Sensor overview
The Siemens 3RG7640-3HC00 is a SIMATIC PXO210 M18S diffuse sensor with energetic straight optics. It runs on 10-30 V DC, provides a 500 mm sensing range, and switches via an NPN antivalent output rated for 150 mA. The M12 4-pole connector and IP67 enclosure make it a straightforward swap on a line where the mounting and wiring are already in place.