The Siemens SENTRON 5SJ4125-8HG41 is a 1-pole miniature circuit breaker with a D tripping characteristic, rated 25 A at both 30 °C and 40 °C ambient. Mounts on standard DIN rail, any position, and takes up a single modular width (18 mm). The IP20 body with IP40 in the handle range means it's panel-protected but not washdown-rated.
The 25 A rating holds steady up to 40 °C; above that it derates — 24.25 A at 45 °C, 23.5 A at 50 °C, 22.7 A at 55 °C, 22 A at 60 °C. DC rated at 60 V maximum — fine for control circuits but not for higher-voltage DC bus work. Vibration resistance tested at 50 m/s² over 25–150 Hz and 60 m/s² at 35 Hz (4 s) — holds up on machinery with moderate vibration.