The A9N21023: The 6 A rated current (In) sets the continuous load this MCB can carry without tripping — sized for a branch circuit drawing up to 6 A. The 4500 A Icn is the rated short-circuit capacity per the domestic-standard EN/IEC 60898-1; the 6 kA Icu is the ultimate breaking capacity per the industrial-standard IEC 60947-2, giving headroom for higher fault-current installations. The 1P+N configuration switches the phase and disconnects the neutral — common for single-phase final subcircuits in distribution boards.
At 18 mm wide (2 x 9 mm pitches), it fits standard modular enclosures. Tunnel-type terminals accept 0.33–10 mm² flexible or 0.75–16 mm² rigid wire; strip length 13 mm, tighten to 2 N·m. IP20 finger-safe front. Complies with EN/IEC 60898-1 and EN/IEC 60947-2, pollution degree 3, overvoltage category IV. Separate earth-leakage block can be added alongside.