The Siemens 3RG7212-6MC17 is a SIMATIC PXO630 K80 thru-beam sensor receiver — the receiving half of a photoelectric pair. It's rated for UC 20-230 V supply, with a 50 m sensing range, relay output (C-contact antivalent), and an onboard timer adjustable from 0.1 to 10 s. The housing is 83x61x25 mm, sealed to IP67, with a PG11 cable gland and 5-pole termination.
The universal voltage supply (UC 20-230 V) covers both AC and DC control circuits without needing a separate power module — handy for retrofit into existing panels where the control voltage may vary. The antivalent relay contact gives both normally-open and normally-closed outputs from the same switching event, which simplifies wiring to two separate control inputs. The adjustable timer (0.1-10 s) can be set for on-delay or off-delay depending on the application, useful for conveyor gap control or part-present gating.