The Siemens 5SY4620-6 is a SENTRON miniature circuit breaker in a 4-pole 3P+N configuration, rated 20 A at AC with a B tripping characteristic. It carries dual interrupting ratings: 10 kA under EN 60898-1 and 20 kA under IEC 60947-2 / UL1077, so it covers both residential-distribution board and industrial panel applications depending on the standard the local code follows. The B curve means it trips between 3 and 5 times rated current — suited for resistive or general-purpose loads where inrush is moderate, not for motor-starting duty.
Panel fit and mounting
Occupies 4 modular width units (72 mm wide) on a DIN rail. Depth is 76 mm, installation depth 70 mm. The quick-assembly fastening system snaps onto the rail without tools. Mounting position is any — no derating needed for horizontal vs vertical orientation. The combined top and bottom terminals accept conductors with touch protection built in. Sealable design allows the installer to lock the handle position for lockout/tagout.
Thermal derating and environment
Rated 20 A at 35 °C ambient. Derates to 19.04 A at 40 °C, 18.54 A at 45 °C, 18.04 A at 50 °C, 17.5 A at 55 °C, and 16.96 A at 60 °C. If the panel runs warm, size the upstream protection accordingly. Ambient operating range is -40 to 75 °C. Humidity limits: 95% RH up to 55 °C, derating to 55% at 70 °C and 35% at 75 °C. Pollution degree 3, overvoltage category III — suitable for industrial environments with conductive contamination.