Nuclear power plants – Instrumention, control and electrical power systems – Requirements for electromagnetic compatibility testing

BS IEC 62003:2020 pdf free.Nuclear power plants – Instrumention, control and electrical power systems – Requirements for electromagnetic compatibility testing.
Nuclear instrumentation, control, and electrical equipment important to the safety of a nuclear plant (as defined in the IEC/IEEE 60780-323 standard) shall satisfy the requirements for emissions generated by the equipment and immunity to electromagnetic interference as documented in this document. Controlling the emissions from all types of equipment (important to safety and non-safety equipment) is necessary to ensure that the electromagnetic environment is bounded by the test levels recommended in this standard.
Table 1 contains a list and description of the EMC immunity and emissions tests applicable to nuclear l&C and electrical equipment important to safety to be installed into a nuclear facility. These tests address the main types of electromagnetic disturbances found in a typical nuclear power plant environment and not all types of tests may be applicable for a particular piece of equipment or installation. Adequate technical justification for the elimination of particular tests should be provided in the EMC purchase specification, test plan, and/or test report. Further guidance regarding the applicability of the various tests, test levels, and frequency ranges can be found in IEC 61000-6-5 (immunity for power station equipment) and IEC 61000-6-7 (immunity for safety-related system in industrial locations).
In the case of existing and installed equipment inside nuclear power plants, the requirements defined in this document may be aligned according to the state-of-the-art for EMC qualification testing valid during the time of installation. For such equipment, operational experience may be taken into account.
The guidance in this document was developed for l&C equipment but may also be applied to electrical equipment. However, because of the unique nature of electrical (power) equipment, some additional considerations might be required. An example of these considerations is provided in Annex H.
When the electromagnetic environment in a plant is unknown, it may become necessary to obtain emissions data at the point of the installation, using guidance in Annex 0. Guidance in Annex E can be used to determine the EMC performance of equipment already installed in a nuclear power plant facility.
6 Electromagnetic environment
The typical locations covered by this document are found within nuclear power plants and similar nuclear facilities. The locations generally follow a typical power plant installation shown in Figure 2 based on IEC 61000-6-5. In Figure 2, the solid lines do not represent physical boundaries between the areas where the equipment is installed, but indicate generic boundaries between electromagnetic environments. A majority of the l&C and electrical equipment covered under this document will be located in environments defined as interface type 2 meaning that it will not directly interface with the electrical process (medium and high voltage power distribution). For I&C and electrical equipment that does directly interface with the electrical process, the typical environment would be defined as interface type 3 in Figure 2. Therefore, the test levels specified in this document will be based upon the assumption that the equipment to be tested will be installed in these interface type 2 or interface type 3 areas of the plant.
It should be noted that the electromagnetic environment within these interface type 2 and 3 (and other) areas can vary significantly depending on the specific plant location and installation/design practices. If the equipment will be installed in a more or less severe environment (or if the country specific standards are different), then the test levels can deviate from those presented in this document as long as an appropriately documented justification is provided. Guidance is provided in Annex B to aid in determining specific test levels and providing the proper justification based upon the intended installation location. Further information on the interface types in typical power stations can be found in IEC 61000-6-5. Additional information for classification of the electromagnetic environment
can be found in IEC TR 61000-2-5.
7 Immunity testing
7.1 General
Nuclear l&C and electrical equipment important to the safety of a nuclear plant shall satisfy the requirements for immunity to electromagnetic interference documented in Table 1 of this document. If an item is deemed to be inappropriate for the EUT, exemption shall be justified by consideration of operating conditions or other relevant factors and documented in the EMC test plan. The degrees of test severity and acceptance criteria that are established for nuclear l&C and electrical equipment emissions and immunity testing shall be documented in the EMC test plan and test report.
Immunity levels for nuclear l&C and electrical equipment have been established in accordance with Table 2 through Table 5 for a typical installation in a nuclear facility. For each item of nuclear l&C and electrical equipment, if one or more of the immunity levels from Table 2 through Table 5 are determined to be inadequate (too restrictive or non-conservative) for the different disturbance types in Table 1 then the individual test level(s) can be established and properly documented in the EMC test plan based on the severity of the electromagnetic environment (using guidance from Annex B) where the system will be installed or the category of function performed by the system to be installed (based upon IEC 61226). Electromagnetic environments are classified in accordance with the qualitative parameters in informative Annex B and Annex C. Country-specific clauses may require the application of higher or lower immunity levels.
The functional quality criteria for nuclear l&C and electrical equipment belonging to safety systems (items) or systems (items) important to safety shall meet criterion A, as defined in Annex A, except if it is justified that transitory degradation of performance does not affect the safety function. The justification shall be documented in the EMC test plan. Other systems shall meet a functional quality criterion based on the application or country specific practices.
The acceptance criteria for the system performance, power and signal I/O deviations, and other characteristics shall be specified in the EMC test plan. The acceptance criteria should take into account the intended application of the equipment and its potential impact on nuclear power plant safety.
7.2 Applicability
The application of tests for evaluation of immunity depends on the particular equipment, its configuration, its ports, its technology and its operating conditions.
The immunity test requirements for equipment intended for use in nuclear power plants reflect the situation given in Figure 2 for interface type 2 and interface type 3 and are provided in Table 2 through Table 5. Tests shall be applied to the relevant ports of equipment according to Table 2 through Table 5. Tests shall only be carried out where the relevant ports exist.
Exemptions for any of the particular immunity tests (it applicable) are noted within the tables. It may be determined from consideration of the electrical characteristics and usage of a particular equipment that some of the tests are inappropriate and, therefore, unnecessary. In such a case, it is required that the decision and justification not to test shall be documented in the EMC test plan and test report. Further information regarding test exemptions can be found in Annex C based upon the electromagnetic environment characteristics described in Annex B.
7.3 Measurement uncertainty
The guidance for the assessment of the instrumentation uncertainty of an immunity or emissions test is specified in IEC TR 61000-1-6 or in the corresponding basic standard and should be considered.BS IEC 62003 pdf download.
Nuclear power plants – Instrumention, control and electrical power systems – Requirements for electromagnetic compatibility testing