What is the Difference between EMI and EMC Testing, and What Equipment is needed?

Because the terms ‘EMC’ and ‘EMI’ so often go hand in hand, it is important to understand the difference between the two. Whilst EMC stands for Electro Magnetic Compatibility, EMI stands for Electro Magnetic Interference. The names are not the only difference between the two, however.
EMI is related to how the product reacts to the interaction with other electrical items in the vicinity. EMC relates to how the product is compatible with the other electrical items as a whole. This means that an EMI test is almost always a part of an overall EMC test.

EMI and EMC Testing Equipment

Because of the difference between the two tests, there is obviously going to be a difference between the types of equipment used. However, because the EMI test is generally part of the EMC test, you will find that the equipment used for EMI is a part of the equipment used for the EMC as a whole. However, it is important to note the EMI and EMC testing equipment used will differ depending on the item you are using.

Choosing Your EMI and EMC Testing Equipment

There are a lot of variables to take into consideration when choosing your EMI and EMC testing equipment, power being the most obvious variable to spring to mind. When it comes to voltage meters, amplifiers and generators, and power sources in general, you will need to choose the one that best fits your requirement. There is no point in investing in equipment that produces 1000 volts when your item only uses 10 volts. Likewise, you don’t want to purchase equipment that doesn’t give you enough power.
Size is an important matter to note. You will need special labs to test your equipment in, and whilst you could use a small cupboard space to test a radio, you will need something far larger to test a jumbo jet.

EMI and Radiation

The main aspect of EMI testing is radiation. Therefore, EMI and EMC Testing Equipment will need to include antennas that determine how much radiation is being given out by your product. You will also need absorbers on your walls, floor, and ceiling. These will take your radiated energy and turn it into thermal energy which is far less harmful. The thermal energy will then be released back into the atmosphere, rather than being stored up and creating a high risk environment.

Are EMC and EMI Tests Really Necessary?

Whilst they are not are legal requirement, you should certainly consider investing in them. They are the best way to prove the compatibility, resourcefulness, and reliability of your product. This means, that you are more likely to get those funds you need from investors. You are also more likely to go on and sell. So whilst EMI and EMC testing equipment is expensive, and whilst the process as a whole can often cost you a pretty penny, it is definitely worth doing. Think of them as short term expenses which offer a much better opportunity for long term profit!