The Siemens 3SF5814-2DA00 is an AS-Interface enclosure with 4 command points — a pushbutton/knob/dummy plug combination — rated for 26.5 to 31.5 VDC supply. It carries 3 switching elements with positive opening (the NC contacts physically break, even if welded), and the red mushroom-head actuator uses a rotate-to-unlatch mechanism. The housing is metal, IP67-rated, and comes pre-wired on a strip terminal.
Floor-mount this enclosure vertically — the 22 mm mounting diameter and rectangular metal housing (194 mm high, 85 mm wide, 65 mm deep) suit panel doors or standalone pedestals. IP67 means it handles washdown environments: food processing, car washes, outdoor conveyor lines. The pre-wired strip terminal saves panel-builder wiring time; just land the AS-i bus and the 3 switching-element circuits.
Positive opening is the safety-relevant detail: the NC contacts are mechanically forced open when the actuator is pressed, even if the contacts have welded. That makes this unit suitable for emergency-stop circuits in machinery guarding per IEC 60947-5-1. The rotate-to-unlatch requires a deliberate twist to reset — no accidental re-energisation. IP67 means dust-tight and protected against temporary immersion; fine for washdown zones. Vibration tested to 5g at 20-200 Hz — survives the shake on a vibrating conveyor or pump skid.