YUMMY....DELICIOUS. WIRELESS TEMPERATURE SENSORS CONQUER THE WORLD OF CHOCOLATE PRODUCTION

Wireless data transmission technology has become an integral part of industrial automation. Wireless data transmission and its benefits are used for various purposes in food industry — even for chocolate production.

 

In some cases, the consumers have the questions about the availability and reliability of the measurement data, or of the components used, for example, whether big machines that work with the electromagnetic interferences are a reason for radio signal interruption. As their frequencies are usually higher than 1 GHz, they cannot have negative impact on the operation of Jumo Wtrans wireless temperature sensors, as they operate in the range 868–915 MHz. All clients, which have already tested Wtrans temperature measurement system, first of all, point out high reliability and different options for recording of the measurement data, convenient control and many available options for adaptation to the operational conditions.

Simplified control of the production process

Use of the wireless technology eliminates the need in the expensive setting of the wireline temperature sensors. The costs for setting up the wireless connection are much less than the costs for cable laying. Thus, a considerable amount of costs can be saved, in cases with the rotating containers. Chocolate production is an excellent example: during the production process, tanks with chocolate can be distanced to hundreds meters from the remote control. There is no need in slip rings any more, which have been used before to transmit a unified signal from the rotating machines. For control of the production processes, the wireless data transmission, with the wireless sensors, operating on batteries, can be used also with the wireline temperature sensors.

Within 2010-2013, sales of wireless components for process automation have grown averagely by 40%.

Temperature radio sensor and multifunctional radio receiver

In order to improve the quality and flexibility of the measurement data transmission and to increase the distance, over which they can be transmitted, Jumo has developed wireless temperature sensor T01.G1/G2 for mobile and/or fixed temperature measurement on the portable or stationary devices, and multifunctional radio receivers T01.EC1 with four analog outputs and T01.EC3 with two analog outputs and two relay outputs. All electronics is located in the handle of the probe and is protected by a waterproof housing of IP67 protection. The 50-ohm quarter-wave antenna, being a part of the product, can be connected directly or set as external. The maximum temperature range covered by antenna is -200 ... +600 °C. The accepted results of the measurements are converted and displayed. The measured values are available in the form of current or voltage proportional signals (0(4)–20 mA, 0-10 V), and via RS485 interface. All receiver outputs are galvanic isolated. Connection to the sub-systems of the higher level is performed through the digital interface with Modbus protocol. Such systems can be built, for example, using JUMO SVS3000 software for data visualizing or paperless recorders JUMO LOGOSCREEN nt, compatible with Modbus protocol and working in the master mode.

Sensitivity to changes in temperature under control

Wtrans temperature sensors are designed for temperature measurement in many stages of processing of the chocolate raw material and its further processing. For example, it is necessary to precisely control the temperature in the process of production of fillings for chocolates. It is not allowed to exceed the maximum allowable temperature, otherwise the taste of batches will differ. This can be avoided by using Jumo temperature sensors. Accounting and transmission of the temperature data by radio frequency gives the manufacturers of chocolate an opportunity of unlimited use of these data at different stages of production with different given values of temperature and on various rotating or mobile tanks.

Flexible temperature measurement is inevitable

One of the final stages of production includes mixing the ingredients, such as cocoa butter, cocoa powder, sugar, milk powder in melangeur, a type of huge mixer. The mass obtained in the process of mixing is almost dry, but at the same time it contains a lot of water, and dissolved sugar can partially crystallize. Consequently, the cracks are formed on the surface, where the cocoa butter is leaking. Without further processing, the chocolate mass becomes brittle and powdery. To prevent sugar crystallization, it is necessary to extract all moisture. To do this, the mass shall be put into a long granite vat, along which the granite rolls move back and forth. During this process the temperature rises to 76 ... 78 °C and the mass becomes liquid. The rollers hit the wall of the vat, and the chocolate mass falls from the rollers back into the vat. In this case, the residual moisture evaporates and consists less than 1%. At this stage of production, the wireless temperature sensors ensure accurate temperature control. The chocolate industry, as many other sectors of the food industry, has several processing stages, which the food products undergo at different temperatures. First, they are dried, and then heated intensively to be cooled down again. The finished product is packed and sent to the warehouse.

The benefits of using wireless temperature sensors are evident: no long wires and cables, saving on installation and maintenance, efficient operation in difficult operating conditions.

Prepared based on JUMO materials.