Is it possible that the technical requirement was included in the original
spec to specifically proscribe the use of the materials that you have employed?

I am familiar will the random inclusion of requirements at the specification
stage. You have to be careful in spotlightnig them and, where possible,
weeding them out. Often the client may be unaware of the cost/technology
implications/limitations of the single line of the specification.

250V doesn't strike me as a 'high voltage' for bias testing passive
hardware, regardless of the preconditioning applied. If the preconditioning
implies a requirement for the physical design's voltage withstand to be
derated to
150v/mil, then so be it. The potential for the real practical degradation or
decomposition of insulating materials is obviously what is being addressed.

If the test is unreasonable, given the obvious expectations of the client re
current competitive commodities in end-market use, it may be profitable to
make a comparative exposition of this available to the client.

For telecom safety, components and full assemblies see a 'proof test' across
isolation barriers, albiet after only 48 hours at room temperature and
93%RH. (Extending this test to >300 hours hasn't produced variations in test
response, in my experience.) This requirement drives the selection of
materials and the construction methods used.

RL

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