SIRIUS S0 Power Contactor — 3RT2028-2NF30
The Siemens 3RT2028-2NF30 is a SIRIUS S0-frame power contactor rated for switching motor loads in control panels. Coil pickup is 95-130 V AC; the magnet coil terminates on spring-type terminals for fast wiring without screwdriver torque. Main contacts are rated for AC-3 duty at 18 A (the contact rating for motor switching) and the contactor fits the 45 mm wide S0 footprint — a standard panel cutout shared across the SIRIUS contactor family.
Mounting and Integration
Fastens via screw and snap-on mounting onto 35 mm DIN rail per DIN EN 60715. The mounting position allows +/-180° rotation on a vertical surface, plus +/-22.5° forward/backward tilt — useful when panel layout forces an unusual orientation. Dimensions: 102 mm height, 45 mm width, 107 mm depth. Clearance: 10 mm upward, 10 mm forward, 10 mm downward, and 6 mm at the side for arc-flash and heat dissipation.
Coil and Auxiliary Ratings
Coil inrush current peaks at 15 A; holding power factor is 0.79 at 50 Hz and 0.74 at 60 Hz. The pick-up voltage range is 0.7 to 1.3 times rated value — so the coil seals in reliably at 66.5 V AC and holds through 169 V AC. Auxiliary switch contacts are rated 10 A at 24 V, 2 A at 48 V and 60 V, and 1 A at 110 V — sufficient for signaling back to a PLC input module or for interlocking a downstream contactor.