Intermediate Advice Regarding Publishing of AS/NZS4777.1:2024 and Implementation of NS194
On 23 August 2024, Standards Australia published AS/NZS4777.1:2024
Ausgrid Engineering teams are currently reviewing Ausgrid Standard NS194 which refers the previous version of AS/NZS4777.1, but also has additional requirements for embedded generation.
Whilst a more complete review of NS194 is ongoing, Ausgrid is providing the following engineering advice to embedded generation customers, designers and installers regarding the following topics which have been attracting many recent enquiries:
Single Phase Maximum Inverter Capacity
NS194 Clause -5.3.1 – In accordance with Appendix C2 of AS/NZS4777.1:2024 Appendix, Ausgrid will allow up to 30kVA of total Inverter Capacity (including AC-coupled battery inverters) to be connected to a single phase supply point provided that the premise electrical installation is appropriately rated (e.g. switchboard rating, cabling) and the export to the grid is limited to no more than 10kVA (note this is above the 5kVA specified in AS/NZS4777.1:2024). A design must be provided showing how the export limiting will be configured.
Impacts to Aggregate >30kVA to 200kVA Inverter Energy Systems Connected to a Network Supply Point
NS194 Clause 5.4.1 – In accordance with AS/NZS4777.1:2024 Ausgrid will adopt the increase to aggregate IES capacity on a single network supply point that does not require interface protection (previously known as Central protection) from >30kVA to 200kVA. Ausgrid will still need to complete a network capacity assessment for any network supply point that has, or will, have a total IES capacity of more than 30kVA connected, even if an export limit is proposed. Please note that AS/NZS4777.1:2024 still requires some installations type >30kW to have interface protection (such as inverter power sharing devices). Ausgrid will be revising the application fee accordingly for these connection types in the coming weeks.
Inverter Energy Systems >200kW (Total)
NS194 Annexure C – Ausgrid will require the use of interface protection settings as per AS/NZS4777.1:2024 Table 3.1 in lieu of Annexure C of NS194. There are currently no other immediate changes to the connection process for >200kW IES installations, however further changes will be considered as part of the update to NS194.