What It Is and Where It Fits
The Siemens SIRIUS 3RT2027-1NP30-ZX95 is a Size S0 power contactor from the SIRIUS family, designed for switching motor and resistive loads in industrial control panels. It mounts via screw and snap-on onto 35 mm DIN rail per DIN EN 60715, with a 45 mm width and 107 mm depth that fits standard panel layouts. The magnet coil is rated for 200... 280 V AC with screw-type terminals, drawing an inrush peak of 25 A. The coil hold-in and dropout characteristics follow the standard SIRIUS contactor curve — expect reliable pick-up down to roughly 85% of rated voltage.
Key Ratings and What They Mean for the Buyer
The contactor's operating temperature range of -25... +60 °C covers most indoor panel environments, including unventilated enclosures near machinery. The storage range of -55... +80 °C allows for cold warehouses without concern. Switching frequency limits are specified by duty class: 1 000 cycles/hour at AC-1 (resistive loads), 750 cycles/hour at AC-3 (motor starting/running), and 250 cycles/hour at AC-4 (plugging/inching). For high-cycle applications like conveyor indexing, the AC-3 limit of 750 operations per hour is the governing figure — exceeding it risks accelerated contact wear. The auxiliary switch (built-in) provides rated values of 10 A at 24 V, 2 A at 48 V, 2 A at 60 V, and 1 A at 110 V. These are the DC-13 ratings for inductive loads — a common trap is assuming the 24 V figure holds at higher voltages. It does not; plan your control circuit accordingly.
Mechanical Fit and Wiring
The S0 frame size accepts main contact wiring of 1... 10 mm² solid or stranded, with dual-wire capability for 2x (0.5... 1.5 mm²) and 2x (0.75... 2.5 mm²). The mounting position allows +/-180° rotation on a vertical surface and +/-22.5° tilt forward/backward, giving flexibility in tight enclosures. Clearance distances: 10 mm upwards, forwards, and downwards; 6 mm at the side. These are the minimum air gaps to adjacent metalwork or other devices — respect them to avoid flashover at rated voltages.