Why Arc Fault Control and Venting is industry best practice for Bushfire Mitigation on Medium Voltage Overhead Networks
Throughout Australia, NOJA Power’s OSM Recloser is used for bushfire mitigation technology. Collaboration between the Brisbane based manufacturer and Australian utilities has culminated in a suite of protection and automation functionality deployed to resolve the challenges of Australia’s catastrophic bushfire season.
After the 2009 Victorian Bushfire Disaster, thousands of NOJA Power Reclosers have been deployed to solve and mitigate bushfire risk.
Nine years have passed, and the system is achieving its goal, according to NOJA Power.
Driven by the findings of the Royal Commission into the 2009 Victorian Bushfire disaster in Australia, NOJA Power has developed a suite of functionality to address the recommendations of the report.
The key to bushfire mitigation strategy in reclosers relies on:
- Enclosing the insulation system completely in an IP66 rated enclosure
- Secure communications and control of the auto-reclosing sequence
- Advanced sensors and protection functionality designed to monitor and act on high-impedance earth faults
- Any form of reclosing is not the solution to Wildfire or Bushfire Mitigation. Reclosers must be used in single shot mode on fire risk days.
Reclosing is an important, but small part of an overall bushfire mitigation strategy. Utilities need to consider fault detection techniques to detect high impedance faults in the first place. NOJA Power has worked diligently together with Australian utilities to provide a suite of functionality in the OSM Recloser to provide the tools necessary to detect fire-starting scenarios.
While the deployment of NOJA power reclosers throughout Australia has helped mitigate fire risks across the country, it is imperative that the entire system be considered. For all the protection functionality in the device, an absolute necessity is arc fault control and venting.
In the substation, any switchgear must consider the ramifications of the outcomes of an arc flash scenario. A 30-year life for any piece of switchgear is a good benchmark – but it is essential to consider what occurs in an arc flash event. When it comes to bushfire mitigation, development of protection functionality such as the OSM recloser’s high resolution SEF, harmonics protection, ANSI 46 BC broken conductor and admittance protection are only part of the solution – the reality is that this functionality is contained in the world’s only solid dielectric, arc fault-controlled and vented recloser. If there is a catastrophic lightning strike, surge, or physical harm to the recloser – the device will act safely and comply to the Arc Fault Test Standard.
The OSM recloser is a fully encapsulated product, where the entire device is contained within a stainless steel IP66-rated enclosure. This enclosure ensures arc fault containment and venting in accordance with the requirements of IEC62171-200 and confirmed by type test certification of the recloser at Test & Certification Australia. For a full test video, go to https://www.nojapower.com.au/typetest/recloser-arc-fault-containment-solid-dielectric.html.
Not only does this rugged enclosure provide containment and controlled venting for arc faults, it protects the solid dielectric iInsulation from the harsh Australian sun. Solid dielectric insulation reliability is achieved by shielding the insulators from solar radiation, and the NOJA Power OSM recloser provides peace of mind in this environment. With over 15 years of proven service in the worst that Australia’s climate has to offer, the OSM recloser is Australia’s number one choice in bushfire mitigation.
“Bushfire risk is one of the greatest challenges that Australian electricity utilities face,” said NOJA Power Group Managing Director Neil O’Sullivan. “At NOJA Power, we have focused significant R&D resources to equip our OSM recloser products with functionality and safety features to provide the tools to our electricity utility customers to correctly manage their bushfire mitigation programs.”