The A9F05140 is a 40 A, 1-pole miniature circuit breaker from the Schneider Acti9 iC60N family, built for distribution panels where you need a D-curve trip characteristic. On a 230 V AC lighting or general-purpose circuit a C curve would nuisance-trip; the D curve gives you the headroom without oversizing the breaker. Breaking capacity is where this part earns its keep in an industrial panel. At 12-60 V AC it's rated 36 kA Icu per EN/IEC 60947-2; at 220-240 V AC it's still 10 kA Icu. It also carries a 6000 A Icn rating at 230 V AC under the domestic-standard EN/IEC 60898-1, so it's dual-certified for both industrial and residential applications — useful if your BOM crosses both worlds. The thermal-magnetic trip unit is non-interchangeable, which is the norm for MCBs in this class — you spec the rating at order time and it stays. Isolation capability is confirmed to both standards, meaning you can safely use the toggle as a visible disconnect for downstream work.
Mounting and wiring — what to tell the panel builder
That's a generous wire range for a 40 A breaker — you can land a 6 mm² feed and still have room for a 16 mm² downstream tap in the same terminal. The toggle gives you a clear visual trip indicator — when the breaker trips, the handle settles in a mid-position that's easy to spot during a walk-down.