What it is and what it does
The Siemens SENTRON 5SY4440-8 is a 4-pole miniature circuit breaker with D-curve tripping, designed for overcurrent protection in industrial control panels and mechanical engineering installations. It meets IEC/EN 60898-1 for 10 kA and IEC/EN 60947-2 for 15 kA breaking capacity, with a maximum operating voltage of 440 V AC (single- or multi-phase).
Mounting and panel fit
The breaker occupies 4 modular width units (72 mm) on a standard DIN rail, with a depth of 76 mm and an installation depth of 70 mm. It can be mounted in any position and is sealable, with combined top and bottom terminals for wiring flexibility. The IP20 rating applies with connected conductors.