than 1 EIC or  update the original or would be a condition report? 
I’ve come across this situation before and it always seems to be a contentious subject with lots of different opinions, sorry for the long winded post, but would really appreciate some professional opinions on this, thanks Pray 

Parents
  • The sub-mains, are these distribution circuits actually flexible cables from the generators to the accommodation blocks?

  • Armoured cables to the MDU’s I think, this part of the installation is also not complete yet. The accommodation is pre-wired modular, the question is will the results from the generator supply for the final circuits in the accommodation still be valid after the generator is gone and the MDU’s are connected to the network. I don’t see how the initial certificate can be valid, the reactance of the genset will be different from the network characteristics and there are 2 separate designs for each 

  • The modular units will have there own certificates showing dead tests. Once connected to whatever supply, ADS needs to be addressed whether TT or TNS.

    I would expect a report showing live tests following connection to whatever the source supply is. Probably an EICR would be fine to show the ADS compliance coupled with the dead test certificates.

Reply
  • The modular units will have there own certificates showing dead tests. Once connected to whatever supply, ADS needs to be addressed whether TT or TNS.

    I would expect a report showing live tests following connection to whatever the source supply is. Probably an EICR would be fine to show the ADS compliance coupled with the dead test certificates.

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