What this 4-pole D-curve 50 A MCB covers
The Siemens 5SY6450-8 is a SENTRON 5SY6 miniature circuit breaker rated 50 A at 400 V AC, 4 poles, with a D tripping characteristic. Breaking capacity is 6 kA per EN 60898 and 10 kA per IEC 60947-2, with a 5 kA interrupting rating per UL 1077 / CSA C22.2 No.235 for North American panels. It also carries a 15 kA DC rating per IEC 60947-2 at 72 V DC max, useful for string-level solar combiner boxes or battery circuits.
Mounts via quick-assembly system (DIN rail) in any position. Occupies 4 width units (72 mm wide, 90 mm tall, 76 mm deep, 70 mm installation depth). Touch protection is built in; sealable for tamper-proofing.
Rated for ambient -25 to +55 °C operating, -40 to +75 °C storage. Halogen-free and silicon-free construction. Overvoltage category III. Humidity tolerance: 95% at 55 °C, derating to 35% at 75 °C. Suitable for mechanical engineering and industrial environments per the manufacturer's designation.