P37.102: Circuit Breaker Life Management

Development of an Intelligent Assistant for Maintenance and Troubleshooting aims to investigate advanced techniques and technologies to facilitate the efficient capture of expert knowledge and its onsite presentation to support field personnel. The intent is to help field personnel understand and assess circuit breaker condition, identify problems, and perform appropriate maintenance more efficiently and effectively. Planned work in 2026 intends to scope the problem through exploratory work, and development of a research approach.

Effect of Component Degradation on Circuit Breaker Operation intends to characterize possible consequences of degraded components on circuit breaker operation (for example, slow trip, abnormal mechanism wear, lubrication, compressor/pump failures) with the following:

• Catalog failure reports and other information available from circuit breaker failure events and/or utility root cause analysis
• Catalog utility experiences of using digital relays for circuit breaker diagnostics
• Update the EPRI circuit breaker lubrication selection and application guide, first published in 2015, by assessing the performance of fluorosilicone grease through laboratory testing of field-aged bearings and incorporation of the findings (confirm whether the estimated life based on accelerated aging tests was accurate)

Circuit Breaker Online Monitoring Effectiveness Assessment aims to develop and apply assessment metrics to various circuit breaker online monitors to determine which monitors and tests provide the most useful information. The objective is to provide information to assist in monitor application and specification. Tasks in 2026 plan to:

• Work with funders to identify specific circuit breaker monitors of the highest interest and use publicly available information to perform systematic investigations to understand what capabilities are claimed, make comparisons, and assess their applicability
• Continue monitor testing in EPRI laboratories, when possible, to confirm that monitor measurements match comparable offline tests—for example, breaker timing
• Document utility experiences with online monitors
• Maintain awareness by scouting commercially available and emerging monitor technologies

Circuit Breaker Diagnostics Effectiveness Assessment intends to develop and apply metrics to assess the effectiveness of various noninvasive online and off-line circuit breaker diagnostic techniques. Tasks in 2026 plan to:

• Expand efficacy assessments beyond dynamic resistance measurements (DRM) to additional techniques, for example, acoustics and partial discharge
• Maintain awareness by scouting commercially available and emerging technologies

Assess the efficacy of SF6 gas analysis in determining interrupter component condition.

• Tasks in 2026 intend to conduct the state-of-the-science literature review to understand current state and assess gaps.

Leak Sealing for Circuit Breakers and Gas-Insulated Substations investigates methods that utilities can use to cost-effectively seal dielectric gas (SF6 and non-SF6) leaks. The emphasis is on identifying materials and techniques that can seal while maintaining equipment operating pressures and are easy for utility personnel to apply and remove. Novel techniques for sealing SF6 leaks on circuit breaker and GIS component geometries at ground potential were developed, and three successful techniques identified in the laboratory are in field tests at 10 utility sites. Tasks in 2026 plan to:

• Continue monitoring the performance of the existing and new field trials
• Develop application guides and “how-to” videos for techniques utilizing the learnings from field trials and make them available through the Transmission Resource Center (TRC): Circuit Breaker Life Management | Circuit Breaker Life Management (epri.com)
• Continue investigations to find sealants that cure at lower temperatures
• Scout innovative methods used by others and investigate whether they can be used for sealing breaker and GIS leaks
• Develop techniques for additional geometries, for example, 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
• Initiate a new effort to investigate:
  • Challenges that may be encountered in sealing leaks of SF6 alternatives
  • Applying techniques successful in sealing SF6 to SF6 alternative gases
• Circuit Breaker Reference Guide. There are plans to continue developing a comprehensive reference on circuit breaker procurement, operation, maintenance, and life-cycle management to serve as a resource for less experienced personnel. The goal is to develop a guide that provides information on fundamental design descriptions, operation, selection, and application principles, maintenance, monitoring, and replacement and captures the knowledge of leading circuit breaker experts. To date, nine sections have been written, including sections on circuit breaker installation, diagnostics, problem and failure investigation, lubrication, pump and compressor maintenance, specifications and procurement, and interrupter cleaning. New works aims to:
  • Develop guidance material for performing factory visits and design reviews for SF6 circuit breakers
  • Develop content on emerging circuit breaker technologies such as non-SF6 circuit breaker technologies
  • Make the reference guide available through the Transmission Resource Center (TRC): Circuit Breaker Life Management | Circuit Breaker Life Management (epri.com)

Technical Webinars on the Circuit Breaker Guidebook intends to develop and host a series of technical webinars based on sections in the Circuit Breaker Guidebook. Content may be selected to accelerate learning on key topics in the Circuit Breaker Guidebook for those with less circuit breaker experience. Webinar material will be published for continued and convenient future access.

Circuit Breaker Mechanism Maintenance Guides. Maintenance supplements written for specific breaker models serve as training tools and guidance for proper mechanism field disassembly, cleaning, lubrication, and reassembly. Gaining importance as experienced personnel retire, the guides communicate information in step-by-step illustrated tasks, cover material not included in manufacturers’ instruction manuals, can be readily incorporated in a utility’s maintenance procedure, and have been developed for 11 models. The intent is to expand the library with new guides annually. Model selections plan to be prioritized based on advice from the task force. EPRI plans to provide the guides through the Transmission Resource Center (TRC): Circuit Breaker Life Management | Circuit Breaker Life Management (epri.com)

High-Voltage Circuit Breaker (HVCB) Life Management Workshop proposes an annual workshop that plans to include tutorials on the material contained in the project’s products, presentations on utility experiences, and examples of the application of the project’s results.