IEEE C37.105-2010 IEEE Standard for Qualifying Class 1E Protective Relays and Auxiliaries for Nuclear Power Generating Stations.
4. Qualification requirements The manufacturer and users of Class1E protective relays and auxiliaries are required to provide assurance that such equipment will meet or exceed its specific performance requirements throughout its installed life. This is accomplished through a quality assurance program that includes, but is not limited to, design, qualification, production quality control, installation, maintenance, and periodic testing. This standard treats only the qualification portion of this program. The purpose of the qualification program is to provide assurance that the protective relays and auxiliaries are capable ofperforming their required Class 1E function(s) before, during, and after the postulated DBE(s) specified for that equipment. Qualification may be accomplished in several ways: testing, analysis, previous operating experience, or a combination ofthese. This standard provides qualification procedures for both testing and analysis. Ongoing qualification may be used to extend the qualified life. With all qualification methods, the end result is that the final documentation verifies that the protective relay or auxiliary is capable ofperforming its required function. The documentation shall be in a form that allows auditing by competent personnel other than the qualifiers. It shall contain the performance requirements, the qualification method and procedure, the results, and justification for assumptions used in the qualification program.
5. Principles of qualification The qualification principles of Class 1E equipment for nuclear power generating stations are specified in IEEE Std 323. These principles shall be observed for the qualification of Class 1E, protective relays, and auxiliaries.
The fundamental requirement inherent to these principles is to provide assurance that the equipment is capable of performing its required Class 1E function(s) before, during, and after the postulated DBE(s) specified for that equipment. Such demonstration requires a documented qualification program that includes both an aging evaluation and a performance evaluation. The aging evaluation must first include identification of potential aging failure mechanisms of that equipment. When potential aging failure mechanisms are present, the qualification program must include both aging and performance evaluations coupled to show safety function performance capability for the specified DBEs. A qualified life, as defined in IEEE Std 323, must be assigned. Because the typical life of a nuclear power plant is forty years, a desired but not required qualified life is in excess offorty years.IEEE C37.105 pdf download.