Almost all of us would have heard the term EMC in some way or the other. EMC, by itself stands for Electromagnetic Compatibility. The intention behind EMC is to make sure all Electrical equipment situated close to each other will work as designed without causing Electromagnetic disturbance to each other.

All commercial, industrial and even military grade products need to have EMC clearance in order to be manufactured and used. Commercial products generally tend to have a relaxed EMC specification when compared to Industrial and Military products.

EMC can be split into two major categories – Emissions and Immunity. Emissions are classified as electromagnetic waves originating from the product that could potentially harm the neighbouring products or equipments.

Immunity on the other hand is defined as electromagnetic noise originating from an external product that could harm the product under consideration. In short, Emission tests check how much noise is generated from a product and immunity tests check how much incoming noise will affect the product’s functionality.

Emissions and Immunity measurements should co-exist. It wouldn’t mean much if the product passes just one of them. The emission limit is generally many thousands of folds lesser than the immunity limit.

This type of limiting ensures that there is very less possibility for a product to emit enough to disturb the neighbours. Also the higher limits for immunity means that neighbours are generally capable of handling much higher noise than what is being emitted by one product.

Both Emissions and Immunity can further be divided into two sub categories – Conducted and Radiated, forming the four most important components of EMC – Radiated Emissions, Conducted Emissions, Radiated Immunity and Conducted Immunity.