Sorry for resurrecting my own thread.

I am still wondering if there is an "accepted" test setup for ESD testing on a DC-DC power adapter. This is something I can ask our EMC lab about too...but I've found it difficult to get clear information from them, since they are located in China.
Since an isolated AC-DC converter feeds the DC-DC DUT, it's hard for me to separate what part of our issue might be related to the DUT and what might be related to the DC source. The DC source maintains good regulation throughout the ESD event, but since the DUT is a Class II (double insulated) converter, I imagine that the ESD return path is somehow through the DC source (which is an AC-DC converter ). If we consider the DC source as "part of the DUT" then I'd imagine there could be a lot of variability in the test, depending on the lab and the source they use. The ESD return impedance to earth might be quite variable for different DC sources, I'd expect.
At the end of the day, the unit should function well during the ESD event, regardless of what the source looks like, but I am still wondering if there's something more concrete I can refer to, for this particular situation.
Thanks a lot.