January 2026: New Standard Enhances Telecom Surge Protection in Electrical Engineering

In January 2026, the landscape of electrical engineering standards sees a significant evolution with the release of EN IEC 61643-21:2026. This pivotal update focuses on surge protective devices (SPDs) for telecommunications and signaling networks—addressing the increasing risks of lightning and transient overvoltages in today’s connected, power-over-Ethernet world. As systems grow more complex and data-driven, ensuring robust surge protection is essential for reliability, safety, and regulatory compliance. This article provides a deep dive into the single, yet transformative, standard introduced this period.

Overview / Introduction

The electrical engineering sector depends heavily on standardization to ensure the safe and reliable functioning of increasingly intricate networking and power systems. As networks converge—carrying both data and power—exposure to electrical surges grows, heightening the risk of equipment failure and service disruption.

Surge protective devices (SPDs) are crucial for mitigating these risks, especially within telecommunications and signaling networks operating up to 1,000 V RMS and 1,500 V DC. This 2026 update, EN IEC 61643-21:2026, not only supersedes its previous editions but also establishes a new global benchmark for design, installation, and maintenance of SPDs.

What Will You Learn?

• The scope and critical requirements of the new EN IEC 61643-21:2026 standard
• Key compliance and safety implications for organizations
• Best practices and practical steps for implementation
• Technical testing and documentation considerations for SPDs

Detailed Standards Coverage

EN IEC 61643-21:2026 – Surge Protective Devices for Telecommunications and Signaling Networks

Low voltage surge protective devices – Part 21: Surge protective devices connected to telecommunications and signalling networks – Requirements and test methods

Scope and Applicability

Published in January 2026 by CLC, EN IEC 61643-21:2026 applies to SPDs designed to protect telecommunications and signaling networks and associated equipment from both direct and indirect effects of lightning or other transient overvoltages. This includes systems carrying up to 1,000 V RMS or 1,500 V DC, and networks where power may coexist with data—such as Power over Ethernet (PoE) scenarios.

The standard’s scope covers:

• SPDs with at least one voltage-limiting component (clamping or switching)
• Systems where protection is needed against surges on lines carrying data and/or power
• Performance and safety criteria, and comprehensive testing requirements

Key Requirements and Specifications

This second edition is a technical revision that replaces previous editions and amendments. Major updates include:

• New structure aligned with IEC 61643-01:2024, unifying requirements across the surge protection family
• Expanded and updated safety requirements, including more rigorous criteria for overstress and disconnectors
• Clear classification and definitions of SPD configurations (from two-port to multi-port, including common and differential modes of protection)
• Enhanced marking and manufacturer documentation requirements, ensuring traceability and clarity for installation and maintenance
• Expanded electrical, mechanical, and environmental requirements—covering protection levels, insulation, dielectric withstand, and aging
• Stringent testing procedures for impulse durability, AC durability, and blind-spot performance
• Integration with international telecom standards (e.g., ITU-T K-series for specific network components)

Who Needs to Comply?

• Network equipment and device manufacturers
• Telecom operators and infrastructure providers
• Electrical engineering firms specializing in critical communications
• System integrators for industrial control and signaling networks
• Facilities managers of environments reliant on reliable telecommunications

Practical Implications for Implementation

Key action points and considerations for adopting the standard include:

• Risk assessment of all networked and PoE-enabled infrastructure for surge vulnerability
• Selection and documentation of compliant SPD types per network topology
• Type and routine testing of protective devices as specified, including impulse tests, insulation measurements, and environmental robustness
• Marking and record-keeping for traceability and field maintenance
• Staff training to recognize updated SPD configurations and status indicators

Notable Changes from Previous Editions

• Structural overhaul to harmonize with IEC 61643-01
• Addition of specific safety requirements for overstress, disconnectors, and fault modes
• Stronger emphasis on product information, transmission characteristics, and installation documentation

Key highlights:

• New structure and terminology harmonized with latest IEC standards
• Expanded testing and marking requirements for traceability
• Stronger focus on safety in overstress and short-circuit scenarios

Access the full standard:View EN IEC 61643-21:2026 on iTeh Standards

Industry Impact & Compliance

How Does EN IEC 61643-21:2026 Affect Businesses?

