Infrared temperature measurement rises to process challenges

Paul Boughton
Ircon, a worldwide leader in infrared (IR) non-contact temperature measurement, has introduced the new Modline 6 Series of infrared thermometers. This new line of high performance sensors features advanced signal processing and background-reflected energy compensation capabilities, and includes one-and two-colour fibre optic IR devices designed for harsh operating environments.

According to the company, the rugged Modline 6 Series thermometers deliver the best value in terms of price, performance, features and ease-of-use of any available fiber-optic infrared thermometer. They are used in a variety of demanding industrial applications, including metal heat treating, steel production, foundries, and primary and secondary glass (Fig. 1).

The Modline 6 firmware now provides engineers with enhanced signal processing options, including averaging, peak hold and valley hold. The thermometers also incorporate a state-of-the-art electro-optic design offering built-in compensation for background-reflected energy. These features are accessed via Modline 6 Multidrop support software, which is intended for remote sensor configuration and data acquisition, display and archiving. The software includes demonstration tutorials that pictorially guide users step-by-step through the setup of signal processing and programmable relay functions.

Proprietary electronics support other advanced features, including two-way serial communications, remote sensor setup and configuration, real-time display of target temperature, and field calibration software.

The sensor includes a fibre-optic re-imaging lens interfacing to an electronics box, which has a bright LED display for access to key sensor functions and live temperature output. So there is no need to open the electronics box when adjustments to sensor settings are required.

In addition, the new series of thermometers uses high-speed digital signal processors with an RS-485 serial data communications networking capability supporting up to 32 sensors.

Micro-Epsilon has expanded its range of non-contact IR temperature sensors to include a compact IR ratio temperature sensor (ratio pyrometer).

The thermometer CT ratio pyrometer is suitable for measuring the temperature of metals, metal oxides, ceramic or semiconductor materials in harsh, high-temperature environments, including metal casting, welding, forming and sintering.

It measures temperatures from 700-1800°C. The sensor functions according to the ratio principle and is insensitive to contaminants such as dust, smoke or steam that may partially obstruct the target.

Even in cases where the IR radiation beam is weakened to 95 per cent of its original intensity due to smoke or steam, the ratio pyrometer still provides faultless measurements.

The pyrometer operates on the two-channel measurement principle: two integrated IR detection channels with relatively close spacing, but with mutually different measuring wavelengths, produce two independent electrical signals.

These signals depend on the IR radiation emitted from the target and signal components, which are influenced by the optical transmission path between the object and the pyrometer or from changes to the object.

By taking the ratio of the two signals, the ratio-pyrometer principle eliminates (or averages out) any signal parts that are similar in both channels. The measured temperature of the object therefore only depends on the signal ratio and the emissivity ratio, or 'slope value'.

The ratio thermometer principle provides accurate results when measuring the temperature of objects with unknown or changing emissivity, assuming that the emissivity ratio is not changing over time or temperature.

The compact sensor head of the ratio pyrometer has a diameter of 25 mm and a length of 70mm, enabling it to be mounted into tight, restricted spaces in production lines and machines.

Typical applications include the temperature control of inductive heating coils, temperature measurement of the pouring stream on casting machines during the reheating of steel ingots and steel billets in forging processes, in general soldering and welding processes and in process steps in semiconductor production and in photovoltaics.

Micro-Epsilon offers an optional integrated Profibus DP interface or other plug-in digital interfaces including USB, RS232, RS485 or Ethernet and software that provides graphical interface and display, the logging of temperature readings of all output channels and signal characteristics over time.

Calibration Dynamics has introduced the CTR1000 handheld IR thermometer for the safe, non-contact temperature measurement of hot, difficult-to-reach or mobile objects between 60°C and 1000°C.

Equipped with an accuracy of two per cent rdg and a measuring distance of up to eight metres, the CTR1000 is suitable for applications where thermocouples or resistance thermometers cannot be used.

The current measured value is displayed on demand and has a resolution of 0.1°C. The two-point laser marks the diameter of the measuring area, preventing the measurement of unwanted areas away from the object under surveillance.

Variohm EuroSensor has launched its new ETIS line of non-contact IR temperature sensors with 150°C, 200°C and 800°C temperature ranges.

Designed for demanding tyre, brake and exhaust temperature measurement in autosports but suitable for a wide range of applications throughout industry, the ETIS series has a 1000 G shock rating and is packaged in a lightweight and durable aluminium housing measuring just 20 x 18 x 12 mm and weighing just 26 grams

Recent Issues