E3JK Photoelectric Senors with Built-in Power Supply The E3JK series of photoelectric sensors from Omron have a built in power supply. This series of photoelectric sensors have a high power and visible red LED for all models enabling easy alignment and long sensing distance. Relay output (all voltage) Red LED that makes the spot visible Large indicators that can be seen even from a distance Improved operability, enlarged sensitivity adjuster and operation selector ABS housing