Sensor fit for a detection line
The E3FA-RN21 is an Omron photoelectric sensor that emits a visible LED light, making it straightforward to align on a conveyor or machine guard — the beam is visible to the naked eye during setup, so you can confirm the optical path without a separate alignment tool. It sits in the Photoelectric Sensors category, which means it is designed for non-contact object detection in automated lines — think part-present sensing on a packaging line, or confirming a workpiece has cleared a press station before the next cycle starts.
Peer cross-reference — E3S-CD67 as a functional second-source
Both sit in the same category, so if you have a panel specified around the E3S-CD67 and need a second-source, the E3FA-RN21 is a candidate — but confirm the mounting thread, sensing range, and output type against your application before committing the BOM line.