Arctic Utility finds difficult earth faults with Safegrid’s solution


Arctic Utility finds difficult earth faults with Safegrid’s solution

Tunturiverkko is the northernmost electricity grid company in Finland with over 2000 kilometers of grid length. It operates in over 7% of Finland’s land area in the Arctic conditions of Northern Lapland.

The business wanted to accurately locate short circuits and earth faults in the 20kV distribution grid for quick fault isolation action and location of the fault origin.


In May 2024, a permanent fault occurred in Tunturiverkko’s distribution grid due to the failure of an insulator in a pole transformer at the end of a grid branch. The broken insulator allowed a phase conductor going to the transformer to hang freely against the pole, causing multiple earth faults. Moreover, the wooden pole burnt at the contact point with the phase conductor. 

Safegrid reported the incident as multiple earth fault alarms, indicating the location to the start of the branch. Given the longstanding collaboration between Safegrid and Tunturiverkko, the fault data provided by Safegrid was used immediately by Tunturiverkko. Based on the reported fault locations, the affected grid area was quickly isolated using remote-switches, and the technicians were dispatched to the nearest manual switch to remove the faulty branch from the grid. The quick fault isolation reduced any trial-and-error fault sectionalizing attempts. 

Moreover, the field patrol’s fault search time was reduced about an hour from the average.

With Safegrid’s solution, the customer was able to:

  • Accurately locate earth faults.
  • 40% of patrol team’s time was saved.

“Safegrid has helped us accurately locate earth faults, allowing us to find fault locations quickly and shorten outage times.”

Heija Länsman,
Service Manager


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