IPD has summarised all the vital information that you need to know.

AS/NZS 61439 was first introduced in 2016 and over the past six years, industry experts have continued to work through and adapted the standards to ensure Low voltage Switchgear and Controlgear assemblies are compliant and held to the highest standards. IPD has provided you with the important information that you need to know about AS/NSZ 61439.

AS/NZS 61439 is the new series of standards made up of 8 parts covering Low-voltage Switchgear & Controlgear assemblies, superseding the AS/NZS 3439 standards that have been in place since 2002. Compliance of the latest standards is a legal requirement for all new and replacements assemblies, effective of May 2021.

The standards were created to ensure that the overall construction, performance and suitability of devices and components is held to the highest standard.  By doing so, reduces risk and increases the safety of the distribution boards in residential, commercial, and industrial applications.

The eight parts of AS/NZS 61439 consist of the following:

• Guide to specifying assemblies
• General rules
• Power Switchgear and Controlgear assemblies
• Distribution boards to be operated by ordinary persons (DBO)
• Particular requirements for assemblies for construction sites (ACS)
• Assemblies for power distribution in public networks
• Busbar trunking systems (busways)
• Assemblies for specific applications

What are the main reasons for the change from AS/NZS 3439 to AS/NZS 61439?

The main reason for the introduction of AS/NZS 61439 was to provide a solution to the inconsistencies that were in AS/NZS 3439. The five key areas in AS/NZS 3439 that were addressed in the AS/NZS 61439 standards are:

1. The requirements for proving the design of a Partially Type Tested Assembly (PTTA) are very subjective with no clear guidelines. The standard relies on the knowledge and integrity of the assembler.
2. While manufacturers had to assign a rating to each circuit, but not required by the standard to prove its rating. In the new standard the rating of a circuit in an installed assembly needs to be verified and proven.
3. With the limitless permutations and combinations that are possible with assemblies it is impractical to test each and every variant design.
4. Lack of tests to prove the constructional requirements.
5. Who is responsible for the switchboard is not clearly defined.

What has been implemented in the new AS/NZS 61439 standards?

The AS/NZS 61439 standards has addressed the concerns from the superseded AS/NZS 3439 standards and has included an adoption of the IEC 61439 standards, with modifications made to suit the specific requirements for Australia and New Zealand.

Outlined below are the top 8 changes that have been included:

1. The concept of Type Tested Assemblies (TTA) and Partially Type Tested Assemblies (PTTA) has been replaced with design verification.
2. Seven type tests of the superseded standard have been replaced by 13 design verifications that cover constructional and performance requirements. The 13 design verification provide three options with limits and conditions.
3. Responsibilities between the Original Manufacturer and the Assembly Manufacture have been clearly defined.
4. New tests to cover Constructional Requirements have been added:
   • Resistance to corrosion test
   • Resistance to abnormal heat and fire due to internal electric effects
   • Lifting test
   • Mechanical impact test
   • Marking test
5. Conditions and limits imposed on device substitution.
6. Power frequencies withstand voltage tests and impulse withstand voltage tests are mandatory requirements.
7. Verification of the Forms of Internal Separation is a mandatory requirement.
8. AS/NZS 61439.3 is specific for distribution boards that are intended to be operated by ordinary persons (DBOs). Rated current of a DBO should not exceed 250A and rated current of any outgoing circuit should not exceed 125A.  A number of other additional requirements detailed in AS/NZS 61439.3

What is the impact of these standards?

AS/NZS 61439 will have no major impact commercially or on contractors. It predominantly affects the testing protocols and design for switchboard manufactures, as outlined throughout the article. These changes will assist in clarifying any legal, safety and financial responsibilities that way arise during the manufacturer process of the switchboard.

At IPD we have ensured that all our Low-voltage Switchgear and Controlgear assemblies comply with the new AS/NZ 61439 standards. For any questions you need answer about the AS/NZS 61439 standards or to order a Low-voltage Switchgear or Controlgear assembly contact your local IPD team member.