The optical temperature measurement of bare metals at temperatures of < 200 °C is a difficult measurement task for infrared thermometers due to the low heat radiation. Standard low-temperature pyrometers do not provide reliable measured values, as the object radiation is strongly influenced by the ambient conditions.

So far, special alternating light pyrometers have been used for this measuring task. However, these devices require a motor-driven perforated disc in front of the lead sulphide sensor for signal evaluation. This limits the service life of the devices and allows operation up to a maximum ambient temperature of 50 °C. In addition, the measuring method is not suitable for fast moving objects.

KELLER Infrared Temperature Solutions (ITS) as one of the innovative leading companies in the field of optical temperature measurement has developed a new measuring method for the acquisition of smallest infrared signals on the basis of the modern, maintenance and wear-free continuous wave light technology. The core of the invention is a powerful lens in combination with a new photoelectric sensor and an extremely space-saving signal processing system. A high-performance processor calculates the mathematical algorithm for linearization and compensation of the ambient temperature and delivers a high-resolution output signal with minimum noise. Even under most extreme conditions, i.e. short measuring times, low object temperatures and low emissivity of the measuring object, the patented signal processing delivers stable measured values from 75 °C.

The new technology is now implemented in all device series. With measuring times in milliseconds, the devices are ideally suited for fast measurements on moving objects such as in coil coating systems or for short inductive heating processes.

KELLER who is expert in the field of optical temperature measurement – has developed new stationary and portable pyrometers for the various measuring tasks in combustion plants.
So-called flame pyrometers are used for non-contact measurement of the flame temperature. A complex algorithm in the devices ensures that fluctuations in particle density and particle size are compensated for over the length of the measuring section and do not interfere with the measured value.
In order to keep the pollutant content in the exhaust gas as low as possible, a defined minimum temperature of the hot gases must be reached quickly. Special gas pyrometers with a selective spectral sensitivity are necessary for temperature measurement. The devices detect the infrared radiation on the CO2 or CO band, depending on the fuel, the type and size of the combustion plants.
When measuring the firebed, pyrometers have been developed which cannot be influenced by the hot flue gas in the field of view to the firebed. The devices measure in a very selective wavelength range. In this range, water vapour (H2O) and carbon dioxide (CO2) are transparent and do not influence the measured value.
The devices are based on modern continuous wave light technology and therefore work without moving components. They are wear-free and have no time limit on their use.
The devices of the CellaTemp PK series are used as a direct alternative for thermocouples. Thanks to the compact design in the M30 housing and the high optical resolution with a narrow optical cone, the devices can be easily mounted on an existing kiln opening for thermocouples. The mounting accessories with bayonet connection and integrated sapphire protective glass can be opened quickly and without tools to check the measuring device, clean the protective glass and check if the kiln opening is clogged. An axial air nozzle with circulating air flow reduces the risk of contamination with minimum air consumption.
The stationary devices of the CellaTemp PA series have a sighting device for optical inspection, either as through-the-lens sighting device or video camera.
For all applications, the CellaPort PT series also offers portable pyrometers for quick and easy temperature control at the various measuring points.
KELLER ITS will be represented with a stand on Thermprocess (Hall 9/A32) and on Gifa (Hall 10/A25) and will be pleased to inform you about innovations.

Optical temperature measurement has meanwhile established itself in many applications. By using the Planck distribution curve an infrared thermometer or pyrometer calculates the temperature from the infrared or thermal radiation emitted by a measuring object. Within milliseconds, the radiation is measured without contact. The optical measuring method allows a temperature measurement from a safe distance, on moving objects or on sensitive surfaces such as paint layers or liquids. Even temperatures above 2,000 °C or inaccessible objects such as encapsulated kilns are typical applications for optical temperature measurement.
As a special feature of the optical temperature measurement, the emissivity of the object must be taken into account. The emissivity is a material property and a measure of the ability to radiate heat. The value is specified as the ratio of the radiation of an ideal “black body” with a range from 0 to 100 %.
The emissivity depends on the measuring object, the surface condition, the wavelength of the radiation and on the ambient conditions. In the literature, you only find approximate, theoretical values. For precise determination of emissivity, a comparative measurement with a contact thermometer is recommended. However, the contact measurement can also be faulty and a comparison measurement at the same time and place is often not possible to realise in practice. Then it is helpful if at least the error about the maximum possible measurement deviation can be estimated.
For this purpose, KELLER Infrared Temperature Solutions (ITS) – one of the leading manufacturers of optical temperature measurement devices – has developed an emissivity calculator. This calculator is available as online tool on www.keller.de/its. If the real object temperature is known, the emissivity to be set for the selected pyrometer can be determined by the calculator. A second calculation method determines the influence and the deviation of the measured temperature by varying the possible emissivity.

