Noncontact temperature monitoring in hazardous areas.

All models of the versatile Raytek® MI3 Compact Series infrared sensors are now also available as intrinsically safe versions for use in hazardous environments. Intrinsically safe devices prevent explosions in hazardous locations by limiting the energy and surface temperature of the device under normal operation, or when conditions arise that could become hazardous. Devices are approved as intrinsically safe only after passing the rigorous approval process required by a recognized entity.

The intelligent MI3 miniature sensors are now fully ATEX and IECEx certified for use in Zones 1 and 2 (gas) and Zones 21 and 22 (dust). Raytek supplies a complete intrinsically safe package, including the sensor, communication box and an Ex power supply. All three components are IP65 rated. One or two intrinsically safe MI3 sensing heads can be powered by one power supply. The sensor cables can be up to 30m (98ft) long in total, providing high flexibility for setting up safe monitoring scenarios. The communication box, power supply, and sensing heads can each be easily exchanged in the field without re-calibration of the entire system.

The MI3 is a rugged, IP65 stainless steel miniature pyrometer with integrated electronics. It is the smallest, fully functional, standalone digital infrared temperature sensor for fixed installations on the market today.

The MI3 series comprises pyrometers for various spectral ranges and applications, including the 1M and 2M shortwave models with an excellent 100:1 resolution and 10 ms response time, which are suitable for monitoring temperatures up to 1,800°C (3272°F). Each intrinsically safe MI3 sensing head is labeled with the Ex certification. The MI3100 model’s Ex certification also covers the laser sighting function for easy positioning and aiming. MI3 sensors have excellent EMC characteristics and can be used in ambient temperatures up to +180°C (356°F). Communication boxes are available with RS485, Modbus, Profibus, Ethernet TCP/IP and Profinet IO interfaces, and with four galvanically isolated analog outputs. Automatic head detection and digital communication between sensor and box enable plug and play.

With the addition of ATEX and ICEEx certification, the MI3 series can now be used in many additional areas - for example, in steel industry processes using hydrogen atmosphere, such as galvanizing, annealing, plating and coating. Other application areas include hydrogen reduction in the solar industry, petrochemical (sulfur recovery, boilers, reactors, pipes, flare control) and chemical (fertilizer, starch, alcohols, flower, vinyl) processes, mining (monitoring) conveyors and equipment, fire detection and storage terminals (coal, wood pellets, sulfur, petroleum coke, starch), hazardous waste disposal and sewage, as well as ink, laminate and coating processes that emit volatile vapors, and many more.