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Can you replace just the RCD, instead of whole consumer unit?

Former Community Member
Former Community Member
My apartment failed it's EICR due to the electrician not being able to trip the RCD in the required time.  I am told that the RCD cannot be replaced and a new metal consumer unit must be installed at a quote of £1180.  The apartment was built in 2003 and seems overly wasteful to ditch the whole unit, however I am not an electrician so would welcome some guidance please before I commit to this remedial action.


This is the RCD currently fitted:
5760S | MK 63 A RCD Switch, Trip Sensitivity 30mA | RS Components (rs-online.com)


It appears it worked within spec for above 30mA, but failed for below, if that helps with whether the whole consumer unit must be replaced.  See report.
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  • Former Community Member
    0 Former Community Member
    Chris Pearson:
    LB2:

    I have spoken with another electrician to get a second opinion, he said that the test results seem strange, as the trip responded in 30ms above 30mA as it should, but marked faulty because it didn't trip below 30mA but electrician 2 seems to think that's by design and shouldn't trip with currents lower than 30mA.

     


    I took this to mean that if the RCD is a 30 mA one (or 10 mA) it is tested at 5 times the value, but if it is > 30 mA (100 mA, 300 mA, etc.) it is tested at 1 times the value.


    It need not trip below 30 mA, but should do so rapidly at 150 mA. On the face of it, it has not tripped at all.


     




    Interesting, many thanks.  Apologies if I'm missing something, but as there is only one RCD, shouldn't only one of those boxes be filled?  ie there's one '30mA or below' RCD so the 'Above 30mA' shouldn't have a value in it?


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  • Former Community Member
    0 Former Community Member
    Chris Pearson:
    LB2:

    I have spoken with another electrician to get a second opinion, he said that the test results seem strange, as the trip responded in 30ms above 30mA as it should, but marked faulty because it didn't trip below 30mA but electrician 2 seems to think that's by design and shouldn't trip with currents lower than 30mA.

     


    I took this to mean that if the RCD is a 30 mA one (or 10 mA) it is tested at 5 times the value, but if it is > 30 mA (100 mA, 300 mA, etc.) it is tested at 1 times the value.


    It need not trip below 30 mA, but should do so rapidly at 150 mA. On the face of it, it has not tripped at all.


     




    Interesting, many thanks.  Apologies if I'm missing something, but as there is only one RCD, shouldn't only one of those boxes be filled?  ie there's one '30mA or below' RCD so the 'Above 30mA' shouldn't have a value in it?


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