Omron E3Z-T81 2M Photoelectric Sensor
Omron E3Z-T81 2M is a through-beam photoelectric sensor designed for object sensing across a specified distance of 15 m. The sensing arrangement uses the E3Z-T81-L emitter and E3Z-T81-D receiver, with an 870 nm infrared LED establishing the optical path between them. The PNP output communicates the switching state to compatible machine-control circuitry, while selectable Light-ON and Dark-ON operation supports different switching requirements. The sensor operates from 12 to 24 VDC and includes 2 m pre-wired cables for electrical connection. Total current consumption is specified at 35 mA maximum, while response time is 1 ms maximum. Within the E3Z Series, the E3Z-T81 2M provides fixed wiring within the 15 m PNP through-beam sensor range across Omron Industrial Products.

| Brand | Omron |
| Product | Photoelectric Sensors |
| Model Number | E3Z-T81 2M |
Omron E3Z-T81 2M Photoelectric Sensor – Technical Specifications
| Specification | Value |
|---|---|
| Sensing Method | Through-beam |
| Sensing Distance | 15 m |
| Emitter Number | E3Z-T81-L 2M |
| Receiver Number | E3Z-T81-D 2M |
| Standard Sensing Object | Opaque: 12-mm dia. min. |
| Light Source | Infrared LED (870 nm) |
| Power Supply Voltage | 12 to 24 VDC |
| Output Configuration | PNP |
| Connection Method | Pre-wired 2 M cable |
| Current Consumption | 35 mA max. (Emitter: 15 mA max., Receiver: 20 mA max.) |
| Control Output | Load power supply voltage: 26.4 VDC max., Load current: 100 mA max. Residual voltage: Load current of less than 10 mA: 1 V max. Load current of 10 to 100 mA: 2 V max. |
| Operation Mode | Light-ON/Dark-ON selectable |
| Response Time | Operate or reset: 1 ms max. |
| Sensitivity Adjustment | One-turn adjuster |
| Indicators | Operation indicator (orange), Stability indicator (green), Through-beam Emitter has power indicator (orange) only. |
| Ambient Illumination | Incandescent lamp: 3,000 lx max. Sunlight: 10,000 lx max. |
| Ambient Temperature Range | Operating: −25 to 55°C, Some connector models: −40°C to 55°C, Storage: −40 to 70°C (with no icing or condensation) |
| Ambient Humidity Range | Operating: 35% to 85%, Storage: 35% to 95% (with no condensation) |
| Insulation Resistance | 20 MΩ min. at 500 VDC |
| Dielectric Strength | 1,000 VAC, 50/60 Hz for 1 min |
| Vibration Resistance | Destruction: 10 to 55 Hz, 1.5 mm double amplitude for 2 hours each in X, Y, and Z directions |
| Shock Resistance | Destruction: 500 m/s2 3 times each in X, Y, and Z directions |
| Protection Circuits | Reversed power supply polarity protection, Output short-circuit protection, and Reversed output polarity protection |
| Degree Of Protection | IEC, IP67 |
| Material | PBT (polybutylene terephthalate), Modified polyarylate |
| Weight | Approx. 30 g |
The Omron E3Z-T81 2M Photoelectric Sensor uses through-beam sensing across a specified distance of 15 m. The sensing arrangement includes the E3Z-T81-L emitter and E3Z-T81-D receiver, with an 870 nm infrared LED establishing the optical beam between them. An opaque target of 12 mm diameter minimum is specified. The PNP output supports a load supply voltage up to 26.4 VDC and load current up to 100 mA. The units operate from 12 to 24 VDC and consume 35 mA maximum in total, with 15 mA maximum specified for the emitter and 20 mA maximum for the receiver. Light-ON or Dark-ON operation is selectable, while operate or reset time is 1 ms maximum. A one-turn adjuster supports setup, and 2 m pre-wired cables provide fixed electrical connection.
For an Omron PNP through-beam sensor requiring a 15 m sensing distance and 2 m fixed wiring, the relevant model is the E3Z-T81. Operation and stability indicators provide visual status, while the emitter includes a power indicator. Operating temperature is specified from -25 to 55°C, with storage from -40 to 70°C under the supplied conditions. Reversed power-supply polarity protection, output short-circuit protection, and reversed output-polarity protection are listed. PBT and modified polyarylate are specified among the materials. Its fixed cable arrangement provides a direct wiring option for compatible control systems. For the same E3Z-T81 sensing arrangement with longer 5 m pre-wired cables, see E3Z-T81 5M.

