Siemens 5SY7220-6 SENTRON MCB — 2-Pole, 20 A, B Curve
It carries dual breaking capacities: 15 kA per EN 60898-1 and 25 kA per IEC 60947-2, with UL 1077 recognition also listed.
Width is 36 mm, which is 2 modular units on a standard DIN rail. Mounting position is any orientation — no derating needed for horizontal vs vertical rail.
Temperature Performance and Derating
Rated 20 A at 35 °C ambient. At 40 °C it derates to 18.78 A, at 50 °C to 17.48 A, and at 60 °C to 16.08 A. Humidity tolerance is specified as max 95% up to 55 °C, then derating to 55% at 70 °C and 35% at 75 °C. For a panel near a furnace or in a hot attic, the 50 °C derated figure (17.48 A) is the one to size the load against — not the 20 A label.
Production status is current — this is an active catalog item, not a phase-out or NRND part. Standards compliance covers IEC/EN 60898-1, IEC/EN 60947-2, and UL 1077. Halogen-free and silicon-free construction. The product designation per EN 61346-2 and IEC 81346-2 is letter F. Suitability is marked for mechanical engineering and industry — the standard industrial MCB application.