The Siemens 5SL4403-6CC is a 4-pole miniature circuit breaker (MCB) from the Basic Devices family, rated 3A with a B tripping characteristic at 400V AC and a 10kA breaking capacity. The B-curve means it trips magnetically between 3x and 5x rated current (9A to 15A), which suits resistive and light inductive loads like lighting circuits, small transformers, or control power supplies — not high-inrush motor starting, where a C or D curve would be a better fit. The 10kA breaking capacity at 400V means it can safely interrupt a fault current up to 10,000A without welding contacts or cascading failure upstream, which is standard for most commercial and light industrial distribution boards.
Sourcing posture
No minimum above the single-piece unit quantity.