It is a type B device, meaning it detects smooth DC residual currents as well as AC and pulsed DC — essential for installations with variable-speed drives, UPS systems, or photovoltaic inverters that can generate fault currents a standard AC/type A RCCB would miss. Rated at 25 A continuous at 400 V AC (50/60 Hz) with a 30 mA trip threshold, this unit is sized for general-purpose branch-circuit protection where earth leakage must be caught early. The short-time delayed design (selective/s-type) coordinates with downstream RCCBs, preventing nuisance tripping on transient leakage from connected equipment. The 3 kA surge current resistance handles lightning-induced transients without false trips.
Installation depth is 70 mm, fitting most enclosure depths.
Thermal derating — plan for the panel temperature
The 25 A rating holds up to 45 °C ambient. Above that, the continuous current must be reduced: 24 A at 50 °C, 23 A at 55 °C, 22 A at 60 °C, 21 A at 65 °C, and 20 A at 70 °C. If the distribution board runs warm (adjacent to drives or transformers), size the upstream protection accordingly or allow ventilation.