| 324 / | HD | ELECTRICITY: MEASURING AND TESTING |
| 500 | DF | FAULT DETECTING IN ELECTRIC CIRCUITS AND OF ELECTRIC COMPONENTS {10} |
| 537 | DF | .~ Of individual circuit component or element {17} |
| 539 | ![]() | .~.~ Multiconductor cable {3} |
| 540 | DF | .~.~.~> With sequencer |
| 541 | DF | .~.~.~> For insulation fault |
| 542 | DF | .~.~.~> Having a light or sound indicator |