The Schneider Electric A9N21360 is a Prodis DT40N miniature circuit breaker, 1 A rated current, 1P+N configuration, curve C thermal-magnetic trip. It clips onto a DIN rail for panel integration and carries a breaking capacity of 6000 A Icn at 230 V AC per EN/IEC 60898-1 and 10 kA Icu at 230...240 V AC per IEC 60947-2.
The 1 A rating suits low-current branch circuits — think control transformers, signal power supplies, or pilot devices. The dual breaking capacity (6 kA Icn for distribution, 10 kA Icu for industrial) gives you selectivity headroom: the Icu figure is the ultimate short-circuit withstand, while Icn is the rated service capacity. Both standards (EN/IEC 60898-1 for residential and IEC 60947-2 for industrial) are listed, so this breaker is accepted in either context.
Integration notes
Clip-on mounting on a DIN rail, 18 mm wide (2 x 9 mm pitches). Tunnel-type terminals accept 0.33...10 mm² flexible or 0.75...16 mm² rigid on both upstream and downstream sides. IP20 finger-safe enclosure, pollution degree 3, overvoltage category IV. Earth-leakage protection requires a separate block.