Document: NUREG-0800
Document ID: c81bfd3b-114e-4701-a558-e08d57d14fd5
Document Type: srp
Title: D provides additional guidance.
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1515/ML15159A769.pdf
Revision Date: 2023-06
Chapter: 7
Section ID: 7.1
CFR Part: 
CFR Title: 

Content:
to-optic couplers • Relays (coil to contact isolation) 1IEEE Std 384 defines a maximum credible voltage or current transient as voltage or current transient that may exist in circuits, as determined by test or analysis, taking into consideration the circuit location, routing, and interconnections combined with failures that the circuit may credibly experience. 2 While fiber optic cables are not specifically isolation devices, they do provide an inherent electrical isolation capability. Since the fiber does not provide a conductive path and the separation distance associated with the cable run mitigates the potential for arcing, the isolation provided by fiber optic cable should be credited. BTP 7-11-5 Draft Revision 6 – August 2015 Qualification of isolation devices should be based on a combination of design analysis and qualification testing. The analysis should demonstrate the adequacy of the design, considering the range of possible fault conditions and variability between individual units. The qualification testing should validate the results of the analysis at the extremes of fault conditions. 2. Information to Be Reviewed Information to be reviewed includes the applicant’s or licensee’s description of the: (1) device application, (2) device design, (3) test method, and (4) test results. 3. Acceptance Criteria General acceptance guidelines for application and qualification are provided in IEEE Std 603-1991, or IEEE Std 279-1971, and RG 1.75. Acceptance criteria for the descriptions of the device application, device design, test methods, and test results are as follows: Description of Device Application Isolation devices should be classified as part of the safety system and powered in accordance with criteria of IEEE Std 603-1991 or IEEE Std 279-1971 and the guidelines of RG 1.75. If nonsafety power sources interface to the isolation device, the applicant or licensee should verify that the nonsafety power is not required for the device to perform its