As the renewable energy landscape continues to evolve, the 2024 revision of AS/NZS 4777.1:2024, Grid connection of energy systems via inverters—Installation requirements, marks a significant step forward in the safe and efficient installation of inverter energy systems. This updated standard, which replaces the 2016 edition, introduces several key changes aimed at simplifying installation processes, enhancing clarity, and accommodating new technologies like Vehicle-to-Grid (V2G) systems.
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Refining terminology and scope

The 2024 revision introduces streamlined terminology, including the removal of the term "standalone mode," to help improve clarity accessibility. AS/NZS 4777.1:2024 now clearly distinguishes its scope from related standards such as AS/NZS 5033:2021, Installation and safety requirements for photovoltaic (PV) arrays, which covers PV arrays up to the inverter input terminals, and AS/NZS 5139:2019, Electrical installations—Safety of battery systems for use with power conversion equipment, focusing on battery systems. This separation aims to reduce the risk of overlapping regulations and simplify the compliance process.
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New limits and protection requirements

For larger installations, the introduction of phase balance limits is a critical update. The standard now sets a limit of 30 kVA for single-phase installations, depending on grid supply capacity or the installation’s overcurrent protection, which is especially relevant for commercial and industrial projects.
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Additionally, there has been a significant revision in protection requirements. The transition from "central protection" to "interface protection" means that systems under 200 kVA no longer require interface protection unless specified by the local Distribution Network Service Provider (DNSP). This change could simplify installations but requires careful attention to DNSP requirements.
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Enhancing safety and embracing new technology

To help improve safety and maintenance, AS/NZS 4777.1:2024 now limits the number of inverter main switches to two on any switchboard with loads. For installations with more than two inverters, an aggregation or marshalling board must be used, allowing a single switch to control all inverters.
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Recognising the growing trend of shared solar resources in multi-dwelling developments, the 2024 revision introduces the concept of Inverter Power Sharing Devices (IPSD). This addition is for scenarios where multiple users share a single PV system.
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The standard also paves the way for the integration of Vehicle-to-Grid (V2G) technology, with provisions for both AC and DC connections. The aim of this update is to allow electric vehicles to be more seamlessly integrated into the energy system, enabling them to either draw power from or contribute to the grid.
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Simplifying definitions and consistency

To aid clarity, AS/NZS 4777.1:2024 has refined the definitions of supply types, including Normal Supply, Supplementary Supply, Alternative Supply, Independent Supply, and Substitute Supply. These updates look to enhance understanding and aim for consistency across related standards.
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Finally, the revised AS/NZS 4777.1:2024 aligns its terminology and definitions with AS/NZS 4777.2:2020, Grid connection of energy systems via inverters—Inverter requirements, with the intention of simplifying the design and installation process for manufacturers and installers working within these frameworks.
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Navigating the future of inverter energy systems

The 2024 revision of AS/NZS 4777.1:2024 reflects Australia's commitment to advancing renewable energy practices. By introducing new categories like IPSD and V2G, refining language, and aiming for consistency with related standards, these changes look to simplify adherance to the standard and support the integration of emerging technologies.
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George Sfinas, Engagement Manager at Standards Australia, stated, "These updates to AS/NZS 4777.1:2024 are essential for keeping pace with the rapid advancements in renewable energy. By clarifying standards and accommodating new technologies, our goal is to help Australia remain at the forefront of safe and efficient energy system installations."
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AS/NZS 4777.1:2024 is available via the Standards Australia Store and our distribution partners.

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