60815-2 Pdf — Iec

IEC 60815-2: Selection and use of surge arresters - Part 2: Selection and use of surge arresters for HV power systems

IEC 60815-2 is a standard published by the International Electrotechnical Commission (IEC) that provides guidelines for the selection and use of surge arresters for high-voltage (HV) power systems. The standard is part of the IEC 60815 series, which deals with the selection and use of surge arresters.

Scope

The scope of IEC 60815-2 is to provide recommendations for the selection and use of surge arresters for HV power systems, including:

• Surge arresters for protection of HV power transmission and distribution systems
• Surge arresters for protection of HV power substations and switchgear

Key aspects of the standard

The standard covers the following key aspects:

1. Classification of surge arresters: The standard defines the types of surge arresters, including:
   • Gapless surge arresters (e.g., metal-oxide surge arresters)
   • Gapped surge arresters (e.g., silicon carbide surge arresters)
2. Selection criteria: The standard provides guidelines for selecting the right surge arrester for a specific application, including:
   • System voltage
   • Maximum continuous operating voltage (MCOV)
   • Short-circuit current
   • Protection level required
3. Performance requirements: The standard specifies the performance requirements for surge arresters, including:
   • Energy handling capability
   • Response to steep-fronted waves
   • Response to slow-fronted waves
4. Testing and validation: The standard outlines the testing and validation procedures for surge arresters, including:
   • Type tests
   • Routine tests
   • Special tests

Benefits of using IEC 60815-2

The use of IEC 60815-2 provides several benefits, including:

1. Improved protection of HV power systems: By selecting and using surge arresters that meet the requirements of the standard, HV power systems can be better protected against overvoltages and surge events.
2. Increased reliability: The standard helps ensure that surge arresters are designed and tested to perform reliably in various operating conditions.
3. Enhanced safety: The standard promotes the safe selection and use of surge arresters, reducing the risk of injury or damage to people and equipment.

Who should use IEC 60815-2?

IEC 60815-2 is relevant to a wide range of stakeholders, including:

1. Power utilities: Transmission and distribution system operators, as well as power generation companies.
2. Electrical engineers: Design engineers, application engineers, and system planners involved in the design and operation of HV power systems.
3. Surge arrester manufacturers: Manufacturers of surge arresters for HV power systems.

By following the guidelines and recommendations outlined in IEC 60815-2, users can ensure that surge arresters are selected and used effectively to protect HV power systems against overvoltages and surge events.

IEC/TS 60815-2 is a Technical Specification titled "Selection and dimensioning of high-voltage insulators intended for use in polluted conditions – Part 2: Ceramic and glass insulators for a.c. systems"

. It provides specific guidance for choosing and sizing ceramic (porcelain) and glass insulators used in outdoor high-voltage AC systems exposed to environmental contamination. Core Content and Scope iec 60815-2 pdf

The document builds upon the general principles established in IEC/TS 60815-1

(which defines pollution classes) to offer practical engineering guidelines for specific material types. iTeh Standards Insulator Types : Specifically covers materials for AC systems. Design Focus : Helps engineers determine relevant dimensions, such as creepage distance

, and select appropriate profiles (e.g., standard vs. "fog type") based on the site's pollution severity. Key Sections

: Typically includes scope, normative references, pollution severity levels, the relation between pollution and specific creepage distance, and profile characterization parameters. Appendices

: Often contains practical tools like a questionnaire for evaluating polluted areas and information on maintenance practices like greasing and washing. Relationship to Other Parts

The IEC 60815 series is divided by material and system type: IEC/TS 60815-2 - PLSLine IEC 60815-2: Selection and use of surge arresters

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6. Selection Procedure (Step-by-Step from Standard)

1. Determine SPS class via ESDD/DD measurements or using the descriptive table (Annex A of standard).
2. Select base USCD from SPS class table.
3. Apply correction factors for insulator shape, diameter, and voltage.
4. Calculate minimum required creepage distance:
   Creepage (mm) = USCD × (V_line-line / √3)
5. Select insulator model meeting or exceeding this value.
6. Verify with test (e.g., fog chamber test per IEC 60507 if required).

Common Misconceptions About IEC 60815-2

7. Comparison with Older Standards

| Feature | IEC 60815 (1986) | IEC 60815-2 (2008) | |---------|------------------|---------------------| | Pollution classes | 4 (Light to Very Heavy) | 4, but refined ESDD ranges | | USCD guidance | Fixed values (e.g., 25 mm/kV for heavy) | Ranges with correction factors | | Voltage correction | No | Yes | | Shape correction | No | Yes (K₁) | | DC guidance | No | Separate part (60815-3) |

Example 1: 220 kV line in coastal area (Medium pollution)

• SPS = Medium (b)
• Base USCD = 22 mm/kV
• Required creepage = 22 × (220 / √3) ≈ 22 × 127 = 2,794 mm
• Use anti-fog profile: K₁ = 0.9 → effective USCD = 24.4 mm/kV → creepage = 3,099 mm

3. Selection of Insulators Based on Pollution Severity

This is the core of the standard. The IEC 60815-2 PDF provides a systematic method to:

• Determine the site pollution severity (SPS). This is done using:

  • Long-term field measurements (leakage current, ESDD – Equivalent Salt Deposit Density, or NSDD – Non-Soluble Deposit Density).
  • Qualitative observation of the environment (proximity to sea, desert, factories, farms).
  • Reference to a map of known pollution zones.

• Classify the pollution level into one of five classes:

  • a – Light: No industries, low population density.
  • b – Medium: Industrial zones not producing heavy conductive deposits, agricultural areas.
  • c – Heavy: High industrial activity, dense traffic, coastal areas up to 10 km.
  • d – Very Heavy: Heavy industrial plumes, high desert dust, direct sea spray.
  • e – Extreme: Special cases, e.g., active volcanic ash, industrial fallout within 500m.

7. Conclusion

IEC 60815-2 provides a robust, scientific framework for ensuring the reliability of ceramic and glass insulators in polluted environments. By moving beyond simple "mm/kV" rules and introducing correction factors for diameter and profile, it allows engineers to optimize insulator strings—avoiding both under-design (flashovers) and over-design (unnecessary cost and weight).

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Recommendation: If you need the official document for contractual or certification purposes, you should purchase the PDF directly from the IEC Webstore (iec.ch) or through authorized distributors like Techstreet or the IEEE. Surge arresters for protection of HV power transmission