Direct-on-line starter in SIRIUS S0 frame
The 3RA2120-1GA24-0FB4: This is a Siemens SIRIUS direct-on-line starter, combining a contactor and overload relay in one Size S0 package. The supplied contactor is 3RT2024-1FB40 and the link module is 3RA2921-1BA00, making this a factory-assembled combination that saves panel wiring time.
AC-3 rating and trip class — what they mean on the line
The maximum AC-3 operating voltage is 690 V. Control voltage is 24 VDC, a common PLC-level signal that keeps the control circuit isolated from the motor power side.
Panel fit and clearances
The S0 frame measures 45 mm wide, 107 mm deep, and 193 mm high — it occupies one standard 45 mm slot on a 35 mm DIN rail. Mounting position is vertical. Required clearances around the device: 50 mm upwards, 20 mm forwards, 20 mm at the sides, 10 mm downwards, and 0 mm backwards — useful to know when laying out a crowded panel.
Environmental range and production status
Operating temperature range is -20 to +60 °C, with storage and transport limits of -50 to +80 °C. Temperature compensation is active across the full operating range.