OMRON E3Z-G81 Grooved (U-Type) Photoelectric Sensor

Full Product Name: Grooved photoelectric switch with built-in amplifier, 1 optical axis, PNP output

✅ Model Code Explanation

E3Z: Series of photoelectric sensors with built-in amplifier

G: Grooved / U-type through-beam

8: PNP output (6 = NPN)

1: Single optical axis (2 = Dual optical axis)

Suffix:

2M: Fixed cable, 2m length (Most common model in China)

-M3J 0.3M: M8 4-pin pre-wired connector, 0.3m lead

-M1J-1 0.3M: M12 4-pin pre-wired connector, 0.3m lead

📋 Core Technical Specifications

🛠️ Application Scenarios

The grooved photoelectric sensor triggers signal when an object blocks the infrared beam inside the U-slot:

Conveyor material counting & position detection

Home position / limit detection for cylinders and slides

Door switch detection for elevator and automation equipment

Label detection, notch detection for disc parts

High-speed sorting and stepping positioning (1ms response suitable for high-speed applications)

📌 Wiring Instruction (E3Z-G81 2M cable version, Brown/Blue/Black/White)

1. Brown: DC+ 12~24V
2. Blue: DC0V
3. Black: PNP signal output wire
4. White: Mode selection wire (Light ON / Dark ON)

White wire connected to DC+: Dark ON (Light-blocked ON, normally closed logic); White wire floating: Light ON (Light-received ON, normally open logic)

⚠️ Model Selection & Troubleshooting Key Points

1. Distinguish NPN/PNP: E3Z-G61 = NPN; E3Z-G81 = PNP. PLC input module polarity must match.
2. Dust and debris accumulated in slot will block infrared light and cause false triggering; IP64 rating, NOT suitable for heavy water spray environments.
3. Detected object must be opaque; transparent plastic or thin translucent sheets cannot be reliably detected.
4. Dual optical axis model: E3Z-G82, used to prevent false detection of single optical axis, for dual-position signal acquisition.

🔁 Replacement Reference

Domestic alternative: U-groove photoelectric sensor, 25mm slot width, PNP, DC24V, 1ms response (compatible with OMRON E3Z-G series, brands like Shenwu, Senso etc.)

Interchange within series: E3Z-G81 (Single axis PNP) ↔ E3Z-G61 (Single axis NPN); E3Z-G82 (Dual axis PNP)

HS Code Reference

85414090 (Photosensitive semiconductor device, photoelectric sensor, for customs declaration only, subject to customs final verification)

OMRON E3Z-G81 Grooved Photoelectric Sensor Installation Guide

Applicable Models: E3Z-G81 (2m cable), E3Z-G81-M3J (M8 0.3m pre-wired connector, PNP single-axis grooved photoelectric)

25mm groove width, built-in amplifier, IP64, DC12~24V, Light ON / Dark ON selectable

1. Pre-installation Inspection
2. Unboxing Verification

Confirm model E3Z-G81; Inspect housing, transmitter/receiver windows inside slot for scratches, damage and oil contamination

Check cable integrity; Confirm orange operation indicator is intact

2. Environment Check

Ambient temperature: -25℃ ~ +55℃, no icing or condensation

Prohibited: Direct sunlight / strong incandescent light on optical path, corrosive gas, continuous water spray, heavy dust accumulation, heavy vibration and shock

Avoid routing signal cable closely in parallel with inverter, contactor and power cables (EMI causes false triggering)

3. Workpiece Verification

Sensing object: Opaque solid, minimum detectable size ≥φ1.5mm; Thin transparent sheets cannot be reliably sensed

Workpiece moving direction: Pass perpendicularly through the optical axis of U-slot, avoid sweeping the beam diagonally

2. Mechanical Installation Procedure

2.1 Mounting Method

E3Z-G81 housing has built-in M3 mounting holes, fixed with M3 screws

Recommended tightening torque: ≤0.5 N·m. Excessive torque may crack ABS housing. Never strike sensor body with hammer; it will damage IP seal and optical path.

