What this part is and what it does
The Siemens 3RT1934-5BW42 is a SIRIUS magnet coil designed for Size S2 contactors, operating on a 48 V DC control supply voltage using spring-loaded connection technology.
What the 48 V DC rating means for fit
The 48 V DC coil rating determines the control voltage required to pick and hold the contactor. In a 48 V DC control circuit, this coil draws its rated inrush and holding power, so verify your control transformer or power supply is sized for the coil's VA demand at 48 V. The spring-loaded connection (cage clamp) accepts solid or ferruled stranded wire without requiring screw tightening, which speeds panel wiring and resists vibration loosening.
Panel integration note
This coil mounts to the Size S2 contactor body, which snaps onto a 35 mm DIN rail per DIN EN 50022. The spring-loaded terminals accept 2x (0.5 to 1.5 mm²) or 2x (0.75 to 2.5 mm²) solid or ferruled stranded conductors.