I manage a fleet of large UPSes in industrial plants across the UK.
Over the past couple of years, I have had a few blow up. The manufacturer, who also maintain the UPSes once a year, claim that the levels of dust (including concrete dust in new buildings, apparently) are to blame, and that this dust corrodes UPS components, and can provide an electrically conductive path which can also cause electrical arcs.
I am just wondering if there is any definitive standard or guidance on managing the risks of dust and dirt on large power electronics?
So far I have managed to identify IEC 60721-3-2 which covers environmental parameters, (mentioned in document below for storing and handling IGBTs and thyristors).
I don't think 60721-3-2 covers the electrical risks of the environment however, so I am not sure if it tells me anything useful about my specific problem.