Optional OMRON E39 mounting bracket for rack installation

2.2 Mounting Position & Optical Path Requirements (Critical)

1. Workpiece must fully pass through the optical axis at center of U-slot and completely cut off infrared beam when blocked
2. Keep clearance between workpiece and slot wall. Do not scratch transmitter/receiver window to avoid lens scratch and dust buildup
3. Workpiece thickness: Opaque material is acceptable; Workpiece entering/exiting slot must not impact sensor housing
4. Multiple grooved sensors mounted side by side: Keep sufficient spacing to prevent mutual optical interference
5. Sensor may be mounted directly on metal frame; U-groove type is immune to reflection from nearby metal surfaces.

✅ Installation Verification: Orange indicator toggles when workpiece enters slot to block beam, and recovers after workpiece exits.

2.3 Cable Installation Specification

1. Cable bending radius ≥ 4 × cable outer diameter; Avoid repeated bending near cable root; Max cable tension ≤50N. Never pull sensor body by cable force
2. Separate signal cable and power cable into different conduits, not in same trunking; If parallel routing is unavoidable, maintain ≥10cm spacing
3. Cable extension: Extended wire cross-section ≥0.3mm², total length ≤100m; Insulate terminals properly
4. Connector version (E3Z-G81-M3J): Do not pull cable during M8 connector plug/unplug; Tighten thread fully; Inspect connector seal regularly
5. Electrical Wiring (Perform under power OFF! Wiring with power ON is prohibited)

3.1 Cable outlet model (E3Z-G81, 4-core: Brown, Blue, Black, White)

PNP output: High level active; PLC input module requires sourcing input.

3.2 M8 Connector Model E3Z-G81-M3J (4-pin)

Pin1: Brown DC+; Pin3: Blue DC-; Pin4: Black Output; Pin2: White Mode Selection (can be left unused)

3.3 Pre-power Check

Power supply DC12~24V, ±10%; Do NOT connect AC220V

Confirm power polarity without reverse connection; Sensor has built-in reverse polarity & short-circuit protection, but wiring verification is still required

Load (PLC input) wired correctly; Never short output directly

4. Power-on Commissioning Steps
5. Complete mechanical fixing and wiring with power OFF, double check
6. Power on, slot unblocked (beam passes):

Light ON (white wire floating): Beam received, orange LED ON, PNP output activated

Dark ON (white wire connected to +24V): Beam received, orange LED OFF, output deactivated

3. Insert opaque workpiece into slot to block optical path:

Light ON: Beam blocked, indicator OFF, output deactivated

Dark ON: Beam blocked, indicator ON, PNP output activated

4. Test workpiece in/out repeatedly to verify stable indicator and PLC signal
5. If signal jitters, check: ① Workpiece fully blocks beam; ② Dust on window; ③ EMI from power cable; ④ Loose mounting and vibration
6. Maintenance
7. Regular cleaning of transmitter and receiver windows inside U-slot: Wipe gently with lint-free cloth and anhydrous alcohol. Hard brush and strong solvent (acetone, thinner) are forbidden; they corrode ABS and optical lens
8. Periodic inspection: Loose screws, damaged cable jacket, water/oil ingress at connector
9. Increase cleaning frequency for heavy dust environment
10. Prohibited: Direct water or oil spray onto sensor body
11. Installation Taboos & Safety Notes
12. Not for explosive hazardous area
13. Cannot be immersed or continuously splashed; IP64 only protects against splashing water
14. Do not touch internal infrared LED by hand
15. High vibration equipment: Add lock washers and retorque screws periodically
16. Never unplug cable or disassemble sensor when powered ON
17. Quick Troubleshooting for Common Installation Issues

OMRON E3Z-G81 Grooved Photoelectric Sensor with Built-in Amplifier

Complete Product Manual (English, sourced from OMRON official E3Z-G datasheet)

Applicable Models: E3Z-G81 2M (2m fixed cable), E3Z-G81-M3J (M8 4-pin connector, 0.3m lead)

1. Product Overview

E3Z-G81 is U-shaped grooved through-beam photoelectric sensor with built-in amplifier, single optical axis, PNP open-collector output; groove width 25mm. Detects objects when opaque material blocks infrared beam inside U-slot. Switchable between Light ON / Dark ON, response time ≤1ms, suitable for high-speed positioning, counting and home detection.

