Difference between Immunity and susceptibility or they are same?

Susceptibility, is the tendency of electrical equipment, referred to as the victim, to malfunction or break down in the presence of unwanted emissions, which are known as Radio frequency interference (RFI).

Immunity is the opposite of susceptibility, being the ability of equipment to function correctly in the presence of RFI.

My personal view : There are some websites which explains that Immunity & Susceptibility are same but it may or may not.

In case of Automotive standards it is Radiated immunity as per ISO 11452-4 because automotive cars are directly related to human safety so DUT should not malfunction during the testing otherwise it could be fatal.

For ex. Headlamp intensity flickering may cause visibility issues in night time.

In case of Household equipment standards it is Radiated susceptibility as per IEC 61000-4-3 because household equipment’s may not cause death to human beings it only provide the discomfort or annoyance to user.

For ex. TV or Radio fluctuations may cause annoyance.

It is debatable topic because many DUT’s in ISM (Industrial, Scientific & Medical) Equipment’s which may are related to human safety & many DUT’s are in automotive are not related to Human safety like infotainment system or comfort related functions.

Reference - https://en.wikipedia.org/wiki/Electromagnetic_compatibility

A complicated & difficult subject ????

When you listen this word first question comes in your mind is what is EMC?

EMC – Electromagnetic Compatibility

EMC is the ability of electrical equipment and systems to function acceptably in their electromagnetic environment.

In Simple words – Do not disturb others & do not get disturb by others (In this case electronics equipment only)

Basic definition of EMC is

                                              EMC = EMI + EMS 

EMI - Electromagnetic interference/Emission (Do not disturb others)

EMS - Electromagnetic Susceptibility/Immunity (Do not get disturb by others) 

                                   Emission.                                 Immunity 

 

EMC testing is subdivided into following types :-