The Siemens SENTRON 5SJ4245-7HG41 is a 2-pole miniature circuit breaker with C tripping characteristic, rated 45 A at both 30 °C and 40 °C ambient. The 36 mm width (2 modular units) and 70 mm depth match the 5SJ4 family footprint — a direct swap for an earlier 5SJ4 unit or a drop-in for a panel originally built around the 5SL6550-7BB, provided the terminal arrangement (combined screw terminals top and bottom, no tunnel terminals) is compatible.
Rated 45 A at 40 °C — the same as at 30 °C, so no early derating in a warm panel. Above 40 °C the curve steps down: 44.1 A at 45 °C, 43.2 A at 50 °C, 42.2 A at 55 °C, 41.4 A at 60 °C. That means a 45 A circuit at 50 °C still holds 96 % of its rating; a designer sizing for a 50 °C panel ambient can treat it as a 43 A breaker without over-specifying.
Vibration resistance tested to 50 m/s² at 25–150 Hz and 60 m/s² at 35 Hz (4 s) — adequate for machine-mounted panels on pumps or compressors.
Listed as current-production lifecycle stage. No end-of-life notice or successor code found.