What this MCB is and what it does
The Siemens 5SL6140-7RC is a SENTRON miniature circuit breaker, 1-pole, rated 40 A at AC with a C-curve trip characteristic. It breaks fault currents up to 7.5 kA per EN 60898 at 415 V AC — that's the standard for residential and light commercial distribution boards. The C-curve means it trips between 5 and 10 times rated current, so it handles moderate inrush from motorized loads like pumps or small compressors without nuisance tripping on start-up.
Physical fit and panel integration
One modular-width unit (18 mm) on standard DIN rail. Depth is 76 mm, installation depth 70 mm — that's the dimension you need for enclosure depth clearance. IP20 with connected conductors, so it's intended for enclosed distribution boards, not wet or dusty environments. Mounting position is any, which helps when you're packing a tight panel layout.
Environmental and compliance notes
Rated for ambient temperatures from -40 °C to 75 °C, so it works in unheated utility rooms or outdoor-adjacent enclosures. Halogen-free and silicon-free construction — relevant if you're specifying for environments where outgassing matters, like clean rooms or certain industrial processes. Sealable design allows locking the toggle position to prevent unauthorized reset.