Bob wrote;
>There is a actually a distinction between "insulator" and "dielectric", but
popularly
>they are interchangeable terms. Sometimes you want just an insulator
>without being a good (i.e., high) dielectric and sometimes you want both.
Dielectric properties are normally considered when dealing with higher
frequencies like vhf and uhf (i.e. radio and TV) but there are other
applications.
Higher dielectric valued materials tend to concentrate the electric field
lines to within the material (as opposed to air which has a low dielectric
value of 1.0). Sometimes dielectric grease is used in high current dc
contact applications (golf cart speed switches) as an arc suppressor. It
also has a very high melting or drip point temperature.
Cullen Bennett
Tempe, Arizona USA
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