Expensive downtime in complex industrial plant is often attributable to malfunctioning of the closed- and open-loop control technology. These malfunctions are, in turn, often caused by unwanted interaction between the electricity supply and the control system. The effect is that communication between components is impaired. It is not always possible to apply the classic error analysis methods in the search for the causes of such interference.

For these reasons, IMMS has developed a compact, smart current clamp for Indu-Sol to manufacture. It is a mobile device, energy autonomous, which will register automatically and continuously the true RMS level of parasitic current in a wire of the communication bus system in industrial plant for a period of 14 days, recording this on an SD card for later detailed analysis. The energy for its operation is stored in six LR6 mignon batteries supplying a total of approximately 20 Wh. The clamp recognises the parasitic currents from threshold values and is able to register values across a wide range, between 10 mA and 30A, at up to 40 kSa/s, digitising them at 16-bit resolution. It will display the root mean square value (RMS) of the current parasitics in either numerical, graphic or spectral form and can be easily and intuitively operated. If the owners of industrial plant use several clamps at once they can establish the site of the parasitics, thus greatly reducing the effort required for analysis.

The Institute took many serial measurements for energy consumption by a variety of microcontrollers and for the time they took to go through certain algorithms. To set optimum dimensions for the batteries with the necessary capacity, IMMS identified the current consumed by the system in each operational cycle. The peak values were also identified for the supply current during the measurement procedures and the order in which the process was carried out was optimised in the software to avoid too much stress on the batteries during operation. The software to carry out the initial evaluation of the data in the current clamp was likewise made at IMMS and then implemented.

The IMMS has supported the development of the current clamp up to production transfer. It is marketed by Indu-Sol under the name EMCheck® ISMZ I.