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Regulation stating a type AC RCD can not be upstream from a type A RCD

Alan B

Hi

I found an EV charger today with built in type A RCD + RDC-DD connected to a type AC RCD in the consumer unit, the AC RCD is also protecting 3 other circuits including sockets. I know this is incorrect because the type AC RCD could be blinded by DC currents, but I am struggling to find a regulation to reference when providing information to the customer?

Thanks

Alan

Parents
  • 0

    There was a thread on here recently about boiler manufacturers stating in MIs that type A RCD should be used. I queried this with a manufacturer, asking why they used products with DC leakage, the DC component magnitude and why they were introducing something onto the market which was potentially dangerous, given that most installations in the UK had AC types fitted. Here is their slightly unsatisfactory reply

    "The design of the pump used in our (and all other manufacturers of ErP appliances) boilers requires a type A or type B RCD as defined by the pump manufacturer.

    The design of these pumps is to ensure compliance with ErP regulations. The leakage current is <3.5mA. Type AC RCD’s are now very limited in their use and are suitable for resistive, capacitive and inductive loads without any electronic components.

    Most modern electrical equipment used within properties now comes under the requirements for a Type A RCD including power supplies for Class 2 equipment, washing machines, LED lighting, induction hobs etc."

  • 0 in reply to OlympusMons

    As you say OM, the manufacturers don't understand either, it is as though there is some push to type A, B or F RCDs. Now I have deliberately opened this can of worms, because I actually care about what is in the regulations. I see a problem (and recently there was another one about IT supplies) because it appears that the regulation chain has no persons who can actually analyse the proposals coming from Europe. I wonder why this is? Thanks Mike for making your points, I completely agree, and the reason must be either snag shifting or money. I don't recognise the term ErP. Is this a European thing? So now a pump manufacturer has DC? leakage of 3.5mA or less but wants a type A? Please explain why that might be.

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  • 0 in reply to OlympusMons

    As you say OM, the manufacturers don't understand either, it is as though there is some push to type A, B or F RCDs. Now I have deliberately opened this can of worms, because I actually care about what is in the regulations. I see a problem (and recently there was another one about IT supplies) because it appears that the regulation chain has no persons who can actually analyse the proposals coming from Europe. I wonder why this is? Thanks Mike for making your points, I completely agree, and the reason must be either snag shifting or money. I don't recognise the term ErP. Is this a European thing? So now a pump manufacturer has DC? leakage of 3.5mA or less but wants a type A? Please explain why that might be.

Children
  • 0 in reply to David Stone

    CYA syndrome or perhaps to "monetarise the situation" David ? 

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