IEC TS 60815-2:2025

IEC TS 60815-2:2025, which is a technical specification, is applicable for the selection of ceramic and glass insulators for AC systems, and the determination of their relevant dimensions, to be used in high-voltage systems with respect to pollution. This document applies to insulators for outdoor installation only.
This document gives specific guidelines and principles to arrive at an informed judgement on the probable behaviour of a given insulator in certain pollution environments.
The basis for the structure and approach of this document is fully explained in IEC TS 60815­-1.
The objective of this document is to give the user means to:
- determine the reference unified specific creepage distance (RUSCD) from site pollution severity (SPS) value or class;
- evaluate the suitability of different insulator profiles;
- determine the necessary USCD by applying corrections for insulator shape, size, position, etc. to the RUSCD;
- if required, determine the appropriate test methods and parameters to verify the performance of the selected insulators.
This second edition of IEC TS 60815-2, together with IEC TS 60815-1, cancels and replaces the first edition of IEC TS 60815-2 published in 2008. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) Some terms and definitions are modified or introduced in this document, such as USCD, nominal creepage distance, RUSCD, creepage factor, insulator trunk, etc.;
b) From RUSCD of reference insulator to USCD of candidate insulator, the correction factors are introduced and revised, such as altitude correction, diameter correction, shed profile correction and parallel insulator number correction;
c) Profile suitability on ceramic and glass insulators was simplified.