The Siemens 3SF5402-1AB05 is an AS-Interface F-adapter designed specifically for the SIRIUS 3SB3 EMERGENCY-OFF control device range. It mounts on the front of a mushroom-type emergency-stop actuator, converting the mechanical pushbutton into two AS-i safe digital inputs and one standard output for LED status indication. The connection uses the AS-i insulation displacement method, so no separate screw terminals are needed for the bus — the adapter pierces the flat cable directly.
The two safety-related inputs are what make this an F-adapter — they carry the E-stop circuit's dual-channel signal onto the AS-i safety bus, meeting the redundancy required for SIL 3 / PL e applications. The single output drives the LED in the mushroom-head actuator, giving operators a clear visual that the E-stop is pressed.
Front mounting — the adapter clips onto the back of the 3SB3 actuator from inside the panel, so the actuator bezel stays on the enclosure door. Dimensions are compact: 52 mm deep, 30 mm wide, 61 mm tall. The insulation displacement connection means the AS-i flat cable is pressed into the adapter's IDC slots; no stripping, no ferrule, no screwdriver. Check that your AS-i cable is the standard round-profile flat type — the IDC contacts are sized for that profile.