Overview & Events

Circuit Breakers Online Monitoring Effectiveness Assessment develops and applies assessment metrics to various circuit breaker online monitors to determine which monitors and tests provide the most useful information. The objective is to provide utilities guidance on the most informative and cost-effective procedures for nonintrusive diagnostics to support condition-based maintenance. Efforts to date have identified commercially available as well as emerging technologies and documented the claimed capabilities as well as utility experience from using specific online monitors. Based on the findings a plan has been formulated to evaluate their effectiveness. Efforts in 2024 intend to work with funders to identify specific circuit breaker monitors of the highest interest and implement the evaluation approach to make comparisons and assess their efficacy. If successful, the results provide valuable assistance in monitor specification, reliability, interpretation, and adoption.

Circuit Breakers Diagnostics Effectiveness Assessment develops and applies metrics to assess the effectiveness of various circuit breaker diagnostic techniques. The objective is to provide utilities guidance on the most informative and cost-effective procedures for nonintrusive diagnostics to support condition-based maintenance.

• Assessing the efficacy of circuit breaker dynamic resistance measurements (DRM): Work is underway to assess the effectiveness of DRM, an offline non-intrusive diagnostic test to assess the condition of circuit breaker interrupter arcing contacts. Laboratory tests performed to date demonstrate the technique’s ability to detect artificially degraded contacts. Laboratory and field tests continue in 2024 to determine the relationship between the DRM waveform and contact condition and build a library for different circuit breaker interrupter models.

• Efforts in 2024 also intend to expand efficacy assessment to other techniques, for example, X-Rays, Timing and Travel etc. and explore opportunities to utilize relays for circuit breaker monitoring.

SF6 Leak Sealing for Circuit Breakers and Gas-Insulated Substations investigates methods that can be used by utilities to cost-effectively seal SF6 leaks. The emphasis is on identifying materials and techniques that can seal while maintaining equipment operating pressures and are easy to apply and remove by utility personnel without having to resort to outside service providers, clamps, or molds. Efforts to date have developed novel techniques for sealing leaks on circuit breaker and GIS component geometries at ground potential. For example, leaks in porous wields, o-rings in flange and threaded fittings. Three successful techniques identified in the laboratory testing are being tested in the field at utility sites. Efforts in 2024 intend to:

• Develop techniques for other geometries. For example, leaks in the bushing flange interface. Some of these new geometries may not be at ground potential.

• Investigate scaling application of existing techniques to larger flange diameters.

• Continue search for innovative methods used by other industries.

• Continue investigations to find sealants that cure at lower temperatures.

• Monitor the performance of the field trials.

• For techniques that are successful in the field develop application guides and “how-to” videos.