The Siemens 3RF3310-3AA02 is a 1-pole solid-state contactor from the SIRIUS 3RF33 family, rated AC-1 10 A at 40 °C. That AC-1 rating means it's specified for resistive loads — heaters, lighting banks, or transformer primaries — where the switching cycle doesn't hammer the semiconductor junction with motor inrush. The control voltage range is 24-230 V AC / 24 V DC, so a single part covers both AC and DC control circuits across a wide voltage band — useful when you're standardizing one SKU across panels with different control transformers or 24 VDC PLC outputs.
Termination is via ring cable lug — not the spring-cage or screw-clamp you see on most DIN-rail contactors. That means the installer needs a crimp tool and ring terminals sized for the lug stud; it's a more vibration-resistant connection than a screw-clamp on stranded wire, which matters in high-vibration environments like compressor skids or conveyor drives. The package dimensions are 97 x 27 x 105 mm, so it occupies a single 27 mm-wide DIN-rail slot — standard for a 1-pole solid-state contactor in this current class.