The Siemens 3SF5500-0CA is an AS-i F-slave module with two safe digital inputs, designed specifically for mounting into an emergency stop housing. The metal housing (no protective collar) and IP20 rating mean it lives inside a control cabinet or enclosed operator station — not on the machine frame exposed to washdown. The two safe inputs let you wire a dual-channel e-stop or two single-channel safety devices into one AS-i safety node, keeping the bus wiring simple.
Floor mounting — this isn't a DIN-rail clip. The 17.6 mm width and 50.1 mm depth fit into the cutout of a standard emergency stop housing enclosure. Panel builders: plan for the 71 mm height clearance above the mounting surface.