Feb 2013
Electricity Distribution
Failure on Demand
Feb 2013
Northern Powergrid
Chris Goodhand, Innovation Manager (01977 605641)
Click here to send a question to the contact.
Innovation Funding Incentive
High Voltage Technology
This project has two key elements:

The forensic investigation of two AEI/ GEC BRVP17 and two South Wales C4X switchgear mechanisms will enable understanding of the degradation processes and the cause of the slow opening of the switchgear. The information obtained will assist in developing an appropriate strategy to ensure the reliability of the remaining population of assets, with the objective of reducing the rate of failure on demand incidents. Learning on asset degradation will also feed into our decision support tools developed on the Condition Based Risk Management (CBRM) platform.

The production of an approved New Product Specification, supported by field trials, for retrofit AEI/ GEC BRVP17 and South Wales C4X circuit breakers will provide a cost-effective alternative solution to replacing a whole switchboard where one or two individual units are identified to have unacceptable performance that cannot be rectified through maintenance.

To carry out forensic analysis of the moving portion of a total of four sample circuit breakers (two South Wales switchgear type C4X and two AEI/ GEC type BVRP17), to include intrusive examination of the mechanism and analysis of the lubricants applied. The work will be caried out by a third party and will comprise the following key activities:

  • Analysis of background information, including previous trip timing profiles and maintenance procedures

  • Completion of three consecutive trip-timing profiles on each circuit breaker

  • Visual examination and photography in the as received condition

  • Detailed examination of the mechanism to determine the general condition and identify any degradation, condition of lubricants, corrosion, wear, alignment etc.

  • Removal of lubricant from mechanisms to assess condition with regard to the ability to lubricate adequately

  • Dismantling of mechanism as required

  • Optical and electron microscopy of components as required

  • Compilation and issue of report.

To facilitate the removal of switchgear moving portions for analysis and to provide NPG with approved retrofit moving portions as an alternative option to replacing a whole switchboard where failures are confined to one or two specific units, it is proposed to specify, assess, purchase, retrofit install and trial two AEI/ GEC BVRP17 moving portions and two South Wales switchgear C4X units.