IEEE 741™ Amends Criteria to Protect Class 1E Systems and Equipment in Nuclear Power Generating Stations

IEEE 741™ Amends Criteria to Protect Class 1E Systems and Equipment in Nuclear Power Generating Stations

Standard revision is a collaborative effort with the Nuclear Energy Institute (NEI) to resolve longstanding conformance issues related to degraded voltage

PISCATAWAY, NJ, 12 October 2017 – IEEE, the world’s largest technical professional organization dedicated to advancing technology for humanity, and the IEEE Standards Association (IEEE SA), today announced the publication and availability of IEEE 741™ – Standard Criteria for the Protection of Class 1E Power Systems and Equipment in Nuclear Power Generating Stations. The standard provides the principal design criteria, design features, and testing requirements for the protection of Class 1E power systems and equipment. Revision to the standard identifies special protection features related to bus voltage monitoring design, commonly referred to as degraded voltage, providing a framework to ensure safe and efficient operational shutdown procedures in a power failover scenario.

“IEEE 741 is an extremely important milestone in helping the nuclear industry overcome longstanding issues related to degraded voltage conformance,” said Mark Bowman, chair, Protection of Class 1E Power Systems Working Group. “The standard revision meets current industry needs and shows how collaboration on defining policies and instituting best practices can help establish a foundation to address emergent regulatory requirements more quickly and effectively.”

For years, degraded voltage issues in nuclear power generating stations have been dealt with by utilities in piecemeal, resulting in increased downtime and higher overall costs to resolve problems identified during an audit. The revision to IEEE 741 culminates a concerted effort to pool the resources, expertise and guidance of IEEE SA, the Nuclear Energy Institute (NEI) and the Nuclear Regulatory Commission (NRC), and work towards conceptualizing a standard that defines methodologies to meet industry requirements and bring benefit to all stakeholders involved in safeguarding nuclear power generation.

“After a 41-year career in the nuclear industry, it is extremely rewarding to see IEEE 741 through to its fruition, as the core concerns have existed for at least 30 years,” said Steve Hutchins, senior project manager, NEI Degraded Voltage Task Force. “Because of thorough coordination between all the principals involved in developing the standard, we anticipate broad acceptance and endorsement of IEEE 741 that will help resolve current issues in a timely, cost-effective manner, and set the industry on course for more streamlined resolution of conformance issues moving forward.”

The publication of IEEE 741 adds to a wide range of standards, including IEC/IEEE 60780-323™, that support activities of the IEEE SA Conformity Assessment Program (ICAP), a partner to industry-leading test laboratories aimed at helping deliver robust conformity assessment programs based on IEEE standards. The IEEE Power & Energy Society (PES) Nuclear Power Engineering Committee (NPEC) and IEEE SA Conformity Assessment Program (ICAP) are actively engaged with device manufacturers, nuclear equipment qualification test laboratories, nuclear power plants and government regulators to develop a program for certifying standards compliance, and to bolster nuclear safety worldwide by aligning the global nuclear industry around best practices that ensure the safety of electrical equipment.

IEEE 741 is available for purchase at the IEEE Standards Store.

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About the IEEE Standards Association

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