What Is EMI and RFI Shielding and Why Is It Important?

Electromagnetic radiation generated by power stations, electrical devices, and natural sources such as lightning and solar flares can cause electromagnetic interference (EMI). When EMI is caused by energy in the radio frequency (RF) spectrum, it’s referred to as RF interference (RFI).

EMI can disrupt the performance of electrical circuits, wireless networks, and sensitive electronic devices. Additionally, cybercriminals can intercept electromagnetic radiation and RF signals and reconstruct sensitive data.

However, EMI and RFI can be blocked by certain materials, including copper, aluminum, and steel. These materials can be used to shield electronic equipment from EMI and RFI to prevent cross-device interference and unauthorized interception of electronic communications. Properly shielded data center cabinets can effectively block EMI and RF signals.

History of Electromagnetic Interference Challenges

Engineers have been grappling with EMI since the advent of radio communications in the early 20th century. By the 1930s, standards were developed around electromagnetic compatibility (EMC), which seeks to control the unintentional emission and propagation of electromagnetic energy by electronic equipment through grounding, shielding, or filtering.

In the 1970s, the U.S. Federal Communications Commission established legal limits on electromagnetic emissions. The European Union followed suit with its own requirements in the mid-1980s. These regulations continue to evolve as the world has become increasingly crowded with electronic equipment.

How to Prevent & Block EMI

Despite regulation, there’s sometimes little to be done to prevent EMI-related issues. Most IT equipment can withstand reasonable levels of EMI, but a data center located near a power station or commuter train line may experience problems. In that situation, the only remedy is to shield the equipment.

Highly sensitive applications and data, such as those related to national security and critical infrastructure, require shielding to prevent eavesdropping. These use cases require a purpose-built cabinet capable of attenuating signals from 1MHz to 40GHz.

Real device testing is another use case for RFI and EMI shielding. Mobile app developers often need the ability to test various devices and must isolate them so that their wireless signals don’t interfere with one another.

Best Protection Against EMI

The DefenseShield™ RF Shielded Cabinet from Enconnex provides the best protection against EMI. It’s a standard 42U (customizable) cabinet constructed from aerospace-grade shielded aluminum to effectively block interference. All the seams and penetrations of the cabinet are shielded using copper-nickel gaskets for maximum protection. The DefenseShield cabinet provides 85db of attenuation at frequencies ranging from 1MHz to 10GHz. Light cleaning of filters is all that’s required to maintain the DefenseShield cabinet. We suggest that customers inspect gaskets monthly or as needed.

Customizable I/O panels provide flexible connectivity options. A special power conditioning unit mounted to the top or bottom of the enclosure protects against the propagation of frequencies above 150kHz with minimal current leakage. Single-phase or three-phase power options from 15A to 30A (32A international) are available with one or two input feeds.

Data center cabinets need airflow; otherwise, the IT equipment will overheat. The DefenseShield cabinet has ten hot-swappable fans providing 235 CFM of airflow each that rapidly exhaust heat out of the enclosure. Power is automatically routed to a second circuit if the primary circuit fails to ensure reliable operation of the fans.

RF Shielded Enclosure Use Cases

The DefenseShield cabinet can help protect equipment from EMI and side-channel attacks that use power analysis. It’s also ideal for environments where sensitive data must be isolated to meet strict security and regulatory requirements.

Additionally, we offer RF shielded cabinets for testing mobile devices and applications requiring wireless attenuation. Similar in form to DefenseShield, our DevShield cabinet can support up to 400 devices in a single rack that incorporates compute, storage, networking, and power resources. Sliding shelves include trays that hold mobile devices in place and pull out completely for easy access to all devices.

EMI doesn’t have to affect data center equipment or create cybersecurity threats. Let Enconnex show you how our DefenseShield RF Shielded Cabinet can protect against EMI while delivering all the features you need in a high-quality enclosure.