RCBO for final-circuit protection with combined overcurrent and residual current
Rated 20 A at 30 °C, it protects final circuits against overload, short-circuit, and earth faults in one unit — saving a DIN-rail position versus separate MCB + RCCB. The 30 mA AC-type residual current detection handles sinusoidal earth faults, the most common type in residential and light commercial installations. The higher 15 kA rating under IEC 60947-2 provides additional fault-current headroom for industrial distribution boards where prospective short-circuit currents may exceed 6 kA.
Thermal derating and mounting flexibility
Rated current is temperature-dependent: 20 A at 30 °C, derating to 18.8 A at 40 °C, 17.4 A at 50 °C, 16.2 A at 60 °C, and 14.6 A at 70 °C. In a crowded enclosure with elevated ambient, apply the derated value — the 40 °C figure (18.8 A) is the practical design limit for most panel environments. The 2 MW (36 mm) width matches standard SENTRON modular spacing; depth is 77 mm, installation depth 70 mm. Halogen-free and silicon-free construction suits environments sensitive to outgassing, such as clean rooms or telecom shelters.