What is Electromagnetic Compatibility (EMC) Testing?

2 Answers
Can you answer this question?

Rich Markley - Rohde & Schwarz

Apr 3, 2019

In a nutshell, electromagnetic compatibility (EMC) testing is testing we perform to ensure that the electronic devices that have come to play such a big role in our lives 1) have sufficient immunity to electromagnetic interference and 2) they do not create excessive electromagnetic radiation.

These are both very important issues. Insufficient immunity can lead to malfunctioning of electrical and electronic devices. Worst case, national security or public transport can be affected or disrupted when electronic systems fail to function properly in adverse electromagnetic environments. Excessive electromagnetic radiation by a device can create other devices to malfunction, and in some cases, human health hazards.

In view of such implications to public health and safety, most countries have established regulations to ensure the electromagnetic compatibility (EMC) of all electrical and electronic products. Failing to comply with these regulations can have consequences for the exporter or manufacturers in terms of product liability or denial of entry into markets.

Editorial Team - everything RF

Nov 13, 2017

All electronic devices emit some level of electromagnetic waves while operating, if these emissions are excessive then they can impact other devices that are operating around it by causing interference. EMC (Electromagnetic Compatibility) is a compliance test that checks the ability of a device to work as intended without affecting the working of other devices in a common or shared Electromagnetic Environment. This test makes the electromagnetic environment safer and ensures that multiple devices can work together without impacting each other.

EMC test checks any electronic device on two aspects:

  1. Emissions Testing - The test ensures that the operation of the device is not generating electromagnetic energy to such high levels that adversely affects the electromagnetic environment, causing improper functioning of other devices or damaging them.
  2. Susceptibility & Immunity Testing - This test checks the equipment's immunity to the unwanted signals. There is always some level of interference or unwanted signals in a shared environment. So any device complaint to EMC should have the circuitry that is immune to certain level of interference and perform as expected in a common electromagnetic environment.
The Federal Communications Commission (FCC) sets the standard for Electromagnetic Compatibility in the United States. FCC Part 15 rules define limits for the amount of unlicensed radio frequency interference that can be produced by consumer electronics and other devices.

MIL-STD 461 and MIL-STD 464, which outline EMC and environmental requirements for components/subsystems and systems for military applications.

Outside of the U.S., various ISO, IEC, CISPR and other standards define acceptable limits of EMI and overall EMC. In some industries and markets, compliance with these standards is voluntary. In others, it is a requirement.