If you are unsure about the reason for the 2 CPC's try reading this thread & if you can make it past the argumentative quoting, there might be a gem or 2 in there.
Methinks that thread needs surmising as its a damn hard read
The additional 4.0mm² CPC IS required, as this is a branch from a high integrity radial circuit, and the high integrity needs to be extended to the new branch.
Using an additional 4.0mm² singles is one way of ensuring this.
I'm not sure you have enough experience of special installations to be working on this circuit.
If you are unsure about the reason for the 2 CPC's try reading this thread & if you can make it past the argumentative quoting, there might be a gem or 2 in there.
Methinks that thread needs surmising as its a damn hard read
Although, it is not really relevant to this thread as our bickering is about ring circuits. The OPs question is about a radial circuit, which I think we are all agreed on.
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