This new standard marks a critical step forward for equipment and system safety in telecommunications infrastructure. By clarifying requirements for protection, testing, marking, and documentation, it:

• Raises the bar for equipment suppliers, ensuring that only rigorously tested SPDs reach the market
• Provides telecom operators with objective performance benchmarks for surge protection solutions
• Triggers compliance obligations for new installations, upgrades, and sometimes even for major maintenance in regulated sectors
• Helps reduce downtime and protect investment in digital infrastructure from catastrophic failure

Compliance Considerations & Timelines

Organizations involved in telecommunication network design, deployment, or maintenance should:

1. Audit existing infrastructure for SPD compliance
2. Establish transition plans for incorporating the updated standard in procurement and engineering specs
3. Implement staff training on new safety, marking, and maintenance requirements
4. Engage with certified testing and certification bodies for documentation and certification within required timelines

While the document is directly applicable from its publication date, practical transition periods may be coordinated with local regulators or industry bodies.

Benefits of Early Adoption

• Minimized risk of compliance failure and associated penalties
• Enhanced protection against both transient and sustained overvoltages
• Improved system reliability and reputation

Risks of Non-Compliance

• Increased exposure to equipment damage and downtime
• Potential regulatory action or penalties
• Reduced access to public-sector or infrastructure contracts

Technical Insights

Common Technical Requirements

While EN IEC 61643-21:2026 covers a wide range of conditions and network types, several core technical requirements and procedures recur across all device categories:

• Impulse durability and voltage protection level: SPDs must withstand specified impulse currents without altering protective characteristics
• Type Testing: Devices are subjected to a battery of electrical, mechanical, and environmental tests, including simulated lightning impulses, overvoltage events, and temperature extremes
• Marking and Product Information: Clear, durable markings must be affixed to each SPD, and comprehensive installation documentation must be supplied
• Transmission Performance: For data-carrying links, tests for insertion loss, return loss, longitudinal balance, and crosstalk can be mandatory depending on the declared use case

Implementation Best Practices

• Integrate SPD selection and installation with early-stage network and facility design
• Regularly review product standards and manufacturer certifications for updates
• Maintain thorough documentation for every installed SPD, including test records and marking details
• Schedule routine system testing—especially surge/impulse tests in environments prone to electrical storms or where network uptime is mission-critical

Testing and Certification

Testing includes:

• Impulse and current-limiting response time
• Dielectric withstand (immunity to high voltages)
• Overstress and fault mode performance
• Mechanical strength and environmental resistance (heat, moisture)

Certification pathways:

• Leverage iTeh Standards to access up-to-date information on accredited test labs and certification requirements for global markets.

Conclusion / Next Steps

The arrival of EN IEC 61643-21:2026 ushers in a new era for surge protection in telecommunications and signaling networks. By enforcing more robust, harmonized requirements, it supports a safer, more reliable future for digital and power networking infrastructures.

Key Takeaways:

• Early adoption reduces risk, enhances system reliability, and streamlines regulatory compliance
• Close attention to marking, documentation, and testing details is essential
• Ongoing staff education and regular audits are critical for ongoing compliance

Recommendations:

• Audit your existing telecommunication and signaling networks for compliance gaps
• Develop an implementation and training roadmap for your teams
• Work proactively with suppliers and test labs to procure and verify compliant SPDs

Stay ahead of evolving regulatory requirements, and ensure your networks are protected against increasingly frequent and severe electrical disturbances.

Discover the full text and detailed requirements:View EN IEC 61643-21:2026 on iTeh Standards

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