The A9F57116 is a 1-pole Acti9 IKQ miniature circuit breaker rated 16 A with a C-curve (magnetic trip 5...10 x In), designed for AC networks at 240 V AC, 50/60 Hz. Its 10 kA Icn breaking capacity at 240 V (EN 60898-1) means it can safely interrupt a fault current up to 10,000 A without welding contacts or cascading upstream — sized for residential and light commercial final circuits where the prospective short-circuit current is known. The thermal-magnetic trip unit handles the long-time overload (thermal bimetal) and short-circuit (solenoid) in one package; no earth-leakage protection inside, so if you need GFCI, add a separate RCCB or RCBO downstream.
The 18 mm width (1 module pitch) and plug-on mounting to a standard DIN rail mean it snaps into any distribution board or sub-panel without extra hardware. Depth of 78.5 mm and height of 85 mm leave clearance for front-cover trim and cable bending radius. The bottom terminal accepts 1…25 mm² rigid or 1…16 mm² flexible wire; strip 14 mm and torque to 2 N·m. The toggle control and trip indicator give local status at a glance — no need to meter the load side to see if it tripped.