SIRIUS S0 direct starter — what the 5.5 kW rating means for a motor line
The 3RA2125-1KE24-0FB4: The unit ships as a pre-assembled set: contactor 3RT2024-2FB40, circuit breaker 3RV2021-1KA25, and link module 3RA2921-2AA00 — one order code, one BOM line, ready to rail-mount.
Panel fit — DIN rail, spring terminals, and the 45 mm width
Main and control circuits both terminate with spring-loaded terminals — no torque driver needed, vibration-resistant, and faster to wire than screw-clamp on a production build. Vertical mounting position is specified; the 107 mm depth leaves clearance behind a 200 mm deep enclosure door for wiring and finger-safe shrouding.
Auxiliary switch and coordination
The starter accepts an auxiliary switch extension for status feedback to a PLC or HMI — useful for confirming the contactor state in a safety-related monitoring circuit. Surge voltage resistance is 6 kV, which supports coordination with Type 2 surge arrestors upstream in the distribution panel.