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Ring continuity test high reading

Former Community Member
Former Community Member

I recently tested a kitchen ring main circuit during an EICR. I removed a socket in the kitchen for inspection and tested ring cont. The L-L and N-N was both 0.24 ohms. But when testing the ring continuity of the kitchen skts from the consumer unit the L-L is 0.24ohms and the N-N is 0.57ohms. I would check more of the sockets in the kitchen but someone has grouted them in place which is going to be messy to remove.

Is there something simple I am missing regarding the higher continuity when tested at the CU? Id expect it to be the same at each point unless interconnected but then all conductors would be similar. Any help is greatly appreciated. Thank you

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    Ok, it must be that at the socket you tested the L-L terminal was adding some excess resistance, perhaps because the screw was loose. The problem cannot be elsewhere, because the wires when removed from the socket tested fine.

    Now the problem is why you asked this question. You should have enough knowledge of circuit theory to know that there cannot be any other explanation, however good you think the socket L connection was. Remember Sherlock Holmes, "Once everything else is eliminated (CU loop test), that which remains must be the answer however unlikely (Poor L-L connection in the socket). (Paraphrased slightly to match the question). If the same problem happens with the Earth, the answer is much more complex, because there may well be parallel paths present, supplementary bonding, or any number of similar things. 

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  • 0

    Ok, it must be that at the socket you tested the L-L terminal was adding some excess resistance, perhaps because the screw was loose. The problem cannot be elsewhere, because the wires when removed from the socket tested fine.

    Now the problem is why you asked this question. You should have enough knowledge of circuit theory to know that there cannot be any other explanation, however good you think the socket L connection was. Remember Sherlock Holmes, "Once everything else is eliminated (CU loop test), that which remains must be the answer however unlikely (Poor L-L connection in the socket). (Paraphrased slightly to match the question). If the same problem happens with the Earth, the answer is much more complex, because there may well be parallel paths present, supplementary bonding, or any number of similar things. 

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