Part identity and key ratings
The Siemens 5SL6140-6RC is a SENTRON miniature circuit breaker rated 40 A, 1-pole, with a B tripping characteristic and a breaking capacity of 7.5 kA per EN 60898. That B curve means the magnetic trip operates at 3 to 5 times rated current — standard for residential and light commercial final circuits where inrush from lighting or small appliances is modest. The 7.5 kA rating at 415 V AC tells you this breaker can safely interrupt fault currents up to that level without welding contacts or cascading upstream, which is the figure that governs coordination with the upstream protective device. The single-pole design occupies one modular width unit (18 mm) on a DIN rail, with a depth of 76 mm and an installation depth of 70 mm. It accepts supply voltage up to 250 V AC single-phase or 440 V AC multi-phase, and is rated for 50/60 Hz networks. The IP20 protection class (with connected conductors) is standard for enclosed panel mounting — not for wet or outdoor locations.
Installation and integration
Snap-on mounting to a 35 mm DIN rail, any position. The 18 mm width (1 MWU) fits standard panel layouts. Sealable design allows tamper-proofing after commissioning. The breaker accepts supplementary devices (auxiliary switches, shunt trips, undervoltage releases) for remote status or emergency-off integration. Terminal design accepts copper conductors typical for 40 A branch circuits; strip length and torque values follow the manufacturer's installation instructions.
Environmental and compliance
Rated for ambient temperatures from -40 °C to 75 °C, covering outdoor enclosures in cold climates and warm panel interiors.