What it is and where it lands
The Siemens 3RK1911-2BR10 is a connector socket insert — Han Q4/2 straight, 4 contact sockets rated for 4 mm² conductors, designed for the starter side of subsegment and spur line drops in a SIRIUS motor feeder architecture.
What it connects to
This insert mates with the Han Q4/2 hood/housing on the motor starter side, carrying the spur or subsegment power feed. The 4 mm² contact rating handles the typical branch circuit conductor size for SIRIUS S00 contactor assemblies. Straight orientation keeps the cable exit aligned with the DIN-rail wiring channel.