What this 2-pole C-curve MCB carries
The Siemens 5SN6220-8CP is a 2-pole miniature circuit breaker from the SENTRON 5SN family, rated for 400 V AC multi-phase and single-phase operation (max 440 V), with a DC-side maximum of 72 V.
DIN-rail footprint and wiring
Occupies 2 modular width units (36 mm wide) on a DIN rail, with a depth of 76 mm and installation depth of 70 mm — fits standard 18 mm pitch enclosures. Accepts solid conductors up to 35 mm², so it can terminate larger feeder cables directly without a separate terminal block. Height is 90 mm, matching the SENTRON compact profile that leaves room for busbar bridging above.
Temperature range and power loss
Rated for ambient -40 °C to 75 °C, covering unheated electrical rooms and outdoor enclosures in most climates. Each pole dissipates 1.6 W in hot operating state at rated AC current — for a 2-pole unit that is 3.2 W total, negligible for thermal coordination in a crowded panel but worth checking if the enclosure is sealed and solar-loaded.