IEEE 1205-2000 pdf free.IEE Guide for Assessing,Monitoring, and Mitigating Aging Effects on Class 1E Equipment Usedin Nuclear Power Generating Stations.
IEEE 1205 The purpose of this guide is to supplement existing IEEE nuclear standards in assessing aging degradationeffects. The methods described herein can be used to identify the performance capability of Class 1Eequip-ment beyond its qualified life.
lt is intended that the user determine the specific equipment that warrants attention using this guide. It is notintended that the methods described herein be required to be applied to all Class 1E equipment.For example,if aging considerations have been satisfactorily addressed through other means (e.g., equipment qualifica-tion), then use of this guide may not be warranted.Similarly, for some equipment, only partial application ofthis guide may be warranted.
Aging assessment may be pursued in response to a variety of factors,e.g., regulatory guidance, approachingobsolescence, reduced availability or reliability, or for life extension.For example, IEEE Std 323-1983′ pro-vides definitive guidance for the qualification of Class 1E equipment required to mitigate the consequences ofa design basis event.Such factors plus economics also affect the method and extent of aging assessment actu-ally performed.Monitoring and/or mitigating the aging of some equipment may be determined to be less costeffective than replacing the equipment. Running to failure may be an option under certain special situations.A stressor that stems from fabrication, preservice, or service conditions may produce aging mechanisms andeffects or immediate degradation of Class 1E equipment. The following two types of stressors should beconsidered for aging:
Environmental. These are stressors that exist continuously in the environment surrounding theequipment, whether it is operating or shut down. Examples include vibration, heat, radiation, andhumidity.Annex A provides a representative listing of stressors and their effects, while Annex B pro-vides considerations for environmental monitoring.
b)Operational.These are stressors arising from equipment operation. Examples are internal heating from electrical or mechanical loading, physical stresses from mechanical or electrical surges, vibra-tion, and abrasive wearing of parts.
The aging degradation of electrical equipment is usually be a function of the duration, range and intensity ofstressors experienced by the equipment. Aging degradation due to a single stressor may usually be repre-sented as a simple first-order relationship involving stressor intensity and time; however, aging degradationdue to a combination of more than one stressor may exceed the sum of the individual effects.IEEE 1205 pdf download.