Rapid Earth Fault Current Limiter

Powercor is installing leading-edge technology across our electricity network as part of a Victorian Government program to reduce the likelihood of powerline-related bushfires.

Known as Rapid Earth Fault Current Limiters (REFCLs), the technology works like a large safety switch on our electricity network, reducing the risk of fires starting from powerline faults.

Between 2017 and 2023, we’re installing REFCLs in 22 of our electricity zone substations across Western Victoria’s highest bushfire risk areas in three Tranches.

Tranche 1 of the program was completed in 2019.

See tranche map.

Over the first summer REFCLs have been in service (2018-2019), there were actual examples of the technology working successfully to prevent the risk of fire starts.

To complete installation of the REFCLs safely, it is possible some customers may experience a small number of planned outages. Our team works with the community, business and stakeholders to determine the best time for these planned outages, and we provide information about them via post beforehand.

If you have an enquiry about outages in your area, please call our Customer Contact Centre on 13 24 12.

How does a REFCL work?


What is Rapid Earth Fault Current Limiter (REFCL)

A Rapid Earth Fault Current Limiter (REFCL) is technology that rapidly reduces the power in 22kV, multi-wire powerlines when it detects phase-to-earth faults on the electricity network.

The technology works like a large safety switch and reduces the likelihood of a fire starting if a powerline comes in contact with the ground or a tree limb.

How does a REFCL work?

When a powerline comes into contact with the ground or a tree, the energy released can cause a large spark. The line can continue sparking if it remains live, increasing the potential for a fire.

What happens on Total Fire Ban days?

While the safety devices are effective all year round, on days of Total Fire Ban they will operate at heightened fault sensitivity, in line with regulatory requirements.

When they operate, crews patrol the line to determine the cause of the fault and ensure it is safe for the community before switching power back on.

How do you test that a REFCL is ready for use?

There are four stages of testing that the network is REFCL ready.

  1. Stress testing
    Here we test that our network is adequately hardened for the higher REFCL voltages. This testing takes place overnight to ensure the least impact to customers.
  2. REFCL in service
    Once stress testing is complete, the REFCL can be placed into service. Over a few weeks we review the technology to make sure it is working as designed.
  3. Primary fault testing
    During this stage we create faults on the network to ensure the REFCL meets the required performance criteria. This testing is carried out at various locations across the local area. Customers may see minor interruptions to their supply during this stage.
  4. ESV compliance
    The final stage of testing is to demonstrate to the safety regulator, Energy Safe Victoria (ESV), that the REFCL meets the legislated performance criteria. Here we repeatedly create faults on the network to test the REFCL’s performance. Afterwards we prepare a report and submit it to ESV, which reviews the report and issues a letter of compliance. After this the REFCL will be operated as legislated with specific controls utilised on days of Total Fire Ban.
Why are you installing REFCLs?

In 2016 the Victorian Government mandated the introduction of REFCLs at 22 of Powercor’s zone substations as part of its Bushfire Safety Program.

The program is aimed at reducing the risk of powerline-related bushfires in Victoria’s highest bushfire risk areas and forms one of the Government’s responses to the 2009 Victorian Bushfires Royal Commission.  We support the initiative in the interests of community safety.

Where are you installing REFCLs?

Powercor will install REFCLs at 22 zone substations across regional Victoria. The program has been divided into three tranches. Exact dates may be subject to change. See tranche map above for further details.

How were the locations chosen?

REFCL locations were chosen by the Powerline Bushfire Safety Program (PBSP) based on the risk and consequence of a bushfire starting. The locations listed are all considered as high risk for bushfires.

What impacts will the work have?

To complete installation of the REFCLs safely, it is possible some customers may experience a small number of planned outages.

Our team works with the community, business and stakeholders to determine the best time for these planned outages, and we provide information about them via post beforehand.

Why am I impacted by REFCL work when I live in the centre of town?

The REFCL technology monitors powerlines up to 40km away from a zone substation. The entire network in this area must be compatible with the REFCL technology, meaning we need to make improvements to the network in town, on the outskirts of town and beyond.

How can I prepare for planned outages?

We try to minimise all outage durations but here are some tips to prepare:

  • Look after your health – have a contingency plan ready if you rely on life support equipment or need electrical items to care for babies, the disabled, elderly or pets. Keep warm with extra layers or blankets.
  • Pre-heat your home – If you have an electric heating system, then heat your home or just the rooms you are using to a
    comfortable temperature before the planned outage is due to begin. Then prevent heat loss by draught-proofing doors and windows and keeping them shut. Close curtains at night to keep the heat in.
  • Charge mobile phones, laptop computers and portable backup batteries – Charge up the day before so you can still communicate with friends and family, get updates aboutwhen power will be restored or reach emergency services when needed.
  • Keep connected using a hotspot – Your modem won’t work without power but you can still access the internet, school or work files via
    data connection on your mobile phone. Check with your telecommunications provider about bonus data allowances available during COVID-19 restrictions.
  • Keep food safe – Make sure your refrigerator is set to 5 degrees or below to ensure food stays as fresh as possible. An unopened refrigerator will keep food cold for about four hours. An unopened, full freezer will retain
    its temperature well enough to preserve food for two days. For more information, visit the Australian Institute of Food Safety: https://www.foodsafety.com.au/blog/food-safety-during-power-outages
  • Download some entertainment -If you can, download your favourite movies or television shows to a portable device soyou don’t miss out during an outage.
  • Back up computer files – Make sure important computer-based records for your home, study or work are backed up and if necessary, saved on an external hard-drive or storage device before the planned outage begins.
  • Have alternative energy available – If you use alternative energy sources for powering water pumps and equipment or cooking (like
    diesel generators or BBQs), then make sure they are fuelled and operational. Be safe – outdoor equipment should not be used inside your home. Have battery powered lamps or torches on hand and make sure you know how to open garage doors and gates manually if they don’t have a battery back-up.
  • Stay up to date – You can keep track of power outages and receive reminders about planned works.

    Register for SMS or email messages to keep track of outages at:

    Our Outages app available for smartphones and tables also provides up to date information including the estimated time for power to be turned back on.

Have a question for our team?

Have a question for our team?