Modern information and communication technology offers innovative solutions for providing information and data regardless of the location far beyond the current practice. Digitalization thus opens interesting fields of action for companies, especially in terms of service.
KELLER ITS – one of the leading manufacturers of optical temperature measuring devices – follows this development and presents the new information and service app “KITS” on Thermprocess 2019 in Düsseldorf. The app implements the different possibilities of a modern digital service concept.
The Industrial Solution Guide in KITS helps prospective customers in selecting the most suitable device and accessories for their industry and application. All information available on a product, such as technical data, operating and commissioning instructions or dimensional drawings are directly available on site via the app on the smartphone or tablet. For this purpose, you simply scan the barcode or enter the type of instrument. For the electrical connection, the setup of the measuring system or in case of any malfunctions it is no longer necessary to search for the documents.
The field-of-view calculator is a useful tool for selecting the optical property of the instrument as well as for setting the appropriate focus distance of the pyrometer during commissioning. The emissivity calculator is an important tool for setting the parameter of the device to find the correct emissivity setting. In addition, you are able to determine the real measurement uncertainty under the given measurement conditions.
For quick help, our service hotline is directly available. The KITS App currently supports 8 languages and meets the requirements for a modern service management to get all necessary information quickly, easily, at any time and worldwide.

The implementation of integrated networking and communication from the machine level to the ERP software is a high challenge for automation technology in machine and plant construction as well as for the manufacturers of sensors and actuators in this extremely rapidly developing technology, in order to be able to follow the state of the art and the innovative machine concepts. In order to be able to manage the large amount of new process data of the "smart" sensors, a new interface technology with higher transmission rates had to be created.
In this context, the world’s leading manufacturers of control and fieldbus systems joined forces 2007 years ago to create a uniform, system and company independent new standard. The result was the invention of the IO-Link interface technology. Sensors and actuators with IO-Link communication interface can be operated in all common fieldbuses such as Profibus, Profinet, Modbus, EtherCAT or CAN-bus and thereby solve one of the still largest problems of bus specific device interfaces.
When specifying the IO-Link interface in accordance with IEC 61131-9, particular emphasis was placed on standardization, operational safety and simple hardware and software commissioning and cabling of the intelligent and complex sensors and actuators. Therefore, IO-Link is rightly called the industry's USB interface for controlling machinery and equipment. It was also important that the IO-Link devices could also be easily implemented in existing systems.
Several measured values, diagnostic information for demand-oriented maintenance, information on operating states or fault messages can be transmitted in parallel via IO-Link. Parameterization takes place flexibly during operation via the control system, depending on the production conditions.
The central parameterization of the devices from the highest level of process control contributes to operational safety. When changing a sensor, the identification is automatically checked and the configuration parameters stored in the IO-Link master are transferred to the sensor. The connection of a wrong device or a faulty configuration is therefore excluded.
In order to follow this technological progress, the business unit “Infrared Temperature Solutions” of KELLER HCW GmbH – one of the leading companies in the field of optical temperature measurement – will present a new product at Thermprocess 2019 in Düsseldorf as the first manufacturer worldwide to present focusable precision pyrometers equipped with the innovative IO-Link interface.
Altogether, the new CellaTemp PX series has 22 basic models with measuring ranges from 0 – 3,000 °C. In combination with the 5 focusable lenses, the more than 100 device versions can be used for various measuring distances and object sizes. You can choose between a through-the-lens sighting device, a laser pilot light or an HD video camera. The variety of variants covers the complete application ranges of optical temperature measurement from the iron and steel industry, the cement, glass or ceramic industry to combustion plants.
In order to be able to use the devices in existing process control systems with analogue signal transmission, the devices of the CellaTemp PX series have the classic 0(4) – 20 mA analogue output as well as two switching outputs in parallel.

.

Today’s demands on the mechanical, forming and machining properties of foundry products have increased significantly in recent years. This is due both to the complexity of the components and to the objective of saving material and weight. In addition, the market is being flooded by low-cost suppliers. Efficient production in the foundry sector in Europe is only possible by focusing and specializing on high-quality products.
This, however, requires that demands on quality are defined, checked and adhered to from the raw material through to the entire production process. Especially the prescribed temperature of the liquid metal when pouring into the mould must be ensured.
The optical temperature measuring method with pyrometers has meanwhile established itself in steel mills and foundries. For this purpose, KELLER Infrared Temperature Solutions - who is one of the innovative leading companies in the field of optical temperature measurement -has developed a unique measuring method with the CellaCast measuring system. By means of a CSD (Clean Surface Detection) function and a rectangular measuring field, the pyrometers are able to filter the correct temperature of the liquid steel and iron even with slag and oxide on top of the surface.
The measuring system is used to monitor continuously the temperature in the runner of blast furnaces or cupola furnaces. At automatic casting machines, the temperature of each production part is measured and recorded at the critical process point, i.e. when filling the mould. Faulty production parts can be sorted out directly or the casting process can be stopped immediately when reaching the minimum permissible limit temperature.
The CellaCast System can be integrated into the plant control or can be used as stand-alone solution to display the measured values with the number and analysis of the production parts on a PC and save them automatically in a database.
As an exhibition novelty at the Gifa 2019 in Düsseldorf, KELLER ITS will present the CellaCast PX measuring system with the modern IO-Link interface technology. When specifying the IO-Link interface in accordance with IEC 61131-9, particular emphasis was placed on standardization, operational safety and simple hardware and software commissioning and cabling. Therefore, IO-Link is rightly called the industry's USB interface for controlling machinery and equipment. Several measured values, diagnostic information for demand-oriented maintenance, information on operating states or fault messages can be transmitted in parallel via the digital interface. It is also possible to dynamically adapt the device parameters with the PLC to the material during operation via the interface.

