What it is and what it does
The Siemens 3RG7641-0CD00 is a SIMATIC PXO220 M18S retro-reflective photoelectric sensor with polarized optics. It detects objects by reflecting its own beam off a separate reflector — the polarization filter cuts false triggers from shiny surfaces. Rated 10-30V DC, PNP output, light-on switching, 150mA max load. Cable exit: 2m PUR, 4x0.34mm², IP67 enclosure.
What the ratings mean for fit
The 10-30V DC supply covers standard 24V industrial control loops. PNP light-on output means the signal goes high when the beam is received — typical for detecting a reflector presence. The 2m PUR cable is oil- and abrasion-resistant, suited for drag chains or washdown zones. IP67 lets it live in wet or dusty enclosures without a secondary housing.