IEEE 535-1986 (R1994) pdf free.IEEE Standard for Qualification of Class 1E Lead Storage Batteries for Nuclear Power Generating Stations.
IEEE 535 racks that have operated successfully can be considered qualified for equal or less severe service.Operating experience can provide information on limits of extrapolation, failure modes, and failure rate. The validityof operating experience as a means of qualification shall be determined from the type and amount of documentationsupporting the service conditions and the performance of the battery and rack during this time.
Qualification of the battery or the rack, or both, by analysis shall require the construction of a valid mathematicalmodel.The validity of the mathematical model shall be justified by test data, operating experience , or physical laws ofnature.Qualification shall consist of a quantitative analysis of the mathematical model that shall logically prove thatthe battery or the rack, or both, meet or exceed the equipment design specifications when subjected to the design basisevent. The data used to support the qualification of equipment by analysis shall be pertinent to the application and bein an auditable form.
ANSVIEEE Std 323-1983 [3],6.9, describes several methods of extending qualified life. Some examples of applyingthese methods are described below:
l) After a period less than the previously qualified life,randomly selected cells from the qualified battery shall be removed and replaced with new,qualified cells. The removed cells shall be subjected to anotherqualification test (including accelerated aging). Successful qualification of the removed cells will extend thequalified life of the battery.
2)At the time of the initial installation of the qualified battery, additional qualified cells shall also be installed in locations where they will be subjected to service and environmental conditions at least as severe as thoseof the initial battery.After a period less than the qualified life, cells shall be subjected to a qualification test(including accelerated aging).The new qualified life is then applicable to the initial installation.
3) Extension of qualified life by analysis should consider the service environment,battery condition as determined by maintenance, testing records, and manufacturer’s recommendations.IEEE 535 pdf download.