Sizing and selectivity
The Siemens SENTRON 5SY5132-7 is a 1-pole miniature circuit breaker with C-curve tripping characteristic, rated 32 A at AC and delivering a 10 kA breaking capacity per EN 60898. The 32 A rating at 35 °C derates to 30.46 A at 40 °C and 27.14 A at 60 °C, so if this breaker lands in a warm cabinet the continuous load must be trimmed accordingly.
At 18 mm width (1 modular unit) it occupies a single slot in the distribution board, leaving room for additional poles or auxiliary devices in the same row. Depth of 76 mm with 70 mm installation depth means it fits flush in standard enclosures without protruding past the DIN rail. IP20 with connected conductors — suitable for dry indoor panels but not washdown areas.
That -40 °C floor makes it usable in unheated shelters or cold storage environments; the 75 °C ceiling matches typical panel interior temperatures under full load.