Document: NRC Regulatory Guide
Document ID: cdc706d5-60ed-40a4-b55a-9771904107a7
Document Type: regulatory_guide
Title: Seismic Qualification of Electric and Mechanical Equipment for Nuclear Power Plants (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1809/ML18093A675.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.100
CFR Part: 
CFR Title: 

Content:
ssued July 1997 (Ref. 24). In response to the new information on ac-powered MOV performance, Limitorque updated its guidance in Technical Update 98-01, “Actuator Output Torque Calculation,” issued May 1998, and in Supplement 1 to Technical Update 98-01, issued July 1998 (Ref. 25), for the prediction of ac-powered MOV motor-actuator output. The NRC alerted licensees to the new information on ac-powered MOV output in NRC Information Notice 96-48, “Motor-Operated Valve Performance Issues,” Supplement 1, dated July 24, 1998 (Ref. 26). Following its review of ac-powered MOV performance, the NRC conducted research to study the performance of Limitorque direct current (dc)-powered MOV motor actuators under various temperature and voltage conditions. NUREG/CR-6620, “Testing of dc-Powered Actuators for Motor-Operated Valves,” issued May 1999 (Ref. 27), documents this research. In June 2000, the BWR Owners Group forwarded to the NRC its TR-NEDC-32958, “BWR Owners’ Group DC Motor Performance Methodology—Predicting Capability and Stroke Time in DC Motor-Operated Valves,” issued March 2000 (Ref. 28). In August 2001, the NRC issued Regulatory Issue Summary (RIS) 2001-15, “Performance of dc-Powered Motor-Operated Valve Actuators” (Ref. 29), to inform licensees of the availability of improved industry guidance for predicting dc-powered MOV actuator performance. For power-operated valves other than MOVs, many lessons learned from MOV testing and performance are applicable to valves operated by other types of actuators. The NRC issued RIS 2000-03, “Resolution of Generic Safety Issue 158: Performance of Safety-Related Power-Operated Valves under Design-Basis Conditions” (Ref. 30), to provide guidance for programs to verify the design-basis capability of power-operated valves at NPPs. In RIS 2000-03, the NRC staff indicated that it would continue to monitor licensee activities to ensure that power-operated valves are capable of performing their