It protects a single outgoing circuit against overload, short-circuit, and earth leakage in one DIN-rail slot. The 20 A rating at 50 °C and B-curve trip characteristic make it a standard choice for general-purpose socket circuits and lighting in commercial and light-industrial panels where inrush currents are low. The 30 mA earth-leakage sensitivity covers personnel protection per IEC 61009-1.
For a 20 A RCBO on a TN earthing system, 10 kA provides adequate fault clearance on most distribution boards fed by a transformer of up to about 630 kVA, assuming typical cable impedances. The limitation class 3 (energy-limiting) means it lets through less let-through energy than a class 1 or 2 device, which helps with downstream coordination and reduces arc-flash risk on the outgoing circuit.
Clip-on mounting to DIN rail, 18 mm width (2 x 9 mm pitches), 77.5 mm depth, 110 mm height. IP20 applies to the front face when installed in an open panel.