OPTEX Z2R-400N Retro-reflective Photoelectric Sensor

Z2: Z2 series economical built-in amplifier photoelectric sensor

R: Retro-reflective type (requires matching reflector)

400: Maximum sensing distance of 4 m

N: NPN output, cable type (corresponding connector version: Z2R-400CN4)

Core Specifications

Product Features

1. Red light source with visible light spot for easy alignment during commissioning; capable of detecting semi-transparent objects, ideal for blocking detection on production lines
2. Switchable light-on / dark-on operation mode (NO/NC)
3. IP67 dustproof and waterproof, vibration and shock resistant, suitable for factory automation and conveyor lines
4. Low power consumption, standard square housing for universal mounting
5. Stable indicator light to judge mounting offset and signal margin

Typical Application Scenarios

Object presence / position detection on conveyor lines

Obstacle detection for automatic doors and gates

Packaging machinery, logistics sorting, workpiece counting on automated lines

Detection of transparent films and plastic bottles (retro-reflective type offers obvious advantages for transparent materials)

Alternative Model Comparison

Z2R-400P: Same specifications, PNP cable type

Z2R-400CN4: NPN, M8 connector type

Z2R-400CP4: PNP, M8 connector type

Wiring Description (4-core Cable)

Brown: DC+ 10~30 V

Blue: 0 V

Black: Signal output (NPN)

White: Operation mode selection (Light-ON / Dark-ON)

OPTEX Z2R-400N Application Case Summary

Recap of key features: Retro-reflective type, sensing range 0.01~4 m, NPN output, IP67, red light source, response ≤500 μs. Reflector V-61 is mandatory. Suitable for stations within 4 m where wiring is only required on the sensor side; compatible with solid workpieces and semi-transparent materials.

Case 1: Box Presence / Position Detection on Logistics Conveyor (Material Handling)

Industry: E-commerce warehousing, packaging conveyor lines

Purpose: Box / tote position confirmation, missing material alarm, product counting on belt conveyors

Installation: Sensor mounted on one side of the conveyor; reflector fixed on the opposite frame. When a box passes and blocks the light beam, an NPN signal is sent to PLC.

Selection Justification: 4 m sensing distance accommodates wide conveyors; wiring only needed for sensor, reflector requires no wiring to reduce installation cost; IP67 withstands dust in production environment; visible red light spot for fast on-site alignment.

Process Logic: Dark-ON. Count is triggered when box passes; continuous light reception without workpiece triggers empty material alarm.

Case 2: Counting & Position Detection on Tire Production Line (Official OPTEX Reference Case)

Industry: Rubber tire manufacturing

Purpose: Counting and position signal for tires after vulcanization, preventing stacking

Installation: Sensor and reflector installed opposite across the belt; tire body blocks light beam. Retro-reflective principle is less affected by workpiece color variation for large rubber parts.

Advantages: 500 μs response time suitable for high-speed conveying; adjustable sensitivity via single-turn potentiometer to reduce false triggering in dusty production environments.

Case 3: Packaging Machinery – Transparent PET Bottle & Film Detection

Industry: Food, daily chemical filling lines

Purpose: Presence detection of transparent PET bottles and plastic films (diffuse sensors often fail to detect transparent parts)

Notes: Z2R-400N is standard retro-reflective sensor, supports semi-transparent material detection. Fully transparent glass requires dedicated transparent-object photoelectric sensor such as ZR-Q series. When bottle blocks light beam, return light from reflector is cut off and sensor outputs signal.

Precautions: Thin transparent films require fine potentiometer adjustment to lower sensitivity and avoid missing detection caused by light penetration. Reflector needs regular cleaning to prevent contamination by liquid splashes.

Case 4: Obstacle Detection for Automatic Doors / Gates

Industry: Automated warehouse, workshop rolling shutters, AGV channel barriers

Purpose: Obstacle detection as an alternative to safety light curtains, anti-pinch protection

Installation: Sensor mounted on one side of channel, reflector on opposite column. Human / material intrusion blocks light beam to stop door movement.

