Siemens SENTRON 5SL4303-7CC — 3 A, C-curve, 3-pole MCB
The Siemens SENTRON 5SL4303-7CC is a 3-pole miniature circuit breaker rated 3 A at 400 V AC, with a C tripping characteristic and a 10 kA breaking capacity tested to EN 60898. It occupies 3 width units (54 mm) on a DIN rail and is designed for residential and infrastructure branch-circuit protection. The C-curve means the magnetic trip activates at 5 to 10 times rated current — suited for moderate inrush loads like small motors, lighting, and general-purpose circuits where the start-up surge is higher than a resistive load but not extreme. Rated for 50 Hz AC supply, with a multi-phase operating voltage up to 440 V. The 10 kA breaking capacity at 400 V is the standard domestic and light-commercial fault level across most European installations.
Lifecycle and sourcing posture
The 5SL4303-7CC carries a pollution degree 2 rating and overvoltage category III, meeting the requirements for fixed-installation switchgear in residential and commercial panels.
Panel integration and physical fit
Mounts on a standard 35 mm DIN rail in any position. The 54 mm width (3 modular units) and 76 mm depth fit standard distribution boards. Installation depth is 70 mm behind the panel face. IP20 protection with connected conductors — suitable for enclosed distribution boards where the front face is covered. Touch protection is integrated on the terminals. Halogen-free and silicon-free construction, relevant for installations in environments sensitive to outgassing (clean rooms, data centers, or areas with silicone-based sealants).
Environmental and compliance range
Operates from -40 °C to +75 °C ambient, with a maximum 95% humidity at 55 °C. Vibration resistance tested to 50 m/s² at 25 to 150 Hz per IEC 60068-2-6. Sealable design allows the installer to lock the toggle position after commissioning, preventing unauthorized switching.