The Type A-SI (Super Immunised) designation means the earth-leakage detection circuit is hardened against nuisance tripping from high-frequency harmonics, pulsed DC waveforms, and transient surges common on variable-speed drives, UPS systems, and LED lighting — loads that would trip a standard Type A device. The 30 mA sensitivity provides supplementary protection against electric shock for personnel, while the C-curve magnetic trip (5–10 x In) handles moderate inrush from motor and lighting circuits without nuisance trips. Rated current is 25 A at 30 °C, and the breaking capacity is 6000 A Icn at 230 V AC, conforming to EN/IEC 61009.
The tunnel-type terminals accept 1…16 mm² rigid or 1…10 mm² flexible with ferrule; strip length is 15 mm and tightening torque is 2 N·m. For a panel OEM or MRO planner, this means the RCBO fits a standard 4-module cutout and terminates with standard screw-clamp wiring.