Once the SPS class is established, the standard provides a base USCD value (expressed in mm/kV, where the voltage is the highest phase-to-phase system voltage). Severity Level Base USCD Requirement (mm/kV) Very Light B C D E Very Heavy
Following the standard reduces the risk of insulator flashovers caused by pollution, enhancing the reliability of high-voltage transmission lines and substations.
I recently reviewed a specification for a switchyard 500m from a cement clinker cooler. The original design called for standard anti-fog insulators. By applying :
| Standard | Title | |----------|-------| | | General principles, definitions, and pollution classes | | IEC 60815-3 | DC application for ceramic/glass insulators | | IEC 60815-4 | Polymeric insulators for AC/DC | | IEC 60507 | Artificial pollution tests (salt fog) | | IEC 60513 | Fundamental design considerations for HV insulators |
based on the specific pollution levels of a site. This part of the standard specifically excludes polymer or composite insulators, which are covered in Part 3 of the 60815 series. Key Technical Concepts Site Pollution Severity (SPS): iec 60815-2 pdf
Once you open the PDF, flip immediately to these sections:
To mitigate these risks, engineers rely on the International Electrotechnical Commission (IEC) standards. Specifically, outlines the selection and dimensioning of high-voltage insulators intended for use in polluted conditions. This article provides a detailed breakdown of what the IEC 60815-2 standard covers, why the PDF manual is essential for power engineers, and how to apply its principles in the field. What is IEC 60815-2?
From Table 2 (Level d → 31–43 mm/kV). Choose 38 mm/kV as a conservative interim value.
The standard strongly emphasizes that the Pollution Severity Map (informative) is a starting point. Critical substations and lines require actual ESDD/NSDD monitoring per IEC 60507 . Once the SPS class is established, the standard
This article provides a comprehensive overview of , which specifically focuses on ceramic and glass insulators for AC systems. We will explore its core methodology, key design parameters, and why engineering teams seek out the IEC 60815-2 PDF for grid design. The Structure of the IEC 60815 Series
Based on the SPS class determined in the first step, IEC 60815-2 provides base USCD values for glass and ceramic insulators: 22.0 mm/kV SPS Class B: 27.8 mm/kV SPS Class C: 34.7 mm/kV SPS Class D: 43.3 mm/kV SPS Class E: 54.1 mm/kV 3. Profile Correction Factors
The baseline USCD assumes a standard, well-behaved insulator profile. Because real-world aerodynamics change how dust deposits on surfaces, IEC 60815-2 introduces correction factors based on geometric parameters: The vertical distance between consecutive sheds. Shed Projection ( ): The horizontal extension of the shed from the core. Creepage to Clearance Ratio ( Cfcap C sub f ): The efficiency of the profile shape.
Utilizing standardized calculations reduces the risk of over-engineering (which wastes money on oversized towers and insulators) or under-engineering (which leads to costly grid failures). How to Access the PDF Safely and Legally The original design called for standard anti-fog insulators
: Formal logic paths to navigate from raw field measurement data to a final, verified insulator design.
It replaced the older, single-part IEC 60815 (1986) standard. The updated version provides a systematic framework to estimate pollution severity and select profile shapes. It determines the minimum creepage distance required to prevent electrical tracking and flashovers. Core Methodology of the Standard
While Part 3 of the IEC 60815 series addresses polymeric (composite) insulators, Part 2 strictly governs cap-and-pin glass units, long-rod porcelain, and post porcelain insulators.
