IEC 61505:1998
Nuclear reactor instrumentation - Boiling water reactors (BWR) - Stability monitoring
- Standard No.
- IEC 61505:1998
- Release Date
- 1998
- Published By
- International Electrotechnical Commission (IEC)
- Status
- Latest
- IEC 61505:1998
- Scope
- This International Standard applies to boiling water reactors (BWR) designed to ensure that thermal-hydraulic oscillations are either not possible, or can be reliably and readily detected and suppressed. Compliance with the criteria can be demonstrated by: a) preventing power oscillations; b) detecting and automatically suppressing power oscillations. Monitoring of the reactor stability state, which is the object of this standard, can support a) and b) by providing information on plant stability characteristics. Monitoring will detect the approach to, and occurrence of, oscillations. The purpose of this standard is to - describe appropriate plant parameters for use in stability monitoring; - define analysis methods for relating time-varying plant information to reactor stability figures of merit, such as the decay ratio; - provide technical guidelines regarding stability monitoring functional and performance requirements. The following items are not covered by this standard: a) control system instability; b) recommendations for implementing a particular solution or a combination of solutions; c) requirements for analytical methods associated with each method; d) requirements for manual operator and automatic actions necessary to suppress power oscillations or reduce decay ratios; e) general safety significance of reactor instability. This standard also does not cover predictor type stability monitors (e.g. frequency domain models which may be used on line to calculate decay ratio for current reactor conditions).
IEC 61505:1998 history
- 1998 IEC 61505:1998 Nuclear reactor instrumentation - Boiling water reactors (BWR) - Stability monitoring
