First Trip Analysis

1. First Trip Analysis Chugach Electric Presented by: Steven Cannon, Substation Lineman

2. Chugach Overview • Alaska’s largest electrical utility • Provides generation, transmission, and distribution services • Generation mix 90% gas, 10% hydro • 65,000 members

3. Chugach System • 230kv-12.4kv lines • 50 substations and switchyards • 87 power transformers • 323 circuit breakers

4. Alaskan Rail Belt • The Alaska Railbelt system • Electrically Islanded • The Railbelt system • 850 MW Peak • Four generation areas: Fairbanks, Anchorage, Beluga, and the Kenai Peninsula. • The Anchorage area • Anchorage and Beluga generation • Tied to both the Fairbanks and Kenai Peninsula systems through single transmission ties • 138 kV tie north to Fairbanks • 115 kV tie south to the Kenai.

7. Why First Trip Analysis? • Analyze breakers “in the field” condition

8. Lubrication • Grease is composed of soap and oil • Oil provides lubrication • Soap gives consistency to hold lubrication • Oil eventually separates from the soap • Time causes soap to harden and gum up • Harden soap slows down breakers

9. Advantages of Capturing First Trip • Breaker can be tested in energized state • Test can be performed in about 10 minutes • Overlay breaker operations

10. Qualifications for Operator • Know how to read breaker control schemes • Be qualified to switch • Be computer literate • Understand safety rules for working in a substation

11. Connections

12. latch Trip Coil Plunger

13. Interpreting Graphs

14. Breaker 1616

15. Breaker 1616 DC Prints CC Amp Probe DC (+) DC (-) TC Amp Probe

16. DC Leads CT Leads

18. Main Bearings

19. Latch Bearing

20. Breaker 1616 Results

21. Important Tips • Change batteries often • Come to the breaker prepared • Label wires to apply leads • Catch the first trip • Catch multiple breaker operations • Save each shot before moving the Profile • Periodically upload shots to computer • Develop a backup plan

22. Questions?