interference resistance
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Interférence résistance: Aim, causes and solutions Why are interference-free products so important? What is meant exactly by interference-free”? Technology is generally very susceptible to in-terference. Measurement, automation and control technology is already exposed to potential interference in the harsh industrial environment. There are many reasons for this: EMC radiation, the insertion of motor contactors along with elements such as the motors and valves them-selves provide a tough test of the interference resistance of the technology. Every element of the measurement chain can be affected by interference: From the sensors that perform the measurement through the lines to the control unit. Even the signal output can be influenced by radiation, for example. This is precisely where interference-free products from ADDI-DATA come in. They help to protect applications and hardware from external unwanted and possibly dangerous interference. Interference-free products not only protect products and their applications, they also simultaneously guarantee the protection of their environment. A simple example: mobile phone radiation. The electromag-netic field of a mobile phone can limit the functions of aeroplanes or interfere with measuring devices in hospitals. This could have serious consequences and must therefore be avoided. Interference-free products from ADDI-DATA specifically en-sure that damaging external influences are protected against AND interferences from the environment are avoided. Protection where needed The use of interference-free products ensures that processes run reliably as the hardware is better protected from possible damage through the use of interference-free products. If, for example, there is an overvoltage while using an ADDI-DATA communication board with optical isolation (for each port), only one port will be affected. When using a non interference-free product without opti-cal isolation, the whole computer can be destroyed if there is an overvoltage. Interference-free products thereby prevent the complete failure of a device and the possible consequences that this would entail for the measurement chain. In addition, interference-free products from ADDI-DATA guarantee correct measurement values, which in turn significantly increase productivity. Peaks or noise created by interference are not recorded when receiv-ing the signal. Therefore stable signals can be guaranteed. At the same time, interference-free products prevent interference with and possible damage to other devices in the immediate surroundings, as the technology used does not itself cause any interference to its surroundings. The causes of interference To create steel sheets, iron ore is melted in a furnace and cast as steel blocks or slabs. These slabs are rolled out into a sheet whilst still warm in several rolling steps. In order to ensure that the com-pleted sheets are the same thickness throughout, the thickness of the sheet must be constantly measured during processing and the pressure of the rollers as well as the feed rate of the sheets must be adjusted accordingly. Separating the measuring point from the location of the corrective rollers or the control unit of the corresponding motors means relatively long distances to the relevant sensors. The MSX-Box with the ADDI-DATA boards APCI-3120 and APCI-1710 is integrated in a switch cabinet and thereby directly connected with the protective earth. However, as in the case of a steel-works, where extremely high loads are switched due to the inconceivably large masses to be moved and high currents flow, the potential for the ground connection of individual sensors or ac-tuators can change at short notice. These potential differences, which meet at a common point - in this case the MSX-Box - are known as ground loops. Ground loops can have different effects: from interference with the measuring signal in the form of peaks or noise, to destruction of the hardware itself, e.g. through overvoltage. However, this example only illustrates one possible consequence which entails the use of non interference-free products. The info@addi-data.com www.addi-data.com

The measurement and control chain is exposed to numerous interfering influences. Measuring errors or even failures may result from the lack of effective protection. cables of the device itself can also cause later interference. The topic of interfer-ence resistance begins with measurement and automation technology before the actual signal acquisition. Interference such as EMC radiation, switching contac-tors etc can have an effect directly on the cables between the signal source - the sensor - and the downstream connection equipment, e.g. clamping plates. Often, the interference originates...

Interference resistance: Aim, causes and solutions In order to keep the interference influences on the signals to a minimum, ADDI-DATA uses for its connection technology and the connected cables transorb diodes along with shielded and dual strand cables which are adapted specifically for the pin assignment of boards. Interference-free PC boards Interference-free PC boards from ADDIDATA contain filters for inputs and outputs and guarantee protection against shortcircuits, overtemperature and overvoltage. With analog signals, a differential signal transfer is generally recommended. As opposed...