is the latest international standard that defines general requirements for instrument transformers intended for high-voltage applications . As a "Product Family" standard, it serves as the foundational document that must be used alongside specific product standards (like Part 2 for current transformers or Part 3 for inductive voltage transformers) to ensure equipment safety and reliability. Scope and Application
Its primary function is to serve as the "umbrella" document for the entire IEC 61869 series. While subsequent parts of the series deal with specific technologies (like inductive CTs, capacitor VTs, or electronic transformers), Part 1 establishes the baseline definitions, general requirements, and test methodologies that apply to all instrument transformers.
The that defines the general requirements for newly manufactured instrument transformers. Developed by the International Electrotechnical Commission (IEC), it establishes a unified framework for safety, accuracy, testing, and performance. It applies across high-voltage power generation, transmission, and distribution systems.
When buying the PDF, consider purchasing the "Redline version." This version highlights exactly what changed between the older editions and the current version, saving hours of cross-referencing. Conclusion
: It ensures strict dielectric and thermal performance to prevent equipment failure in high-voltage environments. Iec 61869-1 Pdf
Historically, instrument transformers were governed by separate standards, namely IEC 60044-1 for current transformers and IEC 60044-2 for inductive voltage transformers. The IEC 61869 series replaced the old IEC 60044 family to create a unified, modernized framework.
Mechanical stress limits that the equipment must withstand. Rated Insulation Levels
IEC 61869-1 applies to newly manufactured instrument transformers intended for use with electrical measuring instruments, protection relays, and similar devices in 50/60 Hz AC power systems (typically rated up to 800 kV and above). It covers:
Are you focusing on or voltage transformers (VTs) ? What is the highest voltage level ( Umcap U sub m ) of your system? is the latest international standard that defines general
Standard ranges are typically defined for indoor and outdoor installations, with specific ambient temperature classes (e.g., -5°C, -25°C, or -40°C).
Additional requirements for current transformers (CTs).
): The maximum r.m.s. current the transformer can withstand for a specified duration (usually 1 or 3 seconds) without damage. Dynamic current ( Idyncap I sub d y n end-sub
Guidelines regarding insulation coordination, earthing, and fail-safe designs to protect personnel and equipment. IEC 61869-1 vs. IEC 60044 While subsequent parts of the series deal with
If there is a conflict between Part 1 and a specific part (like Part 2), the specific part takes precedence. However, Part 1 fills in the gaps for any general requirement not explicitly overridden.
The document outlines strict environmental parameters under which instrument transformers must operate safely and maintain accuracy classes. These include ambient air temperature boundaries, altitude limitations (typically up to 1000 meters without correction factors), and atmospheric pollution levels. Ratings and Electrical Performance
: Organizations like ANSI (USA) or BSI (UK) also sell the adopted versions of this standard. Standards Council of Canada technical specification
Older standards treated instrument transformers purely as analog, copper-wound copper devices. IEC 61869-1 explicitly paves the way for modern smart grids by establishing definitions that accommodate and optical sensors.