Power Supply Update #2

28 June 2009

Being suspended more than 50 metres in the air is all in a day’s work for our crews. Take for example work last week to replace equipment on a 132kV high voltage line, 600 metres across the Elizabeth River in a special bosun’s chair fastened to the powerline.

These high voltage lines carry much of Darwin’s electricitysupply from Channel Island Power Station and are criticalto our operations.

“Utilities in every state and territory have specialised teams to conduct this sort of high voltage work and our linesmen are no different,” says Overhead Lines Maintenance
Coordinator Brett Hills.

Maintenance work included fitting spacers to help prevent powerlines clashing together in high winds and installing dampers to control excessive vibration. “We inspect these
lines every year to make sure they are in robust working order and when we need to carry out work like this we always include training so staff gain valuable skills and experience during the operation,” Brett added.

Crews also took just four days to demolish, excavate and install new switchgear on McMillans Road in Anula. The equipment had been experiencing recurring problems which restricted work to be completed at Casuarina Zone Substation. While Darwin slept, the new switchgear was brought on line without interrupting the power supply.

While time and effort is spent on trouble spots around Darwin, Power and Water employees are also focused on preventing future outages. More than 15km of powerlines from the City Zone Substation to Mindil Beach were replaced recently to secure the electricity supply for the Cullen Bay and Cox Peninsula areas. These lines run though locations including the Gardens Golf Club and have been in place for more than 30 years.

High salt levels and moisture in the area means the lines were prone to corrosion and significant investment and maintenance was required involving 20 highly trained line crews, operators and electricians working at height and on the ground.

“This is hot, heavy and complex work that trained team members must complete while hanging off a cross-arm,” said Bertram Birk, General Manager of Power Networks.

For more information : Progressing Power and Water