Introduction: The scope of the project covers the methods of monitoring the condition of cable insulation using the Online Gas-in-Oil (NIA_NGET0092) project to look for early internal insulation breakdown. The project will provide risk mitigation for a cable with a recent history of issues and has been repaired and may have a recurring defect. The learning through this project will provide information for policy on the technical and whole life value of retro-fitting sensors and/or methods to provide information for asset health and replacement prioritisation. This project is innovative because the work on condition monitoring of insulation breakdown has never been completed before.

Objectives:

To be able to provide online information on the state of insulation in HV cables installed on the Transmission system. 

Expected Benefits: This project will be successful if National Grid can quantitively monitor HV cable insulation.