The Siemens 5SY4306-6 is a SENTRON-series miniature circuit breaker (MCB) in a 3-pole, B-characteristic configuration. It snaps onto a DIN rail in a standard 3-module-width footprint (54 mm wide, 90 mm tall, 76 mm deep with 70 mm installation depth). Rated 400 V AC (440 V max multi- or single-phase) and 60 V DC (72 V max), it handles 50/60 Hz circuits. The interrupting capacity tells you where it can go: 10 kA per EN 60898-1 for standard household/commercial panels, 35 kA per IEC 60947-2 for industrial distribution where fault currents run higher, and 5 kA per UL 1077 / CSA C22.2 No.235 for North American supplementary protection.
Sealable terminals (yes) let you lock the cover after commissioning, which some specs require for tamper-proofing. Mounts in any position, fastens via the quick-assembly system (the standard DIN-rail clip). Temperature derating: the breaker is rated for ambient up to 75 °C, but the surrounding temperature influence table (max 95% RH at 55 °C, dropping to 35% RH at 75 °C) means you need to watch humidity in hot enclosures. Below -40 °C the mechanical trip may not reset reliably — that's the storage/transport floor, not an operating spec.
DC-side capability
Rated 60 V DC (72 V max) with a 15 kA interrupting capacity per IEC 60947-2. The DC rating is lower than the AC one because DC arcs are harder to extinguish; the 15 kA figure is still substantial for a 3-module-wide MCB.