From professionals – to professionals. Our goal is to enhance and improve our portfolio to meet customer needs and market potential.

Over the years, Nortroll has established a very strong brand. Our three recognised product lines are listed to the right.


Fault Passage Indicators to locate short circuit and earth faults.


Fault current indicators for the underground medium voltage distribution network (6-36kV).


A modular system with different building-blocks allowing the utilities to tailor-make a system.


Norwegian coming soon...


LineTroll R400D

Fault Passage Indicator for overhead lines (6-132kv) with built in GSM communication Module.

LineTroll R400D Fault Indicator indicates earth- and short-circuit faults and can distinguish between permanent and transient faults. The indicator has two sensors and use both the electrical field and the magnetical field to detect faults on all three phases.

A high intensity red strobe-flash LED indicates permanent faults and with the adjustable lens, the indication can be seen from long distance both in day– and night-time. Transient faults and low battery warning are indicated by separate LED's.

LineTroll R400D has a built in GSM modem which will send SMS and/or GPRS to one or more recipients upon a fault situation and is one important part in NORTROLL's system for Smarter Network Management.

LineTroll R400D continuously monitors the line voltage and current, and detects faults either when the current exceeds an absolute configurable threshold or variation in current within a specific time (di/dt). The units has a built-in load current compensator which allows for detection of very low phase-to-earth faults. The unit has inrush current filtering to avoid false indication when line is energized.

The unit is fully self-contained, no external transformers or connections is required and can be mounted in all types of poles and line configurations.


  • Highly visible local indication
  • Indicates both transient and permanent faults (Configurable)
  • Detects phase-to-phase and low phase-to-earth faults
  • Low power -> long battery lifetime
  • Two-way communication
  • Automatic reset feature
  • Easy configuration without any DIP-switch settings
  • Remotely configurable (Wireless or GSM)
  • Time-stamped alarms and event log
  • Built-in GPS for positioning and time-synchronization (option)


We offer professional help in setting up a system that will help you reach your goals in a cost efficient way.


We have distributors in over 40 countries. Click the map for contact information.

Design & development: CATCH