Siemens 5SL6120-6YA SENTRON MCB — 20 A, B-curve, 1-pole
The Siemens 5SL6120-6YA is a 1-pole miniature circuit breaker from the SENTRON family, rated 20 A with a B-tripping characteristic and a 6 kA breaking capacity per EN 60898.
Rated 20 A at 30 °C ambient, with a slight derating at elevated temperatures: 18.4 A at 45 °C, and a sharp drop to 0.95 A at 40 °C — that 40 °C figure appears to be a data anomaly or a different test condition, so size for the 30 °C rating and apply standard IEC derating if the enclosure runs hot.
Mechanical fit and environmental specs
Sealable design allows tamper-proof locking for metering or safety isolation.