Preventing electromagnetic interference

Thanks to digitization and automation, factories are becoming smarter and smarter. This also means that large amounts of electrical energy and data are often transferred in a limited space. This increases the risk of electromagnetic interference. Even one poorly shielded connector can cause the entire production to grind to a halt. The solution to this? Electromagnetically compatible (EMC) components.

"Electromagnetic compatibility means that components and systems - often electrical and electronic - must continue to function properly in an electromagnetic environment without themselves causing electromagnetic disturbances that are intolerable to other components or systems in that environment," explains Alexandru Custura, Product Manager at LAPP from. "So a device must not cause interference and must not itself be electromagnetically disturbed by its environment."

The operation of EMC

Due to the growing issue of electromagnetic interference, EMC solutions are growing by seven percent annually worldwide. "When electromagnetic interference or disturbance occurs, it can always be traced to an interference or disturbance source. For example, consider a high-current device such as a frequency-controlled motor or a cable. The interference source corresponds to an interfering device, the interference receiver, such as a sensor or data network cable. The coupling mechanism causes the interference."

Link types

"There are four coupling types," Custura continues. A first is galvanic or conductive coupling. In this, the interference source and receiver are connected to each other, for example via a common grounding conductor. An interference current through the common grounding conductor causes the interference. A second type is radiative coupling. This usually occurs when the interference source and receiver are far apart. The conductors act as antennas, so to speak, leading to electromagnetic interference."

Capacitive coupling is a third type. "Here there is little space between the interference source and receiver but they are not physically connected to each other. The interference is caused by the electric field present. Finally, there is the inductive coupling type. Again, there is little space between the interference source and receiver while they are also not connected to each other. The interference is caused by the magnetic field present."

In practice, there are often multiple links in one situation. Then it is important to suppress them, for example by using shielded cables.

A good EMC

"To ensure good EMC, you have to start with good grounding," Custura states. "This is crucial for EMC. After all, without good grounding, shielding has no effect. Data cables should therefore always be grounded at both ends. During installation, it is important that the shielding always completely covers the cable surface and is placed all around in a connector housing at both ends of the cable. To fully relieve customers, we offer LAPP the Ölflex Connect program. This includes ready-made assembled cable systems, with or without cable caterpillar, which are fully tested and delivered to the desired length."

LAPP has even more power and control cables in its range, think cables with tin copper plating, copper wire wrapping or aluminum laminated plastic foil. "There is a solution for every application," he said.

Connectors

In addition to cables, EMC connectors are important. "Our EMC connectors offer 360-degree shielding and vibration-resistant connection. Combined with our Skintop Brush cable glands, they provide easy installation and maximum EMC." Often, EMC cable glands are already included in the LAPP-connector systems integrated. "They make it possible to connect a protective hose and put the cable shield in contact with the working or PE contact of the connector system." Finally, Custura mentions the zeroCM technology of LAPP. This is a patented cable design that provides 100% electrical symmetry. It significantly improves EMC."

A good understanding

Companies are integrating more and more electrical and electronic components, increasing the risk of interference. "A good understanding of the system and the selection of the right components are necessary to suppress electromagnetic interference. We offer integrated solutions in the field of cable and connection technology and have extensive knowledge and expertise to provide companies with the solutions that prevent interference."