We want to help you understand what to look for in an infrared sensor so that you get the most out of it. Infrared sensors are used in proximity and position sensors. Infrared is an ideal choice for high temperature environments. Trigger points of up to or over 800⁰C are common in some applications. Infrared sensing technology is ideally suited for continuous casting processes, hot media mold filling and level sensing, high and low limit level controls, and measure/cutoff of hot cast or rolled materials. You should choose your specific sensor based on several important criteria such as sensing range, environment, location, and type of output.
The sensing range is a critical element in the selection process, and is generally dictated by the size, shape, speed, proximity, and of course the temperature of the item, media, or process to be detected. The range is determined by the viewing angle of the sensing gap as well as the actual sensing distance. Additionally, the proximity of the sensing head to the detected material must be considered, for protection from exposure to higher than compatible ambient temperatures.
Infrared sensors are available as self-contained assemblies that holds the sensing lens/aperture, the control module, and special high temperature wiring. Self-contained infrared sensors are available with special jackets or enclosures that allow connection of compressed air or cooling water to ensure long life in severe environments.
A remote sensing lens assembly and control module that is installed in a safe location should be used in application with excessive heat. Infrared sensors for applications such as this are available as a dual component system, made up of an infrared sensing head and a separate control module that relates to a fiber optic cable. This arrangement keeps the very rugged infrared sensing head close to the working environment for maximum sensing ability and the control module a safe distance away.
The type of output provided by the infrared sensor must also be considered. They are generally used as an input to a larger process control system. Infrared sensors are available to operate at various AC and DC voltage ranges, and provide corresponding voltage or current outputs.
The unique capabilities of infrared sensors make them an essential component of complex processes often found in steel mills, bottling plants, glass industries, die casting, spin casting, and other industries that use high temperature processes from raw materials to finished goods.