EIC or MWC

Scenario:

Existing lighting circuits with fluorescent luminaires upgraded to LED equivalents.

Circuit breaker changing type and/or rating.

Contractor has provided an MWC covering the works.

All looks good, but because the circuit protective device is not strictly a like for like change, should they have actually provided an EIC?

  • As long as all the relevant test results are recorded, I don't think it really matters which certificate is used or even just a piece of paper with hand-written details.

    Presumably if a MEIWC does not have all the required details needed for a given job then the job was not a minor work.

    I don't know what like-for-like (which never appears in the regulations) has to do with it.

    If connecting, for example, a new shower or cooker I would have (retired now) tested the circuit; none of which had been altered; to make sure everything was as it should be. 

    Incidentally - why was the MEIWC introduced in the first place? 

    I note the definition in BS7671 -

    Minor works. Additions and alterations to an installation that do not extend to the provision of a new circuit.

    is obviously ridiculously inadequate, i.e. wrong, as according to that the replacement of a consumer unit can have just a MEIWC.

  • Minor works only. You’re not adding a circuit or doing any significant alternations that would require anything more

  • Apologies for jumping on the back of this thread, but I have recently had a similar experience:

    After a contractor replaced a distribution board for a larger DB along with new circuit protection devices, to cater for additional circuits, they provided an EIC but only for the new circuits. After querying if they had recorded any testing on the existing circuits such as R1&R2, continuity, RCBO disconnection times etc... I received the following response:

    The tests listed are not basic verification; they are full electrical tests that we were unable to carry out. The tests listed are dead tests that would have required all of the equipment, computers, access control, etc disconnecting from the circuits prior to testing otherwise damage to the electronic components would have occurred. 

           All of the existing circuits had been tested on the 05/11/21 and are not due to be retested until the 05/11/26. We have utilised the existing sub main cable and MCCB fed from the electrical intake room and therefore there was no alteration to the Ze reading at the existing DB. No alterations to the circuits have been carried out with the exception of being reconnected to the new distribution board. Our test engineer did carry out a visual inspection prior to the distribution board changeover and also carried out a visual inspection after the mains change over to ensure that all circuits were connected and correct, the functional test of each new RCBO was also carried out (Operation Of Test Button) and he also tested the tripping times of RCBOs (at the DB only), these were all within the required tripping times. These were not recorded on the test sheets and were carried out for his own piece of mind to confirm that the RCBOs were working correctly. Due to the installation of the RCBOs to all outgoing circuits the installation is deemed safer than the previous installation due to the additional protection.

          We were only given 1 day to carry out the installation of the New DB and the full testing of the existing circuits would have required at least another full days work for 2 electricians. Due to the fact that we had the existing test certificates on the final circuit wiring that indicated that all cables were OK, and the fact that we did not joint or extend any cables, and the fact that we were making the installation safer than the previous installation due to the inclusion of additional protection to the circuits, we feel that we have achieved a safer installation and have done everything possible within the time restraints given and as detailed in the specification. 

    I thought I would have been issued with a fully populated EIC, with limitations listed surrounding testing of the existing circuits, but in this instance I haven't received anything...

    Looking at previous responses to the thread (in particular the response given by AMK detailing the NICEIC guidance) It seems that replacing circuit protective devices would at least merit a MWC per new device?

  • Interesting - I can see both sides of the argument, but what they did seems reasonable to me. Had the final circuits not been in date, it would have been a different matter.

  • Humm. Personally (and this is just my personal opinion) re-terminating existing cables into a new DB constitutes work that has has the potential to introduce new problems - insulation may be been damaged on sharp edges, conductors (especially c.p.c.s) broken or imperfectly terminated, or even L-N reversal on the output of the RCBO. Hopefully good workmanship should minimise the chances of such things happening, and diligent visual inspection may pick up some problems. Some risk remains though I feel, so I would be happier if some inspection and testing had been done to verify a.f.a.r.p. that no new faults had been introduced. I wouldn't necessarily expect a full I&T on the entire circuit - an R2 and polarity tests to the first accessory and L+N to PE insulation test (perhaps even at a reduced voltage) to verify the reading is no worse than before (even if it's <1M) might well suffice.Of course the results want writing down in some form if you wish to prove at a later date that things were done sensibly.  

    Of course negotiating the time to do a job properly is a matter of contract (along with any consequent limitations) but such things should be sorted out before rather than after..

       - Andy.

  • The change of the consumer unit and the connection to it of the existing circuits have to be verified as safe to be put back into service, through the testing and the recording of results. You should have a schedule of test results with the installation, covering all of the circuits that have been connected to the new consumer unit

  • https://www.electricalsafetyfirst.org.uk/professional-resources/best-practice-guides/#g1

    if you have a look at part 7 of this guide it tells you the testing that they should’ve carried out and recorded on your schedule of test results

  • Just to provide further information if anyone has a similar query in the future, please see the information provided by the NICEIC:

    The Certsure / NICEIC Technical Helpline provides general information and guidance for compliance with the British Standard BS 7671, the Requirements for Electrical Installations, and matters concerning electrical safety within electrical installations designed, constructed, inspected, and tested to BS 7671.

    We are unable to provide dedicated design services or comment on financial, legal, or contractual matters relating to an enquiry. With the information provided we offer the following general guidance: -

    BS 7671:2018+A2:2022 contains requirements for new electrical installations and alterations/additions to existing installations. A replacement distribution board would be classed as an alteration to an existing installation, as such this work (The replacement of the DB) would need to be verified and certificated in accordance with Chapter 64 of BS 7671. This would not apply to the existing circuits.

    Electrical Safety First has produced guidance on changing consumer units within their publication Best Practice Guide 1 (BPG1). Although this is aimed at domestic installations, the information and guidance can equally be adopted within commercial installations.

    Section 7 of BPG1 covers the inspection and testing that is recommended following a consumer unit change, it should be remembered that this information is guidance and does not form part of BS 7671.

    We would recommend that you discuss these recommendations with the contractor concerned.

    best-practice-guide-1-issue-5.pdf (electricalsafetyfirst.org.uk)

    For confirmation, I responded:

    For my piece of mind, just to further confirm as per your notes below, the replacement of the DB and circuit protection is classified as an alteration to the installation and therefore, the existing final circuits do not require testing or verification prior to being reenergised.

    Subsequently, by providing an electrical installation certificate for the new circuits, which we can then append to the original EICR results for the existing circuits (basically storing the two attached documents on site), the electrical contractor will meet the requirements of BS7671:

    641.5: For an addition or alteration to an existing installation, it shall be verified that the addition or alteration complies with BS 7671 and does not impair the safety of the existing installation.

    641.7: On completion of the verification, according to Regulations 641.1 to 641.6, a certificate shall be prepared.

    And received a further response:

    The replacement of a distribution board and protective devices would be classed as an alteration to an existing electrical installation, the installation of new circuits would be classed as an addition to an existing electrical installation. Both of these activities would require certification, these could be recorded on the same Electrical Installation Certificate (EIC), with both the boxes for Alteration and Addition being ticked. The NICEIC EIC differs slightly from the Model form in BS 7671, in that it contains a tick box for ‘Replacement of a distribution board’. Therefore, on a NICEIC EIC ‘Replacement of a distribution board’ and ‘An addition’ would also be acceptable.

    With regards to the existing final circuits, the installer of the replacement DB is not responsible for these circuits, but good practice would be to carry out sufficient testing to ensure that any new protective devices for this circuits would function correctly under fault conditions.

    The EIC for the new work and any previous certification for the existing circuits should be retained for future reference.

    Hope that's helpful!