Intelligent overhead line monitoring

We’re installing smart technology on our overhead power lines to get customers’ power back on quicker if there’s a fault.

In a six-year, $8.75 million investment, smart devices called remote Line Fault Indicators (LFIs) are being installed on overhead power lines throughout our electricity network.

The ‘Smart Navigator 2.0’ devices clip on to the lines between power poles and are a step towards digitalising our electricity network, with the aim of speeding up fault response for our customers.

So far, more than 400 of the devices have been installed on particularly fault-prone locations throughout the network - 82 of which were installed during the past year. Another 108 sets are planned to be installed this year.

The first remote LFIs – seven sets – were installed on the Cambridge Road feeder. This is a long rural feeder with a history of poor performance.

How they work

Attached to the line near the crossarm, the device measures the power line’s current, voltage and temperature, on average, every 15 minutes. If there’s a fault on a section of line, the device will flash a light indicating the direction of the fault. They then use the 4G communications network to report back to our Network Operations Centre (NOC).

“These LFIs provide additional visibility in real time of what is happening on the network. Those in the control room can see where the fault is, so instead of sending a crew to patrol the whole feeder to find the fault, which could take several hours, we can quickly pinpoint the area of the feeder that is affected, isolate the fault, and get customers reconnected," General Manager Electricity Karen Frew says.

LFIs are a part of a wider rollout of automation technology, designed to reduce the impact of unplanned power outages on customers. It includes increasing the remote control of switching points on the network, to be able to get the power back on sooner.

The remote Line Fault Indicators currently only work through the 4G communications network, which can be patchy outside populated towns and cities.

We're awaiting the LoRaWAN (Long Range Wide Area Network) network, which will give us more communication options for more rural, isolated areas.

The data provided by the devices that can be monitored via 4G will, however, provide valuable data for our Network Development Team.

The evaluation of the data will allow us to better understand what's happening on the network and what conclusions we need to draw, for example, for further network expansion.

Above: A Line Fault Indicator, the same as those being installed on Powerco's overhead electricity lines (pictured at top on lines in the Coromandel region).