The Schneider Electric A9N19855 is a 4-pole Acti9 C120L miniature circuit breaker rated 100 A at 30 °C with a D curve — magnetic trip kicks in at 10 to 14 times In per GB/T 10963.1, and 12 x In ±20 % per GB/T 14048.2. That D curve is your go-to for motor and transformer inrush: it holds through the starting surge and clears a hard fault. Breaking capacity is 15 kA Icn/Icu at 400 V AC 50/60 Hz, dual-rated to both EN/IEC 60898-1 and EN/IEC 60947-2. That dual standard means you can use it in a distribution board (60898-1) or an industrial panel (60947-2) without swapping parts.
DIN-rail fit and wire-up
Clip-on mount to standard DIN rail (35 mm per EN 60715). 12 module pitches at 9 mm each — that's 108 mm of rail space, so plan your enclosure fill accordingly. Tunnel terminals accept 1 to 50 mm² rigid (no ferrule) or 1.5 to 35 mm² flexible with/without ferrule.