Posting a message to the forum will remove the above advertisement

Discuss When to install metal consumer units in the Electrical Forum area at ElectrciansForums.co.uk.

Please make sure you checkout our forum sponsors, many do discounts for members and, they keep the forum free to use.
  1. alex kane
    Offline

    alex kane Active EF Member

    Hi Everyone

    I am aware that we now have to install metal consumer units in domestic premises now but at what point should we swap a plastic board over to a metal one?

    The reason I ask is I've been to plenty of jobs where there is a plastic CU with no RCD protection. Ideally I would swap the main switch for an RCD but should I also be swapping over the whole CU for a metal one?

    What work/ at what point do you say to the customer "you need a new CU" besides when the job is to install a new one obviously? I know I could write a note on my EIC but personally I'd rather not have to do that.
     
  2. Flanders
    Offline

    Flanders Regular EF Member

    Location:
    Tamworth
    Not sure I would ever just change a main switch with a RCD Unless required for a TT supply.
    The only reason that I could see a domestic installation needing upgrading to RCD protection to make the installation safe would be for socket outlet liable to be used outdoors and you could fit an RCBO or RCD sockets for that.
     
    • Like Like x 1
  3. Murdoch
    Online

    Murdoch Electrician's Arms

    Location:
    Woking
    Do you think swapping a main switch for an RCD complies with the regs?
     
  4. Midwest
    Online

    Midwest Electrician's Arms

    Location:
    Oxfordshire
    Don't thing the spirit of 421.1.201 requires any replacement of plastic to metal, regardless of how much the inners you replace. That would just be maintenance.

    If you replaced the CU because of lack of replacement parts, then that would be the time to apply the reg.

    Someone recently posted about moving a CU, i.e. to one side a few inches. That was a lively debate :)
     
    • Like Like x 2
  5. static zap
    Offline

    static zap Regular EF Member

    Location:
    west midlands
    (RCD - for Main switch )...

    The disadvantage is being in the dark , actually !
     
  6. alex kane
    Offline

    alex kane Active EF Member

    RCCB's that meet BS EN 61008 are rated for isolation so I don't see the problem? I know on a big installation this wouldn't be ideal but say on a CU with four circuits.
     
  7. Ian1981
    Online

    Ian1981 Electrician's Arms

    Location:
    North east
    In what context do you require a rcd main switch to replace a main switch isolator?
    I.e. What job are you undertaking that requires it?
     
  8. Murdoch
    Online

    Murdoch Electrician's Arms

    Location:
    Woking
    ^^ best you review 314 in the BYB
     
  9. Risteard
    Offline

    Risteard Electrician's Arms

    Location:
    Derry, Ireland
    Business Name:
    Walsh Electrical Services
    I would suggest that it can depending on the circumstances. It's certainly not expressly forbidden. A risk assessment would determine whether inconvenience caused was excessive or presented any danger. As someone else mentioned maybe there are only a handful of circuits fed from the DB with other DBs present. Otherwise we would outlaw all instances of using an RCCB to protect more than one circuit which would be a nonsense!
     
    • Like Like x 1
  10. Murdoch
    Online

    Murdoch Electrician's Arms

    Location:
    Woking
    ^^ I only raised this as lots of people don't seem to realise that this reg even exists... there are, of course lots of RCBO options .....
     
  11. alex kane
    Offline

    alex kane Active EF Member

    The reason I ask this question is because most customers won't pay for RCBO's even when I've explained it's the best option because of the cost. If I'm to do work in their house I need to ensure it's RCD protected to cover my back. Swapping the main switch for an RCD is the quickest/ most cost effective way to do this.

    I suppose installing one RCBO for the circuit I've worked on would suffice but it would be better to ensure the whole property has RCD protection. This scenario is where I wasn't sure whether I would have to change the CU to a metal one.

    Which reg specifically says you cannot use an RCD as a main switch?
     
  12. Murdoch
    Online

    Murdoch Electrician's Arms

    Location:
    Woking
    Corrected that for you

    You are obviously new to the game ... a RCBO is more than adequate AND then you only need to test / inspect your circuit - install an upfront RCD means you need to test the entire installation too.

    As for changing a CU to AMD3 for a new circuit or circuit change - this is NOT the case, and anyone saying this is not being honest.
     
    • Dumb Dumb x 1
  13. Ian1981
    Online

    Ian1981 Electrician's Arms

    Location:
    North east
    If you are working on multiple circuits which, by the work that has been undertaken require rcd protection ( installed extra sockets, installed new wiring into a bathroom) then if no rcd protection exists to the installation, the client should be notified of what the new works will entail and what requirements/ changes are needed to the installation/consumer unit before work is undertaken.
    Individual rcbo s are an option if the existing consumer unit can accommodate.
    The consumer unit if changed to allow the multiple circuits worked on rcd protection would then require to be constructed of a non-combustible material ( ferrous)
    Installing an upfront rcd protecting the whole installation is generally regarded as poor practice and offers no division of circuits for safety purposes think the regulation has been quoted 314 etc.
    One faulty circuit may cause the full installation to disconnect which is a nuisance if anything and highly inconvenient.
    If it was an acceptable method the dual rcd consumer units would be irrelevant.
    Hope this helps.
     
    Last edited: Apr 19, 2017
  14. alex kane
    Offline

    alex kane Active EF Member

    I understand it's not always good practice but getting people to pay for a new board/ RCBO's isn't always easy. On small boards with 4 circuits or less I don't see this being too much of a problem. A split load 20 way board would have 10 circuits on 1 RCD each. I don't hear people moaning about that.

    I always tell my customers if they need an upgrade. Testing the whole installation is a minor inconvenience to me when we're talking about a safety issue.

    All I wanted to know was whether installing an RCD as a main switch was possible and whether the board would require changing.

    I think it's obvious from Murdoch's comments he doesn't know a much as he lets on and just likes slamming others comments.

    You're never too old to learn
     
  15. Murdoch
    Online

    Murdoch Electrician's Arms

    Location:
    Woking
    Matey ... if you have a house with a 4 way CU or a 20 way CU, adding a single up front RCD will deliver the same result when a fault occurs - EVERYTHING will switch off...

    A RCBO will cost less that a RCD and testing ALL the other circuits...... what is there not to understand?
     
Loading...
Similar Threads - install metal consumer Forum Date
Lack of space to install a new metal consumer unit - advice Industrial Electrician Talk Mar 10, 2016
Installing a secondary consumer unit in the garage?? Looking for Domestic Electricians? Today at 8:36 AM
Quick Question Old 3 Phase Install Electrical Forum Sunday at 7:54 AM
Sizing power cables part installed in ducts Industrial Electrician Talk Thursday at 9:02 AM
Pete's Videos All yoy ever needed to know about installing an electric cooker Electrical Forum Aug 8, 2017
Profestional alarm install, mains supply 0.5mm2 flex into back of a socket Electrical Wiring, Theories and Regulations Aug 6, 2017

Share This Page

  • Electricians Directory Post a Domestic Job Post a Commercial Job