Advantages: 4 m range meets most channel width requirements; standard square housing compatible with mounting bracket BEF-W100-B; wide temperature range -25~+55℃ adapts to hot and cold workshop environments.

Case 5: Work Tray & Fixture Return Line Position Confirmation

Industry: 3C, automotive component assembly lines

Purpose: Position signal for circulating work trays, pre-confirmation signal for robot pick-and-place operation

Installation: Sensor mounted on side of frame, reflector fixed on opposite bracket. Tray in position blocks light beam and sends “tray ready” signal to PLC to enable robot operation.

Advantages: Light-ON / Dark-ON switchable via white wire connection to match different equipment logic; NPN output compatible with Japanese PLC input modules.

Case 6: Discharge Counting for Carton Sealing & Strapping Machines

Industry: Post-packaging equipment

Purpose: Count finished packaged products and missing package alarm

Working Condition: Heavy vibration, paper scraps and dust on equipment; IP67 protection against vibration and impact; large light spot maintains stable detection with minor workpiece offset.

Selection & On-site Operation Notes

1. Max effective distance is 4 m, not applicable beyond this range. Signal margin is more sensitive to dust at longer distances.
2. Retro-reflective principle: Reflector shall not be covered by oil or dust for long periods, regular maintenance required.
3. Use caution for highly reflective workpieces (polished metal): workpiece surface reflection may replace reflector and cause false triggering. For such scenarios, use diffuse or background suppression photoelectric sensors instead.
4. Not recommended for fully transparent glass. OPTEX ZR-Q series dedicated transparent-object photoelectric sensor is preferred.

OPTEX Z2R-400N BOM List + PLC Wiring Example

1. BOM List (Single Station)

Optional Replacement: If M8 connector version is required, replace sensor with Z2R-400CN4, matched with M8 4-core straight / angled cable.

2. Wiring Diagram (Z2R-400N 4-core Cable)

PLC Wiring Key Points (Japanese Sink PLC, Mitsubishi FX / Omron)

1. Power supply: DC24V power supply feeds sensor; power negative connected to PLC COM terminal
2. Signal circuit: Sensor black output wire → PLC input terminal X
3. Recommended mode: White wire to 0V → Dark-ON. PLC receives ON signal when workpiece blocks light, suitable for position detection and counting.
4. Load note: Sensor max output current is 100 mA. PLC input draws tiny current and can be directly connected. Do NOT drive solenoid valve directly.
5. On-site Commissioning Procedure (Dark-ON Mode, for Transparent & Ordinary Workpieces)
6. Complete wiring and power on. Align light beam to reflector until green stable indicator remains lit (good light alignment).
7. Turn potentiometer clockwise to maximum sensitivity.
8. Place test workpiece and verify change of orange operation indicator.
9. Fine-tune potentiometer: Gradually reduce sensitivity to ensure stable triggering when workpiece blocks light and avoid false triggering caused by workpiece surface reflection.

Commissioning Tip for Transparent Film / PET Bottle: Lower sensitivity to reduce missed detection caused by light penetration.

4. Program Logic Example (Mitsubishi FX Ladder Description)

Setup: X0 connected to Z2R-400N black signal wire (Dark-ON)

1. Position Detection: `X0 ON` → Workpiece in position, activate Y0 position indicator
2. Counting: Rising edge of X0 triggers counter C0, increment count by 1 for each workpiece
3. Empty Material Alarm: Trigger missing package alarm Y1 when X0 stays OFF longer than preset time
4. Additional Notes
5. Mount reflector V-61 with surface perpendicular to sensor beam; inclination reduces effective sensing distance.
6. For dusty working conditions, reserve maintenance access for reflector cleaning; oil contamination leads directly to light path failure.
7. Not recommended for polished metal workpieces. Workpiece reflection may mimic reflector and cause false reading. Use background suppression photoelectric sensor for this case.
8. Operating temperature: -25~55℃. Heat insulation protection required for high-temperature baking environment.
9. Z2R-400N VS Z4R-400N Application Comparison