SMB - STANDARDIZATION MANAGEMENT BOARD

IEC Guide 115:2021 presents a practical approach to the application of uncertainty of measurement to conformity assessment activities in the electrotechnical sector. It is specifically conceived for use in IECEE Schemes as well as by testing laboratories engaged in testing electrical products to national safety standards. It describes the application of uncertainty of measurement principles and provides guidance on making uncertainty of measurement calculations. It also gives some examples relating to uncertainty of measurement calculations for product conformity assessment testing. IEC Guide 115 has been prepared by the IECEE Committee of Testing Laboratories (CTL) to provide guidance on the practical application of the measurement uncertainty requirements of ISO/IEC 17025 to the electrical safety testing conducted within the IECEE CB Scheme. The IECEE CB Scheme is a multilateral, international agreement, among over 40 countries and some 60 national certification bodies, for the acceptance of test reports on electrical products tested to IEC standards.The aim of the CTL is, among other tasks, to define a common understanding of the test methodology with regard to the IEC standards as well as to ensure and continually improve the repeatability and reproducibility of test results among the member laboratories. The practical approach to measurement uncertainty outlined in this document has been adopted for use in the IECEE Schemes, and is also extensively used around the world by testing laboratories engaged in testing electrical products to national safety standards.

IEC GUIDE 108:2019 defines rules for dealing with horizontal functions and horizontal publications. This Guide is to be used in conjunction with the ISO/IEC Directives and with the aspect­ specific Guides.
The fundamental concept of a horizontal publication is that it is an international publication (not a TS or a PAS) that is widely applicable and to be used by all relevant committees and that has undergone an enhanced approval process as described in this document.
In this Guide:
- the term "committees" includes technical committees, project committees, subcommittees and systems committees.
- the term "publication" includes International Standard, Technical Report, Technical Specification, Publicly Available Specification and Guide.
- the term "product" is used to refer to individual products, processes, services and combinations thereof, commonly known as "systems".

This Guide provides strategic principles, derived from market experience, for use by IEC and ISO technical committees and subcommittees working in the industrial automation sector, as well as other bodies within IEC and ISO with interests in the work of these committees.

IEC Guide 108:2006 is mandatory, it defines and establishes the relationship between horizontal standards and product publications. Specifies procedures for the designation of horizontal standards and for their use.

Horizontal publication giving guidance for the harmonization of product and system standards within substations where the highest voltage for equipment is higher than 1 kV. Contains recommendations for common specifications for all HV substation product standards, each of which is augmented by the technical background specific to each TC, which naturally retains freedom in its technical choices. For use by TCs involved in high-voltage (HV) substation systems, such as TCs 13, 14, 17, 20, 22, 28, 32, 33, 36, 37, 38, 57, 95 and 99.

The purpose of this guide is to find a way to overcome the lack of consistency and unnecessary discrepancies between standards within one system. Furthermore, the cost of over-standardization of one component when the nearest linked component is under-standardized must be considered. The supplementary cost does not in any way increase the reliability of the system as a whole. Since the same external stresses (climatic, electrical, mechanical) apply to all the components of the substations, the consistency of their technical features is vital. Hence, standards will deal more and more with the same essential requirements for safety, environmental impact, end of life, availability and integration of systems. All product standards for a single system have to fulfil these requirements with the same degree of responsibility. The aim of this guide is to provide common rules for HV substation equipment.