ANSI C63.16: “Guide for Electrostatic Discharge Test Methodologies and Acceptance Criteria for Electronic Equipment”
ANSI C63.16 is a useful document meant to provide guidance for engineers and technicians conducting ESD testing to IEC 61000-4-2. Which means it is also useful for people testing to ISO 10605 and MIL-STD-461 CS118 by extension, since those documents are close to identical with the IEC standard. The 2016 version of C63.16 can be purchased here, but you might want to wait. A new version is expected to be published in late 2024/early 2025, which will have several technically substantial updates. I’m on the working group for this revision, so it’s near and dear to my heart.
Some of the topics addressed in C63.16:
Climate conditions during testing
The use of air vs. contact discharges
Test setups
Considerations for the ESD gun return cable
Considerations for the bleed resistors (in the revision, issues of degradation over time are raised)
Test procedures
Selecting test points
Handling large EUTs or those with complex peripheral arrangements
Approach speed for air discharges
In situ testing
Pin discharges
A lot of the guidance found in this document is based on decades worth of lessons learned. It points out things that are easy to miss until they go wrong.
TIP:
There have been a large number of cases where customers report issues in the field that hadn’t been caught and can’t be replicated in the lab. C63.16 aims to add to the minimum number of tests and test conditions called for in IEC 61000-4-2 in order to reduce these situations.
TIP:
The new revision contains an extensive discussion of relative humidity. Humidity can vary dramatically between indoors and outdoors, as well as different locations within a building, so knowing what the conditions are specifically where testing is occuring helps with repeatability. ESD events, in particular air discharges, are known to be sensitive to humidity conditions. On many occasions, the fact that equipment is used in environments far outside the 30 - 60% relative humidity called for by IEC 61000-4-2 is the cause for disconnects between field issues and lab testing as noted above.