1. BS EN 61109. Insulators for overhead lines. Composite suspension and tension insulators for a.c. systems with a nominal voltage greater than 1 000 V. Definitions, test methods and acceptance criteria. (11th May 2022) Authors: British Standards Institution, Record Type: Book Extent: 1 online resource (51 pages) View Content: Available online (eLD content is only available in our Reading Rooms) ↗