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Insulator Bil Ratings: 138KV
Substation insulator BIL (Basic Insulation Level) ratings, BSL, creepage distances and arcing distances by nominal voltage class per IEEE C37.30 and NESC Rule 235. Covers 15kV through 765kV.
| voltage class | applicable standard | bil kV crest (kV) | bsl kV crest (kV) | dry arcing distance in (in) | min creepage in (in) | typical insulator height in (in) |
|---|---|---|---|---|---|---|
| 138KV | IEEE C37.30 / NESC Rule 235 | 650 | 540 | 46 | 36 | 38 |
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