On 27/05/2019 10:48, The Natural Philosopher wrote:
On 27/05/2019 09:47, Tricky Dicky wrote:
if I go for RCBOs in the garage CU and stick with am MCB in the main
CU, does that MCB need to be outside of any RCD protected group or can
it be RCD protected.

My (limited) understanding is that it wouldnt NEED to be RCD protected
but there is no requirement that it is *not* so protected.

In this particular case there is, since the OP does not want to lose
discrimination. If you have regular RCDs/RCBOs (i.e. non time delayed
ones) at both head end and final circuit end, then you can't rely on one
tripping in preference to the other.


--
Cheers,

John.

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