The FI block (RCU) is for customer-side assembly with automatic circuit breakers from the S200, S300 series. The resulting FI/LS combinations (RCBOs) offer personal and material protection as well as protection against electrically ignited fires in accordance with DIN VDE 0100-410 and DIN VDE 0100-530. They guarantee protection of 1P+N, 2P, 3P, 3P+N or 4P circuits against overload and short-circuit currents, protection against sinusoidal alternating currents and pulsating currents with a smooth DC residual current component of up to 6 mA against earth. As well as fault protection (protection against indirect contact), additional protection (with I¿n = 30 mA) and fire protection (with I¿n = 300 mA). They meet the product standard IEC/EN 61009 Appendix G. Areas of application are household, commercial and industrial applications. The extensive range of accessories offers you everything you need for your installation tasks. Optimum compromise between safety and operational continuity thanks to the interference immunity with surge current resistance (surge current form 8/20 µs) = 3,000 A against unwanted tripping and 10 ms short-time delay. The rated switching capacity when installing MCB S200 6 kA, S200 M 10 kA, S300 P 25 kA.