Autonics BW20-12P 12 Beam PNP General Purpose Area Sensor

A. Product Overview

The Autonics BW20-12P Area Sensor is an industrial multi beam photoelectric sensor designed to detect objects passing through a defined sensing area.

Unlike a conventional single point photoelectric sensor, the BW20-12P uses multiple infrared beams between an emitter and receiver. This creates a wider detection zone and allows the sensor to detect objects even when their exact position changes within the sensing area.

It is especially suitable for conveyor systems, packaging machinery, assembly lines, material handling systems, and automated machines where reliable presence detection is required.

Key Specifications

• Brand: Autonics
• Model: BW20-12P
• Product Type: Area Sensor
• Detection Method: Through Beam
• Number of Optical Axes: 12
• Optical Axis Pitch: 20 mm
• Sensing Height: 220 mm
• Total Sensor Length: Approximately 240 mm
• Sensing Distance: 0.1 to 7 m
• Light Source: Infrared LED
• Wavelength: Approximately 850 nm
• Minimum Detectable Object: Approximately 30 mm diameter opaque object
• Control Output: PNP Open Collector
• Operation Mode: Light ON
• Power Supply: 12 to 24 VDC
• Response Time: Maximum 10 ms
• Protection Rating: IP65
• Operating Temperature: Approximately minus 10°C to 55°C
• Storage Temperature: Approximately minus 20°C to 60°C
• Connection Type: Cable Connector Type
• Connector Type: M12
• Housing Material: Aluminum

B. Working Principle

The Autonics BW20-12P through beam area sensor works using an emitter and receiver installed opposite each other.

The emitter sends multiple infrared light beams toward the receiver.

When there is no object between the emitter and receiver, the light beams reach the receiver normally.

When an opaque object enters the sensing area, one or more beams are interrupted. The receiver detects this interruption and changes the sensor output.

The working sequence can be understood as:

Emitter sends infrared beams → Receiver monitors beams → Object enters sensing area → Beams are blocked → Sensor detects object → PNP output changes → PLC or controller receives signal

Because the BW20-12P has 12 optical axes, it can monitor a much larger area compared with a standard single beam photoelectric sensor.

A. Through Beam Detection

The emitter and receiver are installed separately and face each other.

The object is detected when it passes between the two units and interrupts the infrared light.

B. Multiple Optical Axes

The sensor uses 12 separate optical axes with 20 mm spacing.

This creates a detection zone with approximately 220 mm sensing height.

C. PNP Output

The BW20-12P uses a PNP open collector output.

The output can be connected to compatible PLC inputs, industrial controllers, counters, and automation systems.

C. Why Is the Autonics BW20-12P Used?

The BW20-12P is used when an industrial application requires detection across a wider area instead of detection at only one fixed point.

Wide Area Object Detection

A conventional photoelectric sensor normally detects objects across one optical beam.

The BW20-12P uses 12 beams, allowing it to monitor a significantly larger sensing area.

Conveyor Object Detection

The sensor can detect products travelling on conveyors even when their position or height changes slightly.

Typical examples include:

• Cartons
• Boxes
• Packages
• Containers
• Industrial components
• Finished products

Packaging Machine Detection

Packaging machinery can use the BW20-12P to confirm whether products or packages are present before the next machine operation begins.

Product Counting

The sensor output can be connected to a PLC or counter for production counting applications.

Missing Product Detection

The sensor can help identify whether a product is missing from a conveyor or production line.

Material Flow Monitoring

The BW20-12P can detect whether material is passing through a specific section of automated equipment.

Production Line Monitoring

The sensor can provide detection signals for:

• Product counting
• Presence confirmation
• Process sequencing
• Conveyor control
• Alarm generation
• Machine interlocking
• Production monitoring

Irregular Object Detection

Objects may vary in shape, size, or vertical position.

A multi beam area sensor provides a larger detection zone, improving detection reliability compared with a single beam sensor.

D. Suitable Buyers

The Autonics BW20-12P 12 Beam PNP Area Sensor is suitable for industrial manufacturers, automation companies, OEM machine builders, and maintenance departments.

Industrial Automation Companies

Automation integrators can use the BW20-12P with PLC systems for object detection, counting, sequencing, and machine control.

Packaging Machine Manufacturers

Packaging equipment manufacturers can use the sensor for carton, packet, bottle, container, and product presence detection.

Conveyor System Manufacturers

The sensor can be used for product detection, conveyor monitoring, accumulation control, and material flow applications.

Special Purpose Machine Manufacturers

SPM manufacturers can integrate the BW20-12P into machines requiring wide area object detection.

Material Handling Companies

Automated material handling systems can use the sensor to monitor products moving between conveyor sections.

Warehouse Automation Companies

Warehouse and logistics automation systems can use area sensors for object presence and movement detection.

Assembly Line Manufacturers

The sensor can help confirm whether components or products are present at specific stages of an assembly process.

Control Panel Manufacturers

Panel builders can integrate the PNP output into compatible PLC systems and industrial controllers.

Factory Maintenance Departments

Maintenance engineers can use the BW20-12P as a replacement where the machine requires:

• 12 optical axes
• 20 mm optical pitch
• 220 mm sensing height
• 0.1 to 7 m sensing distance
• PNP output
• 12 to 24 VDC supply

FAQ

1. What is the Autonics BW20-12P?

The Autonics BW20-12P is a through beam area sensor with 12 optical axes designed for detecting opaque objects across a defined sensing area.

2. What is the sensing distance of BW20-12P?

The sensing distance is approximately 0.1 to 7 m.

3. How many optical axes does BW20-12P have?

The sensor has 12 optical axes.

4. What is the optical axis pitch?

The optical axis pitch is 20 mm.

5. What is the sensing height?

The sensing height is approximately 220 mm.

6. What is the total sensor length?

The total sensor length is approximately 240 mm.

7. Is BW20-12P an NPN or PNP sensor?

The BW20-12P provides a PNP open collector output.

8. What power supply does BW20-12P require?

It operates on 12 to 24 VDC.

9. What sensing method does BW20-12P use?

It uses a through beam photoelectric sensing method.

10. What light source is used?

The sensor uses an infrared LED with approximately 850 nm wavelength.

11. What is the minimum detectable object size?

The minimum detectable target is approximately a 30 mm diameter opaque object.

12. Can BW20-12P detect transparent objects?

The sensor is primarily intended for opaque object detection. Transparent materials may require a different sensor depending on the application.