Series Classification:

E3Z-G81: Single axis PNP; E3Z-G82: Dual axis PNP

E3Z-G61: Single axis NPN; E3Z-G62: Dual axis NPN

2. Model Composition

E3Z-G81

E3Z: Photoelectric sensor series with built-in amplifier

G: Grooved U-slot type

8: PNP output (6=NPN)

1: Single optical axis (2=Dual optical axis)

Suffix:

2M: Fixed cable, length 2m (standard version)

-M3J: M8 4-pin pre-wired connector, 0.3m lead

3. Rated Specifications & Performance

4. Dimension Outline (Unit: mm)

U-shaped body, M3 mounting holes; 25mm slot opening, two built-in M3 screw holes.

Recommended tightening torque: ≤0.5 N·m. Excessive torque may crack housing.

Optional accessory: E39 mounting bracket (sold separately)

5. Wiring Definition

5.1 Cable Outlet Version E3Z-G81 2M (4-core: Brown, Blue, Black, White)

5.2 M8 Connector Version E3Z-G81-M3J (4-pin)

✅ Operation Logic

1. Light ON (White wire floating, factory default)

Beam unblocked (no obstruction): Orange LED ON, PNP output ON (High level);

Beam blocked: Orange LED OFF, output OFF.

2. Dark ON (White wire connected to DC+)

Beam unblocked (no obstruction): Orange LED OFF, output OFF;

Beam blocked: Orange LED ON, PNP output ON (High level).

6. Installation Requirements
7. Fix with M3 screws, add lock washer, torque ≤0.5N·m. Do not strike sensor body.
8. Workpiece passes perpendicularly through U-slot optical axis; workpiece movement must not scratch or impact transmitter/receiver window.
9. Keep enough spacing for multiple grooved sensors mounted side by side to prevent mutual optical interference.
10. Separate signal cable and power cable; ≥100mm spacing if parallel routing is mandatory. Cable minimum bending radius ≥4 × cable OD; Max cable tension ≤50N.
11. Installation environment: Avoid direct strong light on optical path, corrosive gas, continuous water spray and heavy dust accumulation.
12. Commissioning Steps
13. Wire with power OFF, confirm no AC220V miswiring, check polarity.
14. Power on, slot unobstructed, observe orange indicator to verify operation mode.
15. Insert opaque workpiece into slot to cut beam, observe indicator state flip and verify PLC input signal.
16. Repeat workpiece in/out test to confirm stable signal without jitter.
17. Maintenance
18. Regular cleaning of U-slot transmitter and receiver windows: Wipe gently with lint-free cloth dipped in anhydrous alcohol. Acetone, thinner and other strong solvents are forbidden; hard material scratch on lens is prohibited.
19. Regular inspection for loose mounting screws, damaged cable jacket and connector seal integrity.
20. Increase cleaning frequency for dusty environment. Do not spray water or oil directly onto sensor.
21. Safety Notes
22. This product cannot be used in explosive hazardous areas; IP64 only protects splash water and cannot resist immersion.
23. Do NOT plug/unplug cable or disassemble sensor while powered ON.
24. Load current of output must not exceed 100mA, otherwise internal circuit damage occurs.
25. Do not touch infrared LED emitting surface by hand.
26. This sensor is for general industrial detection, cannot be directly used as safety protective device (safety light curtain).
27. Troubleshooting Table

11. Accessories, Alternatives & Customs Reference

Interchange within series: E3Z-G81 (Single axis PNP) ↔ E3Z-G61 (Single axis NPN); E3Z-G82 Dual axis PNP

Domestic alternative: Groove photoelectric sensor, 25mm slot width, PNP output DC24V, response ≤1ms

HS Code Reference: 85414090 (Photosensitive semiconductor device, for customs declaration only, subject to customs final verification)

If needed, I can further provide:

1. A4 one-page printable condensed English manual
2. Wiring schematic for E3Z-G81 to Siemens PLC sourcing input