News & Events

Download full pdf

• Click here to download a full pdf of the current issue (2,75 MB)

Automation Today

• Overview
  Efficiency - Your key to competitiveness

Product focus

• A round up of the latest Rockwell Automation products and services - 3-2006
• Servo drive technology available in expanded power ranges
• Ideal batch solutions for smaller operations
• Drives management goes wireless

Add more flexibility and reliability

The new Allen-Bradley 44B photoelectric sensor, from Rockwell Automation, with adjustable background and foreground suppression, is intended for industrial applications requiring the reliable detection of targets close to a surface that must be ignored by the sensor.

Unlike standard diffuse-style sensors, the new sensor incorporates a dual-receiver optical system to actively see both the target and background areas – allowing the sensor to suppress any background reflections.

The 44B photoelectric sensor is available in two sensing modes with a common optics system. The difference between the two lies in their operation. Both sense modes will actively see the background condition using a second internal receiver, however, the background suppression sense mode will change its output state when it sees reflected light from the target.

In contrast, the foreground suppression sense mode will use the background as a reflector and change its output state when a target blocks this reflector. The background suppression sense mode is best suited for the detection of light targets against a less reflective background. An application example is the detection of missing bottle caps. The sensor will “see” the bottle cap by the reflected light from the cap while ignoring the bottle.

Foreground suppression should be used when looking at a dark or irregularly shaped target against a highly reflective background. This is ideal for the detection of products on a reflective white conveyor belt. The sensor will “see” the product by the absence of reflected light from the belt.

Additional features include an optical design that reduces output false trigger due to background reflections, power, output and stability LED indicators, Micro QD connector design with 90°-swivel capability, protection from mis-wiring, dual NPN and PNP outputs, a fast response time of 1ms and a high degree of protection – to IP67.