What this MCB is and where it fits
The Siemens 5SL6315-7BB is a 3-pole miniature circuit breaker from the SENTRON family, with a C-curve tripping characteristic rated at 1.6 A and a 6 kA breaking capacity per EN 60898 and IEC 60947-2. It's built for 400 V AC three-phase circuits at 50 Hz, with a maximum multi-phase voltage of 440 V. The 3-module-width (54 mm) body snaps onto standard DIN rail and needs 70 mm installation depth behind the panel — the 76 mm overall depth includes the actuator and terminals.
What the ratings mean for your panel
The C-curve means the magnetic trip fires at 5–10× rated current — 8–16 A for this 1.6 A unit — so it's sized for moderate inrush loads like small motor starters or lighting banks where you need to ride through the start surge without nuisance tripping. The 6 kA breaking capacity at 400 V matches what you'll find in most residential and light commercial distribution boards; it's enough for fault currents typical in those settings. The derating table tells you what happens when the panel gets warm: at 40 °C ambient the breaker is good for 1.54 A, at 55 °C it drops to 1.43 A. If your enclosure runs hot, you either downrate the load or move up one frame size.
Integration and environment
Mounts in any position — upright, sideways, inverted — without derating the trip curve. Pollution degree 2 (normal industrial atmosphere, non-conductive dust) and overvoltage category III (permanent connection to the mains) cover the standard panel environment. The IP20 rating with conductors connected is typical for enclosed distribution boards; keep the front cover on during washdown. Touch protection is built into the terminals. Halogen-free and silicon-free construction matters if the panel lives in a clean room or near sensitive electronics where outgassing could fog contacts or optics.