361 / | HD | ELECTRICITY: ELECTRICAL SYSTEMS AND DEVICES |
1 | DF | SAFETY AND PROTECTION OF SYSTEMS AND DEVICES {32} |
117 | DF | .~ High voltage dissipation (e.g., lightning arrester) {10} |
131 | DF | .~.~ Combined (e.g., with disconnect switch) {1} |
132 | .~.~.~ With line supporting insulator |