Energy Regulations

What IEC 61439-1 & 2 Mean for Your Low-Voltage Equipment Specifications

As of November 2014, the previous IEC 60439 standard series for low-voltage equipment has been replaced by the new IEC 61439 standard series. The new series features some organizational changes, but the most significant changes have a direct impact on the work of specifiers in selecting equipment for their clients’ facilities. In this post, I’ll discuss some details of the new requirements, along with their implications for equipment specifiers.

Developers of the new IEC 61439 series sought to address a number of perceived shortfalls in the previous guidelines. Because requirements were not always clear under IEC 60439, up to 80 percent of existing assemblies worldwide are actually not in compliance with the standard. Similarly, the respective roles of equipment manufacturers and panel builders weren’t clearly defined, so responsibility for ensuring compliance was equally difficult to understand.

The updated IEC 61439-1 provides general rules for this entire standard series, and it seeks to correct the lack of clarity in three significant ways:

  • Clearly defining the respective roles and responsibilities of original manufacturer, assembly manufacturer and specifier.
  • Replacing the concepts of TTA and PTTA with verified assembly.
  • Clarifying and reinforcing tests and their requirements.

Clearly defined roles

One potential area of confusion under the previous IEC 60439 standard was a difficulty in understanding who was responsible for specific types of safety and performance verification. The new IEC 61439-1 clearly identifies the various parties involved in specifying and manufacturing equipment and assemblies, along with their responsibilities, as follows:

  • The Specifier identifies the needs and constraints for design, installation, operation and upgrading of the complete system. This party also checks that requirements have been fully integrated by the assembly manufacturer. The specifier could be the end-user or a design office.
  • The original manufacturer carries out the original design and associated verification of an assembly system. This party is responsible for the design verifications listed by IEC 61439-2, which governs switchgear and controlgear, including many electrical tests.
  • The assembly manufacturer (or “panel builder”) – who might or might not be the same as the original manufacturer – is responsible for the completed assembly. This party is responsible for “routine verifications” if the assembly is produced according to the original manufacturer’s requirements. However, any deviation from original manufacturer instructions will force a new, full design verification process.

Replacing TTA/PTTA with “verified assembly”

Confusion also resulted from IEC 60439’s dependence on the terms “type tested assemblies” and “partially type tested assemblies,” which is why IEC 61439 eliminates those terms in favor of the new “verified assemblies.” Two categories of verification are defined in the new rules, including:

  • Design verifications, which mainly equate to the previous type-tests, with limited exceptions.
  • Routine verifications, similar to the “routine” tests outlined under IEC 60439’s TTA requirements. However, the new standard splits the previous three verifications into a 10-item list.

Clarifying and reinforcing tests and their requirements

Finally, the new IEC 61439-1&2 provide clear, thorough explanations of the tests and other requirements to ensure equipment safety and operability.

Fortunately for specifiers, Schneider Electric offers a full line of equipment that is already compliant with the new standards’ requirements. And, just as important, this equipment has been tested to work together in complete assemblies. With these certifications already in hand, you can trust your installations will operate safely and reliably, in full compliance with these new guidelines.

Get more detailed information, along with details on specific Schneider equipment, by downloading our informative brochure “IEC 61439-1 & 2 Standard: The reference for safe and reliable LV switchboards” and register for our dedicated Consulting Engineer Portal to access additional tools, resources and product information.


No Responses

Leave a Reply

  • (will not be published)