للكاتب
E.A. EISAWY
Operational Safety Dept., National Center for Nuclear Safety
ABSTRACT
The important deterioration phenomenon for the insulators is electrical damage to its surface
in the presence of high humidity and contamination, possibly aggravated by high radiation
doses. A model has been developed which predicts, the probability of an electrical breakdown
for different temperatures and protective measures. In this model, breakdown proceeds in
three steps: (i) breakdown current which determines the irreversible onset of breakdown, (ii)
average leakage current, i.e., time averaged and experiment averaged for each essential
parameter combination, and (iii) the probability of complete breakdown which is the ratio of
average leakage current to breakdown current. Expressions for each of these steps have been
introduced. In part of the experiments, a protective enclosure with a small weepholes has been
provided for the insulating terminal blocks of the wiring system of the reactor. The
experimental breakdown probabilities for protected and for unprotected terminals have been
calculated.
That saves me. Thanks for being so sesnilbe!