SENTRON 5SL6450-7MB — 4-pole C-curve MCB for 400 V distribution
The Siemens SENTRON 5SL6450-7MB is a 4-pole miniature circuit breaker rated 50 A at 400 V AC with a C tripping characteristic and a 6 kA breaking capacity according to EN 60898.
The 6 kA breaking capacity at 400 V AC per EN 60898 tells you it can safely interrupt fault currents up to that level without upstream cascading; for higher prospective fault currents you'd step to a 10 kA rated unit like the 5SL4363-7 (3-pole) or 5SY5416-7 (4-pole, 10 kA). Power loss per pole is 3.5 W in hot operating state at rated current — at 4 poles that's 14 W total heat to dissipate inside the enclosure. Factor that into your thermal budget if the board is tightly packed or in a high-ambient location.
The 4-module width (72 mm) matches the standard SENTRON 5SL series footprint — it shares the same housing as the 4-pole 5SY series breakers, so cutouts and busbar positions are consistent across the family.