Siemens 5SY6225-6 SENTRON 2-Pole MCB, 25 A Type B
Breaking capacity is 6 kA per IEC/EN 60898-1 and 15 kA per IEC/EN 60947-2 / UL1077, so it covers most panelboard and sub-distribution applications up to those fault levels without needing an upstream current-limiting fuse.
Mounts in any position; terminals accept combined top/bottom feed, and the unit is sealable for tamper-proofing after commissioning.
Thermal derating and environment
Rated 25 A at 35 °C; derates to 23.48 A at 40 °C, 22.68 A at 45 °C, 21.85 A at 50 °C, and 21 A at 55 °C — so in a warm panel the actual continuous current you can carry is lower than the label rating. Ambient range -40 °C to 75 °C; humidity limits apply: max 95% up to 55 °C, tapering to 35% at 75 °C. Halogen-free and silicon-free construction.