16757 RCCB 4P 63A 300mA B type - Can this RCCB be used on 230/400Vac 2 phase and N wiring system?

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Yes the RCCB is compliant with 2P+N 230/400V networks.
You must connect neutral terminals (N) and the last two phases (5-6 & 7-8, for test button function)

RCCB Wiring for 2 phase and N wiring systems