The Siemens SENTRON 5SV3617-6KK01 is a 2-pole residual current circuit breaker (RCCB) in the 5SV3 short-time delayed design, rated 80 A at 40 °C and 230/400 V AC. The short-time delayed switching (often called 'selective' or 'S-type' in other brands) means it withstands brief surge currents — rated here at 3 kA — without tripping, so nuisance trips from lightning or capacitor-switching transients don't take a feeder offline while downstream MCBs clear a fault first.
Snaps onto a DIN rail (REG profile), occupies 2 width units (36 mm), and accepts conductors from 0.75 mm² up to 35 mm² — solid or stranded. The 70 mm installation depth matches standard SENTRON modular-device spacing, so it sits flush in a distribution board alongside MCBs and surge arrestors. The IP20 rating applies only when the distribution board is installed with connected conductors — typical for enclosed panelboards, not for open racks.
Thermal derating — the real-world current
Above that, the continuous current drops: 77.87 A at 45 °C, 74.77 A at 50 °C, 70.26 A at 55 °C, 64.32 A at 60 °C, 56.96 A at 65 °C, and 48.19 A at 70 °C. The I²t value of 110 000 A²s is the let-through energy the device can withstand, relevant for coordination with upstream breakers.
Overvoltage category III — suitable for fixed-installation distribution boards, not just downstream equipment. Finger and back-of-hand safe per the shock-protection classification. The part is assigned function F under DIN EN 61346-2 and DIN EN 81346-2, which is the standard functional designation for residual-current protective devices in industrial schematics. Silicon-free construction matters for applications where silicone outgassing can contaminate contacts or optics (e.g., automotive paint lines or clean-room panels).