BS/EN 61000-1-2-2016 pdf download.Electromagnetic compatibility (EMC) Part 1-2: General — Methodology for the achievement of functional safety of electrkal and electronic systems including equipment with regard to electromagnetic phenomena.
All persons, departments and sub-contractors responsible for carrying out safety-related activities for performance with respect to electromagnetic phenomena should be identified. Their responsibilities shall be fully and clearly communicated to them. Where appropriate other persons, departments and organizations, which could influence the safety-related performance achieved by the system, shall be made aware of these responsibilities.
The individuals who have responsibility for one or more of the activities within the scope of this document, shall, in respect of those activities for which they have responsibility, specify all management and technical activities that are necessary to ensure the achievement and demonstration of functional safety performance with respect to electromagnetic phenomena of the safety-related systems. This includes the selected measures, techniques and tests used to meet the requirements of this document.
As part of the functional safety management activities, procedures shall be specified for ensuring that all persons involved in any activity within the scope of this document have the appropriate training, technical knowledge, experience and qualifications, accredited as necessary, relevant to the specific duties that they have to perform. These procedures shall define what information is to be communicated between interfaces, and what form the communication shall take. In addition, the procedures shall document how cases of reported electromagnetic disturbances on the safety-related system are analysed for their relevance to the systems or activities for which the organisation is responsible, and that recommendations are made to minimise the probability of a recurrence, Procedures shall be specified for ensuring prompt follow-up and satisfactory resolution of relevant recommendations relating to safety-related systems, including those arising from verification, validation and incident reporting and analysis.
Organizations shall maintain a system to initiate changes as a result of defects relevant to electromagnetic phenomena being detected in safety-related systems or equipment for which they are responsible and, if they are unable to make the changes themselves, to inform users of the need for modification in the event of the defect affecting safety.
NOTE Moe informahon on management of functional safely is given n IEC 61508-1.
5.5.3 Management of functional safety performance with respect to electromagnetic phenomena at element supplier level
In general, a safety-related system is a combination of a number of elements integrated together to provide one or more safety functions, and possibly additional non-safety-related functions. The functional and performance requirements of individual elements may be specified and designed as a bespoken product or procured as a commercial off the shelf product. Suppliers providing products or services to an organization having overall responsibility for one or more activities within the scope of this document shall deliver products or services as specified by that organization.
Many publications include basic descriptions of electromagnetic environments considering the electromagnetic phenomena and disturbance levels typically expected in such environments. General information about the description and the levels of electromagnetic disturbances in various locations can be found in the standards or technical reports of the IEC 61000-2 series. Examples of descriptions of various environments are given in IEC 61000-2-5. These descriptions, however, are given in terms of compatibility levels.
IEC 6 1000-4-1 gives applicability assistance and provides general recommendations concerning the choice of relevant tests described in the IEC 61000-4 series. It is noted that standards designed for the achievement of EMC, which are based primarily on technical/economic factors, may not adequately describe the electromagnetic environment for the achievement of functional safety for safety-related systems.
Table A.1 provides an example for the selection of electromagnetic phenomena to be considered when specifying requirements. Since the electromagnetic environment does not vary with respect to the SIL of systems placed in an installation, most severe electromagnetic environments shall be considered for all electromagnetic functional safety situations.
The most severe electromagnetic environment in which the safety-related system is to be installed shall be determined (e.g. by means of measurements, assessments, etc.) by either designers, manufacturers, installers or users of the safety-related system. All types of the electromagnetic phenomena (see Table 2) shall be considered The information from IEC 61000-2-5 summarized in Table A.1 Is presented as a guide but does not cover the higher disturbance levels that can occur at some locations. Once the most severe electromagnetic environment is known, the safety-related system designer shall choose only equipment specified by the equipment manufacturer for use In an electromagnetic environment equal to or more severe than the maximum environment. Equipment manufacturers typically specify that their equipment has been tested to applicable EMC standards and comply with them at specified levels. If the known application environment exceeds the equipment specifications, appropriate means shall be applied to ensure adequate performance. Such means could include shielding enclosures or other techniques as detailed in Annex B.
The levels of electromagnetic disturbances indicated in various EMC standards, reports or technical specifications shall be considered very cautiously with regard to their application for functional safety. In particular, consideration shall be given to the following:
a) The electromagnetic disturbance levels vary according to a statistical distribution (see Figure E.1), and the levels shown as examples in Table A,1 can be exceeded in some particular circumstances However, such circumstances may only exist infrequently or at particular sites. It is important to establish the levels of these disturbances for functional safety purposes.
b) The standardised immunity test methods, test levels and performance criteria found in the immunity test standards are related to operational requirements and not to functional safety. BS/EN 61000-1-2-2016 pdf download.