Omron E3Z-R81 5M Photoelectric Sensor
Omron E3Z-R81 5M is a PNP retro-reflective photoelectric sensor with an M.S.R. function and a specified sensing range from 100 mm to 4 m. Its 670 nm red LED directs light toward the reflector, while the PNP output transfers the switching state to compatible PLC and machine-control inputs. Selectable Light-ON and Dark-ON operation supports different control requirements. The sensor operates from 12 to 24 VDC and includes a 5 m pre-wired cable for extended electrical connection. Current consumption is specified at 30 mA maximum, while response time is 1 ms maximum. The longer cable differentiates this version from shorter fixed-wiring configurations. Within the E3Z Series, the E3Z-R81 5M provides longer fixed wiring within the 4 m PNP retro-reflective sensor range across Omron Automation Sensors.

| Brand | Omron |
| Product | Photoelectric Sensors |
| Model Number | E3Z-R81 5M |
Omron E3Z-R81 5M Photoelectric Sensor – Technical Specifications
| Specification | Value |
|---|---|
| Sensing Method | Retro-reflective with M.S.R. function |
| Shape | Square |
| Sensing Distance | 100 mm to 4 m |
| Power Supply Voltage | 12 to 24 VDC |
| Output Configuration | PNP |
| Connection Method | Pre Wired Cable, 5m Length |
| Current Consumption | 30 mA max. |
| Light Source (Wavelength) | Red LED (670 nm) |
| Operation Mode | Light-ON/Dark-ON selectable |
| Response Time | 1 ms max. |
| Degree Of Protection | IEC: IP67 |
| Material | Polybutylene terephthalate (PBT) |
| Material Lens | Denatured Polyarylate |
| Features | Transparent detection |
| Weight | 65g |
The Omron E3Z-R81 5M Photoelectric Sensor uses retro-reflective sensing with an M.S.R. function across a specified range from 100 mm to 4 m. A 670 nm red LED supplies the optical source directed toward the reflector, while the PNP output communicates the switching state to compatible PLC and machine-control inputs. The sensor operates from 12 to 24 VDC and consumes up to 30 mA. Selectable Light-ON and Dark-ON operation allows the output behavior to match different control requirements, while response time is specified at 1 ms maximum. A 5 m pre-wired cable provides extended fixed wiring from the sensing position to associated control equipment. PBT is listed for the case, while denatured polyarylate is specified for the optical material.
For an Omron PNP retro-reflective sensor requiring an M.S.R. function and extended pre-wired connection, the relevant model is the E3Z-R81. Its 100 mm to 4 m sensing range supports reflector placement across the stated span, while 12 to 24 VDC operation allows connection with compatible industrial control circuits. Current consumption is specified at 30 mA maximum, and the 1 ms response supports quick switching. The 5 m cable is useful where the machine-side connection is positioned farther from the sensing point than with shorter cable versions. Its characteristics also support requirements for an Omron 4 m PNP sensor and Omron pre-wired retro-reflective sensor. For another E3Z-R81 version using a shorter 2 m pre-wired cable, see E3Z-R81 2M.


