The Siemens 5SL6303-6CC is a 3-pole miniature circuit breaker rated 400 V with a 6 kA breaking capacity, B-curve trip characteristic, and 3 A rated current. This is the Basic Devices family member — the standard-issue MCB for 3-phase final subcircuits in commercial and light industrial distribution boards. The B-curve (3-5 In) means it's sized for resistive and general-purpose loads where inrush is modest; it's the go-to for lighting, socket outlets, and control transformers, not motor-starting duty.
Integration Note
Snap-on DIN rail mount, 3-pole width (approx. 54 mm). Terminal capacity for 0.75–25 mm² conductor. The 6 kA breaking capacity at 400 V is adequate for most commercial distribution boards where the prospective fault current stays under that threshold — verify your point-of-installation SCCR before committing the BOM line. For a panel OEM, this is a standard 3-module MCB that slots into any 35 mm DIN-rail enclosure alongside RCBOs and contactors.