The fundamental uses of photoelectric sensors are measuring distance and detecting an addition or removal of objects. However, there's also the photoelectric light sensor and photoelectric switch sensor, used in automatic switches; as well as the photoelectric speed sensor, which can play a role in determining the rotational speed of a motor. In this guide we are concerned with the basic position-monitoring capabilities of this type of sensor.

Many photoelectric sensors are versatile, and have several modes. For instance, many can handle both presence detecting or position detecting. When you buy, also make sure to get a unit that has a suitable detection range and response time for your applications. Here are the main types of position photoelectric sensors:

1. Photoelectric beam sensors consist of an emitter which sends a beam to a detector. The device detects an object when it interrupts the path of the beam.

2. Retroreflective photoelectric sensors have an emitter and a detector right next to each other. The emitter sends a beam to a reflective surface, which sends it back to the detector.

3. Photoelectric proximity sensors pick up reflections off of a target object. These have multiple modes and innumerable uses.

Action Steps
The best contacts and resources to help you get it done

Buy heavy-duty industrial photoelectric sensors

Anything manufactured for the industrial sector has got to be rugged. Also, proximity photoelectric sensors probably serve the most purposes.

I recommend: Rockwell Automation carries a number of photoelectric sensor types, including both retroreflective and proximity sensors, many of which have multiple modes and high versatility. Additionally, they design their equipment with thick cases that hold up to industrial wear. Panasonic carries many different compact photoelectric sensors, including some that are water resistant. For whatever else you need, Pepperl+Fuchs should take care of it. They have a number of photoelectric sensors, accessories and products.

Locate transmitted or through-beam photoelectric sensors

Transmitted beam photoelectric sensors probably have the most commercial and domestic uses. If this is the type you're looking for, search websites with good products and a wide selection.

I recommend: Home Security Store carries an easy-to-use security photoelectric sensor that functions as a photoelectric motion sensor. It includes a LED that indicates proper alignment for installation purposes, and its two components have a range of 100 feet. Alternatively, MSC Industrial Supply Co. carries through-beam photoelectric sensors for almost any use.

Check out retroreflective photoelectric sensors, including those made for garage doors

If your applications call for retroreflective sensors, then some sources provide larger selections than others.

I recommend: Click Automation carries some of each type of photoelectric sensor, including several series of retroreflective models with sensing ranges up to 10 meters. If you're looking for photoelectric safety sensors for your garage or large gate doors, Quantek Systems Limited carries a retroreflective photoelectric sensor that will do the job.

Tips & Tactics

Helpful advice for making the most of this Guide

• •  Some photoelectric sensors can even determine the color of a target object.