9 March – Update on Central Highlands reliability work

Powercor crews have made further progress on identifying the cause of multiple power outages that have been occurring in the Macedon Ranges and Central Highlands during the past fortnight.

Crews are today focusing on a 400 metre stretch of powerlines along Martin Street South in Blackwood which was identified overnight as the location of a fault on the network.  This follows work conducted over the past 10 days which narrowed down the issue on the more than 260 kilometre line to a 20 kilometre section.

Crews this week installed fault indicators on this 20 kilometre section and last night deactivated a network safety switch allowed us to detect a more precise location for investigation.  A momentary power outage at 10.52pm last night has narrowed down the potential fault location.

While we are still yet to identify the exact cause of the outages, we are significantly closer to locating and fixing the issue.

Residents will today see Powercor crews from Kyneton, Ballarat and Ardeer inspecting and replacing electrical equipment such as insulators, transformers, high-voltage leads and lightning surge arrestors on seven high-voltage poles in Blackwood.

To allow them to safely conduct this work, we will need to turn off power to a small number of customers in the area. We are contacting these customers directly about this work.

Since early last week, a dedicated team of engineers and field crews have been conducting manual and thermal inspections along more than 260 kilometres of powerlines.

Our attempts to locate the fault site have been complicated by the use of a safety switch called a Rapid Earth Fault Current Limiter (REFCL) on the main powerline into this area.

While the REFCL is activating as designed to prevent bushfires from being caused by electrical assets, it cuts off the power extremely quickly, making it difficult to find the fault as there is typically no visible damage to the network.

Last night’s mild weather conditions allowed us to safely and temporarily turn off the REFCL protecting this area.  This helped us to better identify and record the fault when it occurred.

The installation of REFCLs in high bushfire risk areas like the Macedon ranges was mandated by the State Government as recommended by the 2009 Victorian Bushfire Royal Commission.

In addition to today’s work, we are continuing to use various technologies to conduct further inspections of the powerline to identify any issues that may cause future outages.

We are doing everything to address the reliability issues being experienced by customers in this area.

In the long term, the reliability of our networks is supported by an extensive, annual program of asset inspection, maintenance and augmentation as well as vegetation management.

Increasingly, how we plan and design our networks to be reliable well into the future is being influenced by the need to be resilient to hotter summers, more erratic weather conditions and longer bushfire seasons which are now more common in our environment.

We will be continuing to update customers as we make further progress on this work.

Customers can also call us on 13 22 06.