What it is and where it fits
The Siemens 3RT2024-1BM44 is a SIRIUS power contactor in Size S0, designed for switching motor loads and resistive loads in industrial control panels. It mounts via screw or snap-on onto 35 mm DIN rail per DIN EN 60715, fitting a 45 mm wide slot — standard for a 3-pole contactor in this frame size. Main contacts are rated 16 to 8 A, with screw-type terminals accepting solid or stranded conductors from 1 to 10 mm². The operating temperature range of -25 to +60 °C covers most indoor panel environments without derating.
Key ratings and what they mean for fit
The 16-8 A main contact rating is the continuous current range for the power circuit — the contactor is sized for loads up to 16 A, with the lower end (8 A) reflecting the minimum reliable switching current for the silver-alloy contacts. For motor duty, the AC-3 switching frequency of up to 1 000 operations per hour means it can handle frequent starts and stops on a conveyor or pump without overheating the coil or contacts. Depth of 151 mm is the dimension from the DIN rail mounting surface to the front of the contactor — critical for enclosure depth planning when the panel door has a disconnect or HMI mounted close. The 45 mm width and 85 mm height match the S0 footprint, leaving 10 mm clearance upwards, downwards, and forwards, and 6 mm at the side for airflow and wiring access.