Air discharge and contact discharge method

[Dummy]

From what I understand, contact discharge is applied directly to the
conductive surfaces of EUT and coupling planes. While air discharge is
applied to insulating surfaces and NOT conductive surfaces. Are the
statements above absolute?

There's one case where a radio failed when zapped with 15kV by using
air discharge method at CONDUCTIVE surface. The argument was that the
radio shouldn't be exposed to 15kV at conductive surface. It should be
using the contact discharge method instead.

I'm trying to find some documents to support the above fact - that air
discharge can't be applied to conductive surface, but to no avail. Can
somebody shed some light?

 

[mike]

Dummy wrote:

From what I understand, contact discharge is applied directly to the
conductive surfaces of EUT and coupling planes. While air discharge is
applied to insulating surfaces and NOT conductive surfaces. Are the
statements above absolute?

There's one case where a radio failed when zapped with 15kV by using
air discharge method at CONDUCTIVE surface. The argument was that the
radio shouldn't be exposed to 15kV at conductive surface. It should be
using the contact discharge method instead.

I'm trying to find some documents to support the above fact - that air
discharge can't be applied to conductive surface, but to no avail. Can
somebody shed some light?

I understand you have to pass some standard.
BUT
If you can kill the product by walking up and zapping it, you're not
done. Your customer won't really care whether he touched metal or
plastic. He just cares that it's broke.
Standards are no substitute for common sense and good design practice.
mike

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