Sulphur Hexafluoride Circuit Breakers

James R. White, Shermco IndustriesColumns, Spring 2019 Columns, Tech Quiz

Sulphur hexafluoride circuit breakers used to be the domain of utilities, but they are liable to be used now by any large- or medium-size industrial. This Tech Quiz will review some of the NETA standard requirements for these circuit breakers.

1. In ANSI/NETA ATS, which ANSI/IEEE standard is referred to if manufacturer’s data is not available?

a. C57.04

b. C57.11

c. C37.04

d. C37.11

2. What is considered an acceptable value for air in the gas?

a. 0.03 percent (300 ppmw)

b. 0.05 percent (500 ppmw)

c. 0.07 percent (700 ppmw)

d. 0.09 percent (900 ppmw)

3. Which method is used to test for air in the gas?

a. ASTM D2029

b. ASTM D2284

c. ASTM D2685

d. ASTM D2681

4. How much leakage is allowed per the ATS test values?

a. 0

b. 0.5ppm over 3 months

c. 0.5ppm over 6 months

d. 0.05 percent over 6 months

5. The power factor of bushings is to be within ____________ percent of nameplate.

a. 3 percent

b. 5 percent

c. 7 percent

d. 10 percent

6. What are the two types of SF6 circuit breakers?

a. Bused and un-bused

b. Extended tank and compact tank

c. Spring and pneudraulic

d. Dead tank and live tank



James (Jim) R. White, Vice President of Training Services, has worked for Shermco Industries Inc. since 2001. He is a NFPA Certified Electrical Safety Compliance Professional and a NETA Level 4 Senior Technician. Jim is NETA’s principal member on NFPA Technical Committee NFPA 70E®, Standard for Electrical Safety in the Workplace®, NETA’s principal representative on National Electrical Code® Code-Making Panel (CMP) 13, and represents NETA on ASTM International Technical Committee F18, Electrical Protective Equipment for Workers. Jim is Shermco Industries’ principal member on NFPA Technical Committee for NFPA 70B, Recommended Practice for Electrical Equipment Maintenance and represents AWEA on the ANSI/ISEA Standard 203 Secondary Single-Use Flame Resistant Protective Clothing for Use Over Primary Flame Resistant Protective Clothing. An IEEE Senior Member, Jim received the IEEE/IAS/PCIC Electrical Safety Excellence Award in 2011 and NETA’s Outstanding Achievement Award in 2013. Jim was Chairman of the IEEE Electrical Safety Workshop in 2008 and is currently Vice-Chair for the IEEE IAS/PCIC Safety Subcommittee.