The standard applies to instrument transformers designed for systems with a nominal voltage higher than . It covers units that produce either analogue or digital secondary signals for use with measuring instruments, control systems, and protective devices.
As Part 1, it must be read in conjunction with specific product standards, such as IEC 61869-2 for current transformers and IEC 61869-3 for inductive voltage transformers. Key Technical Requirements Iec 61869-1 Pdf
It primarily addresses rated frequencies from 15 Hz to 400 Hz , as well as DC applications. The standard applies to instrument transformers designed for