Variable Frequency Drives: failures & contamination 1

[Ants]

I work for a chemical plant with an inherently corrosive atmosphere. I have a large base of new technology (4 years oldest)VFD's. Over the past year we experienced an abnormally high rate of failures, mostly related no non-power elements (gate driver boards, rectifier drives boards comms cards etc..)
At first earthing was suspected as a possible problem, but contamination/corrosion are emerging as the biggest suspect.
Now, the cards are coated except for one place: where IC's/microchips fit into sockets. Our main sources of contamination are sulphur and ammonia related chemicals.
Can one coat these as well to prevent corrosion, and with what?

 

[jbartos]

Suggestion: Try a thin film of the epoxy glue.

 

[teco]

ants:- had a same problem only in a geothermal area.
we used a sterling 009-0008 anti fungal-anti tracking spay on air dry varnish.we understand dolph also produce a spray on air dry varnish.
kind regds.