The Siemens 3SF5874-4A. is an AS-Interface front panel module designed to bring command devices — pushbuttons, selector switches, pilot lights — onto an AS-i bus without running individual control wires back to the cabinet. It accepts 22 mm round or square operator units and provides four control points, wired via an insulation displacement connection (IDC) system that punches down the flat AS-i cable directly, no stripping or screw terminals.
What the ratings mean for fit
The 22 mm mounting diameter matches the standard panel cutout for industrial pushbuttons, selector switches, and pilot lights across brands — any 22 mm operator from Siemens or a third party fits this module. The round installation opening accepts both round and square bezels, so you're not locked into one trim style. The module does not carry an emergency-stop function and does not provide positive opening of the NC contacts — that means it is not rated for safety circuits where a mechanically forced break is required. For guarding or e-stop applications, you would need a separate safety-rated AS-i module or a hardwired safety relay.
Deployment context
This module mounts in a panel or enclosure door via the 22 mm cutout and fastens vertically or horizontally. The insulation displacement system means you run the AS-i flat cable through the module and press it closed — no stripping, no terminal blocks, no daisy-chain wiring. That saves panel-build time and reduces connection points that can vibrate loose on a conveyor line or pump skid. The module has no integral light source and no optional light-source extension, so any pilot-light function must come from the operator unit itself, not from this base module.