Important differences between IEC 61643-01:2024 and IEC 61643-11:2011: ---Interpretation of the new standard for surge protectors

Surge protectors (SPDs) play a vital role in low-voltage electrical systems. They protect equipment from surges caused by lightning, transient overvoltages, etc., thereby ensuring the safe and stable operation of the equipment. As technology continues to develop, the International Electrotechnical Commission (IEC) is constantly updating the standards for low-voltage surge protectors. On December 20, 2024, IEC released the IEC 61643-01:2024 standard, replacing the previous IEC 61643-11:2011 standard. So, what are the main differences between the two? This article will take a deep look at the differences between the two standards and explore the key changes in the IEC 61643-01:2024 standard and its impact.

1. Scope of application and standard version update

IEC 61643-01:2024 is the basic document of the low-voltage surge protective device series standard, applicable to all types of SPDs, including devices that protect against indirect and direct effects caused by lightning or other transient overvoltages. This standard not only clarifies the performance requirements of SPDs, but also specifies their safety requirements, test methods and ratings, and is applicable to circuits or equipment with rated voltages up to 1000V AC (RMS) or 1500V DC.

In contrast, IEC 61643-11:2011 is a standard specifically for test methods for low-voltage surge protective devices (SPDs), which has been replaced by IEC 61643-01:2024 and the upcoming IEC 61643-11 (second edition). Therefore, IEC 61643-01:2024 is not only an update of the basic standard, but also the starting point for the development of subsequent test standards.

2.IEC 61643-01:2024 has made a number of important technical updates and clarifications compared to IEC 61643-11:2011.

The specific changes include:

a) Application clarification of SPD testing

IEC 61643-01:2024 clarifies the test application requirements for complete SPDs, "protection modes" or complete "SPD components". This is crucial for evaluating the performance of equipment in actual applications.

b) Voltage protection level measurement for combined protection modes

The standard has added a new requirement for measuring the voltage protection level of the combined protection mode between the live conductor and PE. This new requirement can provide more comprehensive surge protection performance data and help design more reliable surge protection systems.

c) T1 SPD and T2 SPD follow-current load test

IEC 61643-01:2024 adds a test requirement with a follow-current additional load to T1 and T2 type SPDs to ensure that these devices can still effectively interrupt the follow-current at lower pulse current amplitudes. This test can detect the actual operating performance of the equipment in the actual power system and ensure its reliability under surge impact.

d) Improvement of short-circuit current test requirements

The new standard updates the short-circuit current test requirements and better adapts to the modern SPD internal disconnector technology. This means that the design of SPD in the future will be more adaptable to the needs of complex power environments.

e) Improvement of dielectric test requirements

IEC 61643-01:2024 improves the dielectric test requirements for the main circuit of the SPD and adds dielectric test requirements for the electrical isolation circuit. This improvement helps to improve the electrical safety of the equipment and reduce the risks of short circuits or electric shocks.

f) Clearance requirements for electrical isolation circuits

IEC 61643-01:2024 also specifies additional electrical clearance requirements for electrical isolation circuits, further improving the safety and protection capabilities of SPD equipment.

g) Additional information for SPDs in DC systems

The standard provides more detailed information and additional requirements for SPDs in DC systems to adapt to the increasing number of DC power applications in modern electrical systems.

3. Impact and Application

The release of IEC 61643-01:2024 marks the further maturity of surge protector technology. The new standard requirements not only improve the test methods of previous versions, but also provide clearer guidance for the research, development, design and application of SPD equipment. Through these technical improvements, SPD can provide more efficient and reliable surge protection in more complex power systems.

In addition, the new standard will enable manufacturers, designers and users to select and apply SPDs based on more rigorous test data and safety requirements, thereby ensuring the long-term safe and stable operation of electrical equipment.

The main difference between IEC 61643-01:2024 and IEC 61643-11:2011 is that the former, as the basis of the low-voltage surge protector series standard, stipulates a wider scope of application and specific technical requirements, while the latter mainly focuses on the test methods of SPD. IEC 61643-01:2024 has made a number of significant technical updates to SPD test methods, performance requirements, safety measures, load testing, etc., enabling it to better adapt to the application needs of modern low-voltage electrical systems. These changes and improvements not only improve the comprehensiveness and accuracy of the standard, but also provide a higher level of protection for equipment manufacturers and users.

With the continuous improvement of electrical safety requirements, the IEC 61643-01:2024 standard will surely become an important guide in the field of surge protectors, providing more scientific and effective protection to ensure the safety and stability of modern power systems.