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Unfused spur.

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Hello All,


Could an unfused R.C.D. protected spur, from a complient ring final circuit, supplying a single outdoor socket via 1.5mm2 6242Y cable of max. length 300mm through a brick wall from an indoor socket outlet be considered compliant?


Z.
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  • 0
    It is satisfactory Andy, 1 mm2 and 1kA is safe for 13 milliseconds to 70 degrees. A B32 will easily break that. This ring must have a PFC of a few hundred amps max, and the final temperature as long as it is less than about 500C, may damage things but will not fail. Old rings may have 1mm cpcs, and these do not fail, now you know why! The RCD will probably trip too in typically 20ms at such a current. It is very safe. Z can do a loop PSCC to Earth test at the new socket, the result will be interesting.
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  • 0
    It is satisfactory Andy, 1 mm2 and 1kA is safe for 13 milliseconds to 70 degrees. A B32 will easily break that. This ring must have a PFC of a few hundred amps max, and the final temperature as long as it is less than about 500C, may damage things but will not fail. Old rings may have 1mm cpcs, and these do not fail, now you know why! The RCD will probably trip too in typically 20ms at such a current. It is very safe. Z can do a loop PSCC to Earth test at the new socket, the result will be interesting.
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