Lesson 4/1040%
MODULE 04

IEC 61000-4-2, Test Levels & Discharge Types

IEC 61000-4-2 is the core international standard for system-level ESD immunity testing. It defines the generator circuit, the test levels, two distinct discharge methods, and the pass/fail performance criteria your product will be judged against.

Learning Objectives

📖
Understand the scope of IEC 61000-4-2
🔢
Read the standard's four severity levels
🔀
Distinguish contact vs. air discharge
✅
Apply the four performance criteria (A-D)

IEC 61000-4-2 is part of the broader IEC 61000-4-x family of immunity test standards. It specifies a standardized ESD generator (the "ESD gun"), a defined 150 pF / 330 O discharge network, test setups for both tabletop and floor-standing equipment, and the number/spacing of discharges required at each test point. Product-family standards (medical, automotive, industrial, and so on -- covered in Module 06) reference IEC 61000-4-2 and specify which severity level and performance criteria apply to that product category.

IEC 61000-4-2 is a basic standard -- it defines the test method itself, not the pass/fail levels for any specific product. Those come from the product-family or generic standard that references it (for example IEC 60601-1-2 for medical devices).
Level Contact Discharge Air Discharge
1 2 kV 2 kV
2 4 kV 4 kV
3 6 kV 8 kV
4 8 kV 15 kV

Contact discharge is the preferred test method wherever a conductive surface is accessible, precisely because it is more repeatable. Air discharge is reserved for surfaces that are not conductive (plastic housings, display glass) and, because it depends on the exact speed and geometry of the approaching probe, its levels are defined higher and its results are inherently less repeatable than contact discharge.

4 kV
Common consumer-product baseline (Level 2 contact)
8 kV
Common medical/industrial baseline (Level 3-4 contact)
15 kV
Highest standard air-discharge level (Level 4)

Animated: Probe Approach & Discharge

A labeled, to-scale illustration of an operator's gloved hand gripping the ESD gun by its pistol-style handle, triggering a discharge into the EUT. (Built as a detailed illustration rather than a licensed stock photo, so it can be freely reused and kept perfectly in sync with the animation below.)

Criterion Definition
A Normal performance within specification during and after the test, no observable effect
B Temporary loss of function or degradation that self-recovers without operator intervention
C Temporary loss of function or degradation requiring operator intervention (e.g. a power cycle) to recover
D Loss of function that is not recoverable due to damage to hardware, software, or loss of data -- generally not acceptable
Which criterion is acceptable (A, B, or C) is defined by the product-family standard and the manufacturer's own performance specification -- IEC 61000-4-2 itself does not mandate a pass level. Criterion D is essentially always a fail.
KNOWLEDGE CHECK

Module 4 Quiz

Score: 0 / 10

Select the best answer for each question. Instant feedback is provided after each response.

Question 1 of 10