Siemens 3RT2628-1NB35 — SIRIUS Contactor Relay, 21-28 V AC/DC Coil
The Siemens 3RT2628-1NB35 is a SIRIUS contactor relay with a 21-28 V AC/DC coil, screw-type terminals, and a 45 mm width that snaps onto 35 mm DIN rail per DIN EN 50022. Its 165 mm depth and 150 mm height fit standard panel layouts, and the mounting position allows +/-180° rotation on a vertical surface plus +/-22.5° tilt forward or backward.
Contact Ratings and Switching Capacity
The auxiliary contacts are rated 6 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 1 A at 690 V — covering control-circuit voltages from 24 VDC up to 690 VAC. Maximum switching frequency varies by voltage: 100 operations per hour at 230/240/400 V, dropping to 36 per hour at 690 V, which governs the relay's duty cycle in high-voltage switching applications.
Screw-type coil terminals accept solid conductors: 2x (0.5-1.5 mm²), 2x (0.75-2.5 mm²), or 2x 4 mm². Stranded conductors: 2x (1-2.5 mm²) or 2x (2.5-10 mm²). Power-side terminals accept 1x 16 mm² at 40 °C or 1x 25 mm² at 60 °C, allowing flexibility in main-circuit wiring gauge based on ambient temperature.