The Siemens 5SL6406-7MB is a SENTRON miniature circuit breaker (MCB) with a 4-pole design, C-trip characteristic, and a 6 A rated current at 400 V AC. Its 6 kA breaking capacity per EN 60898 covers the majority of residential and light commercial fault-current scenarios, making it a standard choice for final-distribution subcircuits in building infrastructure.
Ratings and what they mean for panel fit
The C-curve means the magnetic trip activates at 5 to 10 times rated current — suited for circuits with moderate inrush, such as lighting banks or small motor loads. At 6 A, this breaker protects a 1.5 mm² copper conductor on a 400 V three-phase line. The 6 kA breaking capacity is the maximum prospective fault current it can safely interrupt per EN 60898; for installations with higher available fault current, a current-limiting upstream device or a higher-rated MCB (e.g., 10 kA) would be needed. Rated insulation voltage is 440 V AC for multi-phase operation, and single-phase operation is rated at 250 V AC. Overvoltage category III and pollution degree 2 confirm it is designed for fixed installations inside a building's distribution board — not for outdoor or wet-location mounting without additional enclosure. Mechanical service life is 10 000 switching cycles typical. The breaker occupies 4 modular width units on a DIN rail, with a width of 72 mm, depth of 76 mm, and height of 90 mm. Installation depth is 70 mm, and mounting position is any orientation.
Integration notes
Snap-on mounting to a 35 mm DIN rail per EN 60715. The 4-pole design switches all three phases and leaves the neutral solid — no integrated neutral conductor switching. Terminal protection is IP20 with connected conductors, standard for enclosed distribution boards. The housing is halogen-free and silicon-free, and the breaker is sealable for tamper-proofing after commissioning.