The Siemens 5SY7140-8CC is a SENTRON miniature circuit breaker, 1-pole, rated 40 A at 400 V AC with a D tripping characteristic — that's the high-inrush curve for motor and transformer circuits where the start-up surge would nuisance-trip a B or C curve. It breaks 15 kA under IEC 60947-2 and 5 kA under UL 1077 / CSA C22.2 No.235, so it handles fault currents up to those levels without welding or cascading upstream. The D-curve means the magnetic trip is set at 10–20× In (400–800 A), sized for loads like small conveyors, compressors, or pump starters that draw a heavy inrush on power-up.
Snaps onto DIN rail via the quick-assembly system — 18 mm width (1 MW), 90 mm height, 76 mm depth. Accepts solid or stranded conductors from 0.75 to 35 mm²; screw terminals torque to 2.5–3.5 N·m. IP20 with conductors connected, so it's panel-only — not for wet or washdown zones. Ambient range -25 to +55 °C, storage -40 to +75 °C. Mounting position any, so it fits vertical or horizontal busbars without derating. Overvoltage category III, suitable for fixed-installation distribution boards in mechanical engineering and industrial environments.
Halogen-free and silicon-free construction — relevant for clean-room or sensitive electronics environments where outgassing can't be tolerated. Sealable (padlockable) for lockout/tagout compliance. Touch protection integrated. Combined terminal top and bottom simplifies daisy-chaining busbars or looping feed-through. Neutral conductor switching not included — this is a 1P breaker, line only.