What this 2 A B-curve MCB is for
The Siemens 5SL4202-6CC is a 2-pole SENTRON miniature circuit breaker rated 2 A at 400 V AC with a B tripping characteristic and 10 kA breaking capacity per EN 60898. It protects branch circuits in residential and infrastructure panels — think lighting, general-purpose outlets, and small resistive loads where the B-curve's magnetic trip at 3–5× rated current keeps nuisance trips off sensitive electronics.
The 2 A rating governs the continuous load the breaker can carry — size it for a circuit that draws under 1.6 A continuous to stay within the 80 % derating rule for continuous loads per NEC. The B-curve trips magnetically between 3× and 5× rated current (6–10 A), so it's a good match for resistive loads and short cable runs where inrush stays low; don't use it on motor circuits or transformers that see a higher starting surge — that's C- or D-curve territory. The 2-pole construction switches both phase and neutral on a single-phase circuit, or two phases on a split-phase system. Note that neutral conductor switching is not provided — this breaker does not include a switched neutral pole, so the neutral path is solid through the device. Overvoltage category 3 and pollution degree 2 confirm it's rated for fixed-installation panels where transient overvoltages and normal indoor contamination are expected. Physical fit: 36 mm width — that's 2 width units at 18 mm per pole — and 76 mm depth with 70 mm installation depth. Height is 90 mm.
Vibration resistance tested to 50 m/s² over 25–150 Hz per IEC 60068-2-6 — solid for transport and moderate machine vibration. The breaker is sealable — a lead seal can be passed through the housing to prevent tampering after commissioning, useful for metered or rental subpanels.