What it is and what the key ratings mean
The Siemens 3RT2024-1DB40 is a SIRIUS power contactor in size S0, built for switching motor loads and resistive loads in control panels. The 24 V DC coil is the control voltage you need to match against your PLC or relay output — at that rated value, the auxiliary contacts handle 6 A, enough for signaling back to a controller or driving a small pilot light. The contactor is rated for up to 1 000 switching cycles per hour under AC-3 duty (motor starting), which is standard for conveyor and pump applications; drop to 300 cycles per hour under AC-4 (plugging/reversing) if you are doing frequent inching or reversing.
Where it fits and how it mounts
Size S0 means a 45 mm wide footprint on the DIN rail — screw and snap-on mounting onto 35 mm DIN rail per DIN EN 60715. The mounting position is flexible: +/-180° rotation on a vertical surface, and can tilt forward/backward by +/-22.5°, which helps when you are squeezing it into a crowded enclosure. Clearances: 10 mm upwards, 10 mm forwards, 10 mm downwards, 6 mm at the side. Depth is 151 mm, height 85 mm — check your enclosure depth before committing. The screw-type terminals on the magnet coil accept solid or stranded wire from 1 to 10 mm², and the auxiliary/main contact terminals take 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²). Operating temperature range is -25 to +60 °C, storage -55 to +80 °C.