What it is — and what the ratings mean for fit
The Siemens 5SL6540-7CC is a 1+N-pole miniature circuit breaker rated 230 V with a 6 kA breaking capacity, C-curve trip characteristic, and 40 A rated current. It belongs to the Basic Devices family within the Siemens 5SL6 series of MCBs. The C-curve (trip between 5× and 10× In) means this 40 A breaker handles moderate inrush loads — think small motor starters, banks of LED drivers, or control transformers — without nuisance tripping on start-up, while still clearing short circuits fast. The 6 kA short-circuit capacity at 230 V is sized for residential and light commercial distribution boards; for industrial panels with higher prospective fault current, you'd step up to a 10 kA or 15 kA rated MCB. The 1+N-pole configuration switches both line and neutral, with overcurrent protection on the line pole only. That's standard for single-phase final subcircuits where you want the neutral switched for isolation but don't need to protect it thermally.
Lifecycle and compliance — active, RoHS, REACH
RoHS compliance is confirmed since June 2013. REACH Article 33 duty-to-inform documentation is available per the current candidate list. Export control classifications are AL: N / ECCN: N — no license required for most destinations. Product class B means this is a return-restricted item — Siemens requires direct partner contact for returns. Not a showstopper, but worth noting if your procurement process expects blanket return rights.
Where it fits in the panel
Snap-on DIN rail mounting, standard 18 mm per pole width. The 1+N unit occupies two modules (36 mm) on the rail. Wire termination accepts copper conductors up to 25 mm² for the line and load terminals — busbar-compatible for grouped distribution. Rated for 230 V AC, 50/60 Hz. The C-curve 40 A rating is a common choice for general-purpose socket circuits, lighting banks, and small resistive or mixed loads in commercial and residential final distribution boards.