Rated for 40 A, B-curve, 10 kA — what that means on the panel
The Siemens 5SY5140-6 is a 1-pole SENTRON miniature circuit breaker rated 40 A at 400 V AC with a B tripping characteristic and a 10 kA breaking capacity per EN 60898. The 10 kA SCCR at 400 V means it safely interrupts faults up to that level without cascading upstream; the DC side is rated 10 kA per EN 60898-2 and 15 kA per IEC 60947-2 at 220 V. A single modular width (18 mm) on DIN rail, so it fits standard panels with 1 MW of rail space.
Depth is 76 mm (installation depth 70 mm), width 18 mm (1 MW), height 90 mm.
Operating temperature range -40 °C to 75 °C, with humidity derating: 95 % RH up to 55 °C, 55 % RH up to 70 °C, 35 % RH up to 75 °C.