The Siemens SIRIUS 3RT1934-5BB41 is a magnet coil for Size S2 contactors, rated 24 V DC with screw terminals. It is a replacement coil for the 3RT1 contactor series, designed to snap onto the contactor's coil terminals within a control panel.
What the ratings mean for fit
The 24 V DC rated value is the coil's nominal operating voltage. At this voltage the coil pulls in and holds the contactor armature; the dropout voltage is typically around 18 V DC. The DC control supply means the coil is polarity-sensitive — verify free-wheel diode polarity if the circuit uses a suppression diode across the coil. Size S2 corresponds to the contactor frame size. This coil fits 3RT1 contactors in the S2 frame only — it will not physically mount on S0, S00, S3, or S6 frames. The screw terminal connection matches the contactor's coil terminals; no additional wiring adapter is needed.
Panel integration note
The coil snaps onto the contactor's front face. The contactor itself mounts on a 35 mm DIN rail per EN 50022. No additional panel space is consumed beyond the contactor footprint. The screw terminals accept 0.5–2.5 mm² solid or stranded wire, or 2x (0.75–2.5 mm²) with ferrule.
