Doug,
Whenever testing PC boards against the generic immunity standard we usually test as follows: The host PC's AC power supply for EFT (although it could be argued that since the board does not have an external power port the test is not required ??) ESD to the PC bracket of the card, to the PC chassis in the vicinity of the card, to the sides and top of the PC's enclosure (rationale being that the most likely ESD events in the vicinity of the card will be to the PC's enclosure), and to the coupling planes (if testing to IEC801-2:1991). Radiated immunity on the system. Interesting to see what everyone else is doing ??? Any news on EN55024 anyone ??? Mark Briggs >To demonstrate compliance of a computer option board with the EMC >Directive, EN 55022/A1 allows testing in a single compliant host for >emissions. Immunity testing is another matter, with the lack of a >harmonized ITE immunity standard. Is there any consensus or opinions on >the appropriate immunity testing on, for example, a video graphics >adapter? Using the generic residential immunity standard (EN >50082-1:1992), my take would be ESD to 8 kV air, 4 kV contact, in the >vicinity of the output connector. However, assuming video cabling to be >typically short (<3m) EFT testing would be performed only on the host >computer's AC input and RF immunity on the system. These latter tests >seem to be of limited value at best, but I cannot locate rationale for >their exemption. Any thoughts from the forum? > > >Doug Frazee
