skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: An assessment of fire vulnerability for aged electrical relays

Technical Report ·
DOI:https://doi.org/10.2172/46674· OSTI ID:46674
 [1];  [1]
  1. Sandia National Labs., Albuquerque, NM (United States)

There has been some concern that, as nuclear power plants age, protective measures taken to control and minimize the impact of fire may become ineffective, or significantly less effective, and hence result in an increased fire risk. One objective of the Fire Vulnerability of Aged Electrical Components Program is to assess the effects of aging and service wear on the fire vulnerability of electrical equipment. An increased fire vulnerability of components may lead to an overall increase in fire risk to the plant. Because of their widespread use in various electrical safety systems, electromechanical relays were chosen to be the initial components for evaluation. This test program assessed the impact of operational and thermal aging on the vulnerability of these relays to fire-induced damage. Only thermal effects of a fire were examined in this test program. The impact of smoke, corrosive materials, or fire suppression effects on relay performance were not addressed in this test program. The purpose of this test program was to assess whether the fire vulnerability of electrical relays increased with aging. The sequence followed for the test program was to: identify specific relay types, develop three fire scenarios, artificially age several relays, test the unaged and aged relays in the fire exposure scenarios, and compare the results. The relays tested were Agastat GPI, General Electric (GE) HMA, HGA, and HFA. At least two relays of each type were artificially aged and at least two relays of each type were new. Relays were operationally aged by cycling the relay under rated load for 2,000 operations. These relays were then thermally aged for 60 days with their coil energized.

Research Organization:
US Nuclear Regulatory Commission (NRC), Washington, DC (United States). Div. of Engineering Technology; Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)
Sponsoring Organization:
Nuclear Regulatory Commission, Washington, DC (United States)
DOE Contract Number:
AC04-94AL85000
OSTI ID:
46674
Report Number(s):
NUREG/CR-6220; SAND-94-0769; ON: TI95009316; TRN: 95:010960
Resource Relation:
Other Information: PBD: Mar 1995
Country of Publication:
United States
Language:
English