The Siemens 3RT2636-1NB35 is a SIRIUS 3RT2 contactor with a 24 VDC coil, rated to switch 6 A at 230 V and 3 A at 400 V. The AC/DC coil type means it accepts either supply, simplifying panel wiring where both voltages are present.
Switching Capacity and Duty Cycle
The contactor's switching capacity varies by voltage: 6 A at 24 V, 6 A at 230 V, 3 A at 400 V, and 0 A at 690 V — meaning it is not rated for 690 V switching. Maximum switching frequency drops from 100 operations per hour at 230 V to 30 per hour at 690 V, so for high-cycle applications like rapid conveyor indexing, keep the load voltage below 400 V to maintain rate.
The coil uses screw-type terminals. Main power terminals accept solid conductors: 2x (0.5 to 1.5 mm²), 2x (0.75 to 2.5 mm²), or 2x 4 mm². For stranded wire, the range is 2x (10 to 35 mm²) or 1x (10 to 50 mm²). At 40 °C ambient, a single 35 mm² conductor is rated; at 60 °C, a single 50 mm² conductor. This gives flexibility for both control-circuit and power-circuit wiring in a mixed-gauge panel.
Mounting and Positioning
This flexibility helps when routing cables in tight enclosures or aligning with existing busbars.