The AS/NZS 4777.1 standard has long been a cornerstone in ensuring the safe and effective installation of inverter energy systems. With the release of the 2024 version, significant updates have been made to simplify the installation process, enhance clarity, and accommodate the evolving landscape of renewable energy. Whether you’re an installer, engineer, or stakeholder in the solar industry, these changes are essential to understand for compliance and effective system design.
1. Streamlining Terminology: Removal of “Standalone Mode”
The 2024 revision starts with a clean-up of the language, including the removal of the “standalone mode” definition. Previously, this term described systems operating independently of the grid. Its elimination is part of a broader effort to reduce confusion and make the standard more accessible.
2. Clarifying Related Standards
One of the most beneficial updates is the clearer distinction between AS/NZS 4777.1 and other relevant standards, particularly AS/NZS 5033 and AS/NZS 5139. This revision ensures that AS/NZS 4777.1 now solely governs the installation of inverter energy systems, while AS/NZS 5033 covers PV arrays up to the inverter input terminals, and AS/NZS 5139 focuses on battery systems. This separation reduces the risk of overlapping regulations and simplifies the compliance process.
3. Introduction of Phase Balance Limits
For those involved in larger installations, the new phase balance limits are particularly noteworthy. The standard now imposes a maximum limit of 30 kVA for single-phase installations, contingent on the grid supply capacity or the installation’s overcurrent protection. This update is crucial for commercial and industrial projects, where higher capacities are common.
4. Revised Protection Requirements: From “Central” to “Interface”
The transition from “central protection” to “interface protection” marks another significant change. Systems under 200 kVA no longer require interface protection unless mandated by the local distribution network service provider (DNSP). This update could simplify installations, though compliance with DNSP requirements remains key.
5. Limiting Inverter Main Switches
To enhance safety and maintenance, the 2024 standard limits the number of inverter main switches to a maximum of two on any switchboard with loads. For installations with more than two inverters, an aggregation or marshalling board must be used, ensuring a single switch can control all inverters. This change simplifies both operation and maintenance.
6. New Category: Inverter Power Sharing Devices (IPSD)
As shared solar resources become more prevalent in multi-dwelling developments, the introduction of “inverter power sharing devices” (IPSD) addresses this growing trend. This new definition is critical for scenarios where multiple users, such as residents in an apartment block, share a single PV system.
7. Embracing Vehicle-to-Grid (V2G) Technology
The 2024 version also paves the way for the integration of vehicle-to-grid (V2G) technology. With provisions for both AC and DC connections, electric vehicles can now be more seamlessly integrated into the energy system, allowing them to either draw power from or contribute to the grid.
8. Updated Supply Type Definitions
To further reduce confusion, the standard has updated the definitions of supply types:
- Normal Supply: Traditional grid supply controlled by the main switch.
- Supplementary Supply: Systems that work alongside the grid but don’t function independently.
- Alternative Supply: Systems that switch to a backup source, like a generator, during grid outages.
- Independent Supply: Systems that power an installation independently, using the grid only as a charging source.
- Substitute Supply: A niche category where a system supplies power to a single outlet, similar to solutions like the Fronius PV Point.
9. Consistency Across Standards
Lastly, the terminology and definitions have been aligned with AS/NZS 4777.2 to ensure consistency. This is crucial for manufacturers and installers who work within these frameworks, as it simplifies the design and installation process across different standards.
Conclusion: Navigating the Future of Inverter Energy Systems
The 2024 AS/NZS 4777.1 standard represents a significant step forward in the regulation of inverter energy systems. By clarifying language, introducing new categories like IPSD and V2G, and ensuring consistency across related standards, these changes aim to simplify the compliance process and accommodate the increasing integration of renewable energy. Understanding these updates is essential for anyone involved in the design, installation, or regulation of solar and battery systems in both residential and commercial settings.
At StaySafe Industry Training, we’re committed to keeping you informed and equipped with the latest knowledge to navigate these changes. Our courses are designed to help you stay ahead of industry standards, ensuring that your skills remain relevant and your installations meet the highest levels of safety and efficiency.
