The Schneider Electric A9D50220 is an Acti9 iC60 RCBO — a combined overcurrent and residual-current device in a 2-pole, 20 A, C-curve configuration. It integrates thermal-magnetic overcurrent protection (C-curve, magnetic trip 5–10 x In) with 300 mA earth-leakage detection in one 36 mm wide DIN-rail module, saving a slot over separate MCB+RCCB. Rated 20 A at 50 Hz AC, it carries a 10 kA Icn breaking capacity per EN/IEC 61009-2-1 and a 15 kA Icu per EN/IEC 60947-2 at 220–240 V. The 300 mA residual sensitivity is set for equipment protection rather than personnel shock — typical for distribution outgoers feeding fixed machinery, lighting, or socket circuits where nuisance tripping from leakage on long cable runs needs to be avoided.
Clip-on DIN rail mounting, 4 x 9 mm pole pitches (36 mm wide). Tunnel terminals accept 1–35 mm² rigid or 1–25 mm² flexible cable; strip 12 mm and torque to 2 N·m. The 9 mm connection pitch between poles matches standard busbar comb sets for the Acti9 range. IP40 in a distribution enclosure, IP20 bare. Local signalling shows ON, OFF, and fault trip status via the toggle position — no need to meter the load side to confirm a trip.