The following ten points of attention are important when efficiently developing applications with a high degree of electromagnetic compatibility (EMC for short).
1. Know what rules apply
Anyone who brings an electrical product onto the European market is obliged to label it with the CE mark. EMC is one of the conditions within the CE standard for electronic products. For many applications, such as medical equipment, specific requirements apply. It is therefore essential to determine in advance which statutory EMC requirements the product must meet.
2. Take EMC into account very early
The first step towards electromagnetic compatibility is awareness. By taking electromagnetic emission and immunity into account as early as the concept and design stage, drastic changes to the design afterwards are avoided. Before the actual engineering begins, an inventory can already be made of possible components or processes that are sensitive to interference. Only discovering insufficient EMC in the final phase often means a costly and time-consuming trip back to the drawing board.
3. Map out the environment.
When designing an application that is sufficiently protected against electromagnetic radiation, it is important to know the environment in which the application will be used. What radiation influences the space and how can enough immunity be guaranteed in the design? The electronics within the application itself are also a factor, as they too can be a source of emission. By having a good idea in advance of the expected circumstances, the design can be made in such a way that it offers the necessary protection against electromagnetic radiation.
4. Prevention is better.
It is becoming increasingly possible to modify control panels to achieve the desired level of EMC. Nevertheless, it is sometimes easier to limit the emission from the environment and to improve immunity in advance. Interference sources in the vicinity can be provided with a filter or placed behind a wall (shielding).
5. Choose the right hardware
By choosing materials and components with a high immunity in the design, electromagnetic interference can be largely reduced. Insulated cables and suppression components can play a major role in achieving the desired EMC level.
6. Ensure the correct software.
Interference due to radiation can also be counteracted with software. By measuring in which frequency area the disturbing emission enters, software can, for example, ensure that the working frequency of the touch screen is automatically shifted to another frequency. This is called frequency hopping. There are then several working frequencies available that are preset. The software automatically switches to a working frequency in an area where there is no interference.
7. Do pre-compliance tests
By testing in the development stage whether the desired EMC degree is achieved, more clarity and certainty is created about the performance of the final application. If adjustments need to be implemented, it is more efficient to do this as early as possible in the development process.As an EMC specialist, SCHURTER is able to simulate and assess EMC conditions in-house. Within a test setup, interference is introduced and special software measures and monitors how the application reacts to the interference. Based on the findings, the application can be specifically adapted to limit electromagnetic influences.
8. Choose the right technology
The smartphone has made PCAP touchscreens very popular. In industry, the medical world and the agricultural sector, too, this form of control is increasingly being chosen. However, alternatives such as membrane switches, push buttons or resistive touchscreens sometimes remain good choices, because they are less sensitive to electromagnetic radiation or, in some cases, can be completely shielded. For example, membrane switches can be provided with a foil that leaves normal operation of the switch intact but stops interference from radiation.
9. Provide the right housing
In addition to adjustments of the internal circuits of a control panel, the housing can also be designed and integrated in different ways. A dense metal housing can act as a Faraday cage that protects against external radiation. Openings in the housing, for example for connecting cables, can be sealed with specific adaptations to make them as radiation-resistant as possible and to maximise immunity.
10. Co-engineering with EMC-specialist
When developing applications involving EMC, it is very important that all parties involved work together. As a custom-made control panel manufacturer, SCHURTER is a specialist in the field of EMC and has specific expertise in the design, productionand integration of control panels in many sectors.
