Breakdown voltage moisture tolerance
Moisture can have two main forms of
existence in insulating liquids: dissolved or
free water. Polar fluids tend to form hydrogen
bonds with water molecules so that water
can dissolve easily. This is why polar fluids
have significantly more water tolerance.
On the other hand, non-polar mineral oil
and slightly polar silicone oil is particularly
sensitive to the absolute moisture content.
Fig. 2 shows the breakdown voltage at