NB/T 20060-2012 in English

1 Scope

This standard specifies the separation requirements to be met for nuclear power plant instrumentation and control (I&C) systems and their cables important to safety.
This standard is applicable to nuclear power plant I&C systems, and their cables, that are important to safety. It is also applicable to temporary installations which are part of those I&C systems important to safety (for example, auxiliary equipment for commissioning tests and experiments).
This standard applies to the I&C of new nuclear power plants as well as to I&C upgrading or back-fitting of existing plants. For existing nuclear power plants, only a subset of the requirements is applicable; this subset is to be identified at the beginning of any project.


2 Normative References

The following documents are indispensable for the application of this document. For dated references, only the dated editions apply. For undated references, the latest editions (including any amendments) apply.
GB/T 13630 Design for Control Rooms of Nuclear Power Plants (GB/T 13630-1992, IEC 60964:1989, eqv)
GB/T 15474 Classification on Instrumentation and Control Function Important to Safety for Nuclear Power Plants (GB/T 15474-2010, IEC 61226:2005, MOD)
IEC 60332 (all parts) Tests on E1ectric Cab1es Under Fire Conditions
IEC 61000 (all parts) E1ectromagnetic Compatibi1ity — Part 6-5: Generic Standards — Immunity for Power Station and Substation Environments
IEC 62096 Nuc1ear Power P1ants — Instrumentation and Contro1 — Guidance for the Decision on Modernization

3 Terms and Definitions

For the purposes of this document, the following definitions apply.
3.1
Associated circuit
Circuit of a lower safety category that is not physically separated or is not electrically isolated from the circuit(s) of the higher category by acceptable separation distances, safety class structures, barriers, or electrical isolation devices but meets suitable criteria for safety.
3.2
Barrier

Foreword I
1 Scope
2 Normative References
3 Terms and Definitions
4 General Principles for Separation Within I&C Systems Important to Safety
5 Design Basis
6 Requirements for Cabling Separation
Appendix A (Informative) Structural Changes of This Standard Compared with IEC 60709:2004