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High protective conductor currents - Deletion of 543.7.1.204

543.7.1.204 - the one about duplicate c.p.c.s needing to be 'terminated independently of each other' - has gone.

Does anyone understand the thinking behind this? It seems a bit odd to me.

Given that (in my experience) more problems occur at terminals rather than along cable runs, if we need the c.p.c.s to be duplicated, it seems like a bit of a flaw that one single loose connection can make them both useless simultaneously. I can see that in some instances (e.g. a terminal on a socket on a ring) that losing a single terminal carries a limited immediate risk (as the leakage current from a single socket should be small and all other sockets are still connected to a c.p.c.) but in other instances - say the connection of both c.p.c.s to the earth bar in a DB - that single fault could be very significant.

   - Andy.

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  • Yes it's gone, a sad day for me as I sat on the IEE panel that produced those regulations and that one was my suggestion.  It is the only thing I could claim to have actually got into the regulations.  I contributed to other regulations but so did everybody else on the panel. So my lifes work is now in the trash can.

    Regards

    Geoff Blackwell

  • We calls it our Blackwell Inheritance 

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