The Siemens 3RT2645-1NB35 is a SIRIUS 3RT2 series contactor with a screw-type AC/DC magnet coil rated for 20–33 V. It switches 6 A at 24 V and handles up to 2 A at 60 V, 1 A at 110 V, 0.9 A at 125 V, 0.3 A at 220 V, 6 A at 230 V, 3 A at 400 V, and 0 A at 690 V — so the contact ratings drop sharply above 400 V; for 690 V circuits you need a different frame. The 80 mm width and 152 mm depth mean it takes two standard DIN modules — a panel builder will note that.
Termination and wire capacity
Solid wire connections: 2x (0.5–1.5 mm²), 2x (0.75–2.5 mm²), and 2x 4 mm². Stranded: 2x (10–70 mm²) or 1x (10–70 mm²). At 40 °C the main circuit accepts 1x 50 mm²; at 60 °C derates to 2x 35 mm². The screw terminals are standard for this class — no push-in here, so plan for screwdriver access.
The 3RT2645-1NB35 is in active current production — no obsolescence notice.