What this MCB is and what the ratings mean for fit
The Siemens 5SL6625-7 is a 4-pole (3P+N) SENTRON miniature circuit breaker rated 25 A with a C tripping characteristic, designed for 400 V AC multi-phase circuits and a 6 kA breaking capacity under both EN 60898 and IEC 60947-2. The C-curve means the magnetic trip operates at 5 to 10 times rated current — standard for general-purpose loads like lighting, small motors, and distribution subfeeds where moderate inrush is expected. The 6 kA rating tells you the breaker can safely interrupt a fault current up to that level at 400 V without upstream devices needing to clear it first, which governs selectivity coordination in the panel.
Physical fit and panel integration
At 72 mm wide (4 modular width units), 90 mm tall, and 76 mm deep with a 70 mm installation depth, this breaker occupies four standard 18 mm DIN-rail slots. The IP20 rating with connected conductors means it's protected against finger contact once wired — standard for enclosed distribution boards. Mounting position is unrestricted, and the sealable design allows panel locks or tamper-evident seals for metering or security applications.
Thermal and environmental limits
Each pole dissipates 2.6 W at rated current in hot operating state — relevant for thermal buildup in tightly packed enclosures. The breaker operates across a -40 °C to 75 °C ambient range, which covers most indoor and outdoor cabinet installations. Pollution degree 2 and overvoltage category III suit it for fixed-installation distribution boards in residential and infrastructure buildings.