High Voltage power supplies and insulation depreciation?

[cupoftea]

Hi,
Is it true that HV SMPS...eg Vout = 15kV+ suffer from wear out of their insulation, and so have a limited lifetime?
I remember working in one HV SMPS place, and the Chief Engineer said...its not if they fail...its when.
I am pretty sure they had one HV PSU that had , on average , a one year lifetime, and it simply wasnt cost-effective to try and improve this.

 

[FvM]

Correctly designed HV insulation is free of partial discharge and achieves lifetime similar to other professional equipment, e.g. 10 years and more.

 

[Easy peasy]

tracking and eventual breakdown or discharge / partial discharge are very dependent on ambient temps, humidity, and the use of proper materials for potting etc to prevent the above ...