The 40 A rated current (In) and 380-415 V AC operational voltage (Ue) size it for three-phase sub-distribution boards feeding mixed loads. The Type A-SI (Super Immunised) classification means it handles pulsed DC fault currents from electronics (Type A capability) plus enhanced immunity against nuisance tripping from transient surges or high-frequency leakage — useful on lines with VFDs, UPS systems, or switching power supplies. The 1500 A making/breaking capacity (Idm/Im) covers the switching duty for the leakage path itself. Clip it onto a DIN rail (8 module pitches wide at 9 mm each, so 72 mm) and torque the terminals to 3.5 N·m; wire stripping length is 14 mm for top or bottom connection.
This RCCB mounts via clip-on to a standard DIN rail inside a distribution board or modular enclosure.