What this contactor is and where it fits
The Siemens 3RT2024-1BE40 is a SIRIUS power contactor in the S0 frame size, rated for main contacts from 16 to 8 A. It includes an auxiliary switch and uses screw-type terminals for the magnet coil and main circuit wiring. Mounting is via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, making it a direct fit for standard industrial control panels. The S0 frame is a common size for motor loads up to roughly 7.5 kW at 400 V, depending on duty class. Operating temperature range is -25 to +60 °C, with storage from -55 to +80 °C, so it handles typical enclosure environments without derating concerns in most plant-floor conditions.
Key ratings and what they mean for your panel
The 16 to 8 A rating on the main contacts is the thermal continuous current range for the contactor's power poles. For motor switching (AC-3 duty), the actual making/breaking current is lower — this contactor is sized for the load, not the bus. Mechanical life is typical 10,000,000 operations, and electrical life at AC-3 maximum is 1,000 operations per hour. At AC-4 (inching/jogging) that drops to 300 operations per hour, so plan for higher wear in reversing or plugging applications. Wire capacity accepts solid or stranded conductors from 1 to 10 mm², with dual-wire capability for smaller gauges (2x 0.5 to 1.5 mm² or 2x 0.75 to 2.5 mm²). This covers most panel wiring from control circuits to motor feeds.
Mounting and spacing requirements
Dimensions are 85 mm height, 45 mm width, and 107 mm depth. The S0 footprint is compact enough for dense panel layouts, but clearance matters: allow 10 mm upwards, 10 mm forwards, 10 mm downwards, and 6 mm at the side for arc flash and heat dissipation. Mounting position allows +/-180° rotation on a vertical surface, plus +/-22.5° tilt forward/backward. This flexibility helps when fitting into existing enclosures or odd-angle subpanels.