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Three Phase RCD & MCB Wiring?

Nano Brewery
Please could somebody advise on the most cost effective procedure of wiring up RCDs & MCBs on a DIN Rail for independent circuit protection.  Tried Googling to no joy.  Plenty of Single Phase advice, images, videos.  If using 4 Pole MCBs & RCDs, would I be correct in assuming that similar to single phase, it's just a case of Busbar-ing the MCB Lives to the RCD Lives and taking the RCD to Neutral Bar?


Have seen diagrams (like below) where the Incoming L1, L2, L3 get split to separate DP MCBs, RCDs and SP MCBs for each phase.  Seems like a bit of a faff and a pricey option (3x DP MCBs + 3x RCDs + 3x SP MCBs) per circuit.


I have 3x Three Phase Circuits (13A, 40A, 48A) that I wish to protect independently with RCDs.


Thanks in advance!  Dan.

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    Note By "Cost effective" the initial cost of One only RCD per phase then to all the MCBs on that phase will be the cheapest initial outlay. But RCBO on each circuit will mean only that one faulty circuit will trip an leave the others capable of running. A 4pole (3P +N) RCCB can not be used on single p[ole circuits as it will trip unless all three phases are drawing exactly the same currents
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    Note By "Cost effective" the initial cost of One only RCD per phase then to all the MCBs on that phase will be the cheapest initial outlay. But RCBO on each circuit will mean only that one faulty circuit will trip an leave the others capable of running. A 4pole (3P +N) RCCB can not be used on single p[ole circuits as it will trip unless all three phases are drawing exactly the same currents
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