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Changing MCBs to RCBOs is it notifiable under part P

Synapse

Now retired I am no longer a member of a competent persons scream, I was full scope member of NICEIC, 2391 qualified etc;   I can still hold a screw driver and press the buttons on my MFT when I can remember where I put them down.  

In the lovely house we built to retire in the 21 way consumer unit is full,  having had a lot of twinkly LEDs wiped out in the recent thunder storm , I think urge protection would be a good idea.

In order to free up the slots occupied by two RCDs and have space for the urge protector by simply changing the MCBs to RCBOs.  Is this notifiable under part P.

 I have done some other recent electrical changes and our local building control who are absolutely super relieved me of around £100 for the pleasure of fitting some 16A industrial sockets in my workshop because the work was indeed notifiable.    I would prefer not to have to pay another £100. 

  

  • +1

    Are you changing the circuit characteristics or its protection? - arguably a 32A MCB plus RCD is the same protection as a 32A RCBO... so probably not, and I presume it is not in a bathroom and you are not actually changing the CU,

    Note that even if it was notifiable,  I presume you are not going to report yourself !!

    In your own house I'd suggest that if you can do the work safely and verify it to your satisfaction, hold off on notifying stuff until you move out of the place and then if your conscience bites get it all inspected at once!

    There is so much stuff just happening in properties up and down the land and not being notified, even by folk working as businesses who ought to know better, that no one is really going to worry about the exact details unless it is actually dangerous. So, the real question is,  can you do the work safely and verify it properly ?

    Mike.

  • 0

    i would say it is possibly notifiable. Not because you are changing the characteristics of the circuits, they were already RCD protected and they would be like for like replacements rating-wise, assuming you don't find nasties like discontinuous ring conductors. But because the SPD would need an OCPD to protect it. If using one of the RCBOs for overcurrent protection, to comply with 534.4.7 it must have immunity to surge currents of at least 3kA 8/20, so this should be checked with the RCBO manufacturer. So notifiable if a new SPD circuit is created.

    Edit; Also you would presumably be using mostly Type A RCBOs, instead if the existing Type AC (if they are?) pair, so technically the characteristics of the circuits would be changed.

  • +1

    Synapse

    I think "urge protection" is something you might buy from Boots or maybe the pharmacist in your local supermarket.

    How did you surge get in ? Do you have an overhead supply? Do you have a Lightening Protection System  (LPS)?

    If you have an underground supply then you can cut the tails to you consumer unit and put a Wylex REC 2 switch in with a built in Type 2 SPD. It gives you surge protection  for your consumer unit and a means of isolation if you want to work on your consumer unit when you get a smart meter, that is what I did.

    If you have an overhead supply and/ or an LPS then you are going to need a combined Type 1 and Type 2 SPD. Install this in an enclosure a close as possible to your consumer unit and move the circuit breakers around so you can connect the SPD in the 1st way after the main switch. 

  • +1

    Crack on and say nothing - Your proposals only amount to adding additional protection to existing circuits, albeit changing the existing circuit protection characteristics in a positive way.

    I would get on with it and not bother building control in the slightest.

    Least said, soonest mended, not to mention it's a lot cheaper too!

  • +1

    Fitting of a new CU is notifiable. Installation of a new circuit is notifiable. I don't think that changing bits in a CU is notifiable, nor is the addition of sockets of whatever variety.

  • 0 in reply to John Peckham

    Many thanks John,  although retired I need to do some more homework. We live in a rural area; our supply in overhead.

  • 0 in reply to OlympusMons

    17th ed was my last bible and my understanding of SPD and AFFD in domestic properties is far from complete some  CPD is missing.   The SPD devices sold in new consumer units do not have over current protection they sit next to the isolator.   So a bit confused when you say OCPD is needed ?

  • 0

    Many thanks for the input everybody - really helpful

  • 0 in reply to Synapse

    Some SPDs are required to be protected by an external OCPD; others have built-in protection - typically in the form of a one-shot soldered internal link.

  • 0

    Regarding sockets. If you have an existing socket circuit A then add some more sockets B then remove sockets A then it is not notifiable. but if you first remove A then add B it is notifiable. Just a thought LOL. 

    Did Part P ever do what it was intended to do? Ok more folk have test gear nowadays (some of them might actually know how to use it) . Most of the myths are still the same myths as they always were but nowadays we have a few brand new myths to enthral us too

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