Siemens SIRIUS 3RT2026-1FB48-0GS2 — Power Contactor, S0 Frame, 24 VDC Coil
The Siemens 3RT2026-1FB48-0GS2 is a SIRIUS power contactor in the S0 frame size, designed for switching motor loads and resistive loads in industrial control panels. It mounts via screw or snap-on onto a 35 mm standard mounting rail per DIN EN 60715, which is the standard DIN-rail footprint for panel integration. The coil is rated at 24 VDC, and at that rated value the holding current draws 6 A — a figure to account for in your DC supply budget, particularly if multiple contactors share a single power supply. The contactor measures 45 mm wide by 85 mm tall by 151 mm deep, fitting the S0 envelope. The screw-type terminals accept solid or stranded conductors from 1 to 10 mm², which covers most motor branch-circuit wiring up to the contactor's rating. The main contacts are rated for 16 to 8 A depending on the duty cycle — the specific AC-3 motor-switching current isn't listed here, but the frame size and terminal range indicate it handles typical fractional-to-small-horsepower motor loads.
Duty Cycles and Switching Frequency — What the Ratings Mean
The maximum switching frequency varies by duty class: 1,000 operations per hour at AC-1 (resistive loads), 750 per hour at AC-2 and AC-3 (motor starting and running), and 250 per hour at AC-4 (plugging or inching). These are the contactor's thermal limits for the main contacts — exceeding them shortens electrical life or risks contact welding. For a conveyor drive running continuous AC-3 duty, 750 ops/h is generous; for a press that cycles at 300 ops/h in AC-4, the 250 ops/h ceiling is the binding constraint. The arcing time is 10 to 10 ms — a tight window that indicates consistent arc extinction across the switching range. The DC coil operates with a dropout time of 15 to 17.5 ms, which matters for sequencing logic where you need predictable de-energization timing.
Environmental Limits and Mounting Position
Operating ambient temperature spans -25 to +60 °C; storage range is -55 to +80 °C. The mounting position allows +/-180° rotation on a vertical surface and can be tilted forward or backward by +/-22.5° — useful when fitting into tight enclosures where the DIN rail isn't perfectly vertical. Clearances: 10 mm upwards, forwards, and downwards, and 6 mm at the side. The enclosure protection rating is IP20 on the front and at the terminals, so it's suitable for dry indoor panels only — no washdown or outdoor exposure without an additional enclosure.