What You Need To Know About Different EMC Tests

Electromagnetic compatibility (EMC) testing is a necessary process to ensure that electronic devices are safe and do not cause interference with other electronic components. EMC testing determines whether a product or system meets regulations and standards.

The two primary types of EMC tests include: immunity testing and emissions testing.

What is Immunity Testing?

Electromagnetic compatibility (EMC) immunity testing is a process to check whether an electronic product or device is resilient to electromagnetic interference (EMI) in its operating environment.

Testing for Radiated Immunity

Radiated immunity tests are performed inside anechoic shielded chambers. The chambers, constructed of highly absorbent materials mounted on metal surfaces, block out any external interference while enabling the production of radiated electromagnetic fields inside the chamber.

By doing so, anything subject to electromagnetic radiation can be monitored while ensuring accuracy in measurement and precise results. 

The chamber can be used to protect any testing equipment from unwanted radiation that may affect the outcome of the test. 

Testing for Conducted Immunity

Conducted immunity testing is a process used to evaluate the performance of electronic devices in an environment where they may be exposed to electrical noise.

The test involves exposing products to conducted RF voltage simulating a source such as a power supply, which produces low-frequency, pulsed signals that can interfere with electronic components inside the device. 

The purpose of the test is to measure how well the device responds and whether it is able to operate correctly in a noisy environment. 

Key Distinctions Between Radiated Immunity and Conducted Immunity

In conducted immunity testing, a product is exposed to radio frequency voltage on signal and power lines, while in radiated immunity testing it is exposed to higher-frequency radiation. 

While conducted immunity tests are often used for lower-frequency (150 kHz – 80 MHz), such as those emitted from power supplies or electrical equipment, radiated immunity tests are used for higher-frequency signals (80 MHz – 6000 MHz) such as those from mobile phones or radio stations. 

What Is Emissions Testing?

Electromagnetic compatibility (EMC) emissions testing is a process to check the amount of radiated and conducted noise a product generates. 

It measures how much electromagnetic energy is emitted by the product, and the potential for interference with other electronic components or wireless networks.

Testing for Radiated Emissions

Radiated emissions can cause potential issues regarding electromagnetic interference (EMI) regulation requirements set by both local and international agencies such as the FCC and CE Mark.

Radiated emissions testing is conducted on the Open Area Test Site (OATS) to measure the amount of electromagnetic energy emitted from a product. Open Area Test Sites (OATS) are specialized facilities designed to assess Electromagnetic Compliance (EMC) in electronic equipment. 

Testing for Conducted Emissions

Conducted emissions are electrical signals generated by a device as it operates, which can interfere with other electronic devices that are nearby or connected to it. 

The most common types of conducted emissions come from power supplies, motors and relays.

The purpose of testing for conducted emissions is to measure how much interference is potentially generated by a device and whether it meets the standards set out in the EMC regulations. 

This type of test is especially important for products that will be used near sensitive electronic components, such as medical equipment or communications systems.

GME Is Here To Help

Green Mountain Electromagnetics is an ISO 17025-accredited laboratory that tests for product compliance with CE, FCC and Military standards.

With 30 years in the industry, our team of experts is equipped with the latest technology and knowledge to ensure reliable test results. GME is A2LA accredited and supports clients, developing long-term business relations.

Contact us today to find out more about our services!