Selective (short-time delayed) design lets it ride through transient earth faults and coordinate with downstream RCDs, so only the faulted branch trips and the rest of the distribution board stays live.
At higher enclosure temperatures the unit derates: 58.6 A at 40 °C, 58.59 A at 45 °C, 56.7 A at 50 °C, 54.81 A at 55 °C, 53.55 A at 60 °C, 52.29 A at 65 °C, and 50.4 A at 70 °C. The 300 mA rated tripping fault current is a high-threshold setting, typical for selective (S-type) RCDs. It avoids nuisance tripping from leakage currents in long cable runs or equipment with filters, while still providing earth-fault protection. The surge current resistance of 5 kA means it withstands lightning-induced or switching transients without damage. Rated insulation voltage is 460 V, overvoltage category III, so it's suitable for fixed-installation distribution boards fed from the mains supply. Depth is 70 mm, matching the 5SY MCB it couples with.
Snaps onto DIN rail (REG) in any mounting position. The RC unit is designed as a companion for the 5SY series MCB — it clips alongside or feeds from the same busbar. IP20 with connected conductors in an installed distribution board; the enclosure itself provides the finger-safe coverage. Silicon-free construction (product feature) matters for applications where silicone outgassing can contaminate contacts or optics — automotive paint shops or clean-room adjacent panels, for instance.