The Siemens 3RG7211-6MC61 is a SIMATIC PXO620 K80 retro reflective photoelectric sensor with a built-in polarisation filter. It operates on universal voltage 20-230V AC/DC and provides a relay changeover contact (C-contact, antivalent) with a sensing range up to 12 metres. The housing measures 83x61x25 mm, terminates via a PG11 gland with a 5-pole connection, and carries an IP67 rating. An integrated timer is adjustable from 0.1 to 10 seconds.
The polarisation filter rejects false reflections from shiny targets, so this sensor handles glossy or mirrored surfaces that would fool a standard retro reflective unit. The 12-metre range covers long conveyor spans or warehouse aisles. Universal supply (20-230V AC/DC) simplifies wiring in mixed-voltage panels — no separate DC supply needed. The relay output (C-contact) gives both NO and NC in one package, useful for fail-safe interlocking. IP67 lets it live in washdown or dusty areas without an extra enclosure. The built-in timer (0.1-10 s) can stretch or delay the output pulse, saving an external timing relay.