KELLER Infrared Temperature Solutions (ITS) has been present in China for 20 years and represented on the market via the exclusive cooperation partner GeramanTech. It all started in 1999 when a Chinese steel factory contacted GermanTech just founded by Dr. Zhou to equip their production plants with further optical temperature measuring instruments by KELLER. Even though GermanTech was originally founded as a cooperation partner for German companies in the field of nanotechnology and the bad experiences KELLER ITS made with the previous partner, both partners decided to continue their cooperation after the successful completion of the first project and laid the foundation for a great success story.

Mr. He took over the job at GermanTech to sell KELLER’s precision measuring instruments for optical temperature measurement on the Chinese market. One of the major problems at the beginning was the language barrier for the description of the products. After translating all marketing material, the products were more and more accepted by the Chinese customers as an alternative to the foreign products already established on the market. In 1999, there were no serious Chinese manufacturers of pyrometers.

The participation in the first Metal+Metallurgy trade fair in Beijing in 2005, where the Deutsche Messe AG Hannover organised a joint stand for German companies, was a further step towards successful cooperation. Since this time GermanTech / KELLER has participated in 1 - 2 trade fairs per year in China to attract interested parties in this classical way. The Internet was still in its initial phase at that time. The great importance of this marketing medium was quickly recognized and a Chinese homepage was created and adapted to the KELLER standard.

In 2010, GermanTech was opened as official service centre of KELLER ITS in China beyond the pure sales activity. From this time on, measuring services and commissioning could be carried out by a local team of technicians.

In the meantime, the KELLER ITS brand has established itself as one of the leading international company and specialist for high-quality infrared temperature measuring instruments on the Chinese market thanks to the good work of GermanTech.

During the Metal+Metallurgy trade fair in Shanghai, which took place from March 13 – 16, 2019, the 20th anniversary of the cooperation was duly celebrated with the local sales team managed by Mr. He, with Liliang Sun who is responsible for the technical and commercial activities as well as with the founder Dr. Zhou.

For 20 years now, the local sales and service partner German Tech has been representing the Infrared Temperature Solution (ITS) division of KELLER HCW GmbH on the Chinese market.

For the 15th time KELLER participated with German Tech in the Metal+Metallurgy fair from March 13 – 16, 2019. So far, this fair took place once a year alternately in Shanghai and Beijing. However, according to the organizer of the exhibition, the fair will only be held in Shanghai in the future. With this, China wants to advance the further development of the city and surroundings of Shanghai as industrial metropolis for basic technologies.

Numerous Chinese and internationally well-known companies of the machine-building and plant engineering sector, producers of finished parts and manufacturers of consumables for the iron and steel industry presented their products at the fair. Despite the Internet, the interest of the visitors to inform themselves personally about the innovations of the companies is still high.

KELLER Infrared Temperature Solutions – specialist in the field of optical temperature measurement – once again proved its technological leadership at the trade fair. The CellaTemp PX was the first company in the world to present another pyrometer series with optical sighting device equipped with the innovative IO-Link interface technology. The internationally standardized IEC 61131-9 interface forms the basis for the implementation of Industry 4.0 for the acquisition and analysis of machine and plant data far beyond the previous level of measurement information. Thanks to the simple handling and the very high safety standard, the IO-Link is rightly referred to as the USB interface of automation technology.At KELLER’s exhibition stand several visitors, mainly from the field of foundry technology, were welcomed and the CellaCast measuring system especially developed by KELLER for the measurement of liquid metal was presented. With the measuring system the foundries are able to record and document the correct casting temperature for each cast production part. Compared to the usual measurement with measuring probes which are immersed in the melt, optical temperature measurement does not produce any permanent consumption costs, so that the CellaCast system is already amortized within a few weeks.

This month Keller ITS and AXL Imperial have signed a contract of exclusivity to distribute all the products and solutions for infrared pyrometers and non-contact thermometers.

M. Gouliaris has set AXL Imperial in 2017 to propose high quality industrial products for all industrial Greek actors. Amongst many types of sensors and other industrial equipment, the infrared pyrometers will complete this portfolio. Present in two sites in Greece and one in Cyprus, AXL Imperial can respond quickly to its clients.

We expect successful results especially with unique products like the CellaCombustion to measure the temperature of combustion gases, firebed or flame in wasting plant or cement plant. Special models like the CellaTemp PKL 29 will be appreciated by the aluminium industry which is very present in Greece.

Also the new universal IO-Link digital interface which equip Keller ITS products will bring an up-to-date solution for modern plants of the 21 st century.