Partial Discharge (PD) monitoring system

A partial discharge monitoring system for high voltage and medium voltage assets.


Detect and monitor partial discharge using fiberoptics

OptiFender is an innovative fiber optic sensing solution which enables partial discharge monitoring of high voltage assets in challenging environments.
Thanks to its unique fiberoptic technology and passive sensing principle, the OptiFender system delivers a set of benefits for your most challenging installations:

Immune to electro magnetic interference
Monitoring of remote assets (> 40km)
Galvanically isolated sensors for easy installation
Completely passive – no power at sensing location required
Critical monitoring for HV & MV assets

OptiFender allows you to localize PD source in an asset remotely and in real time

HV Cable Accessories

For retrofitted and embedded cable accessories, each joint location is monitored with a pre-assembled sensor set.

Switch gear

Detect partial discharge in switch gear


Diagnose and monitor transformers to identify and localize PD source

HV/MV inverter fed machines

Detect partial discharge in electrical machines in real time

What is OptiFender

OptiFender: The World’s first fiber optic based partial discharge monitoring system

OptiFender is the world’s first fiber optic partial discharge monitoring system.

Its unique patented technology delivers a highly reliable fiber optic solution, while keeping the same performance as state-of-the-art electrical systems.

OptiFender includes:

  • Modular acquisition unit
  • Passive fiber optic PD sensors
  • Magnetic clamps and installation accessories
  • Dedicated software package
How does it work

Passive Fiber Optic PD Sensor for Accurate Monitoring

OptiFender measures the acoustic emission signals of partial discharges and tracks their evolution over time with fiber optic PD sensors. The measuring principle behind the fiber optic PD sensor is based on the acoustic emission technology.
The small and completely passive sensors can be easily installed on any kind of asset, enabling the detection of close-by internal and surface partial discharges.
The acoustic emission signals acquired by the sensor is transmitted to the acquisition unit through a standard telecommunication optical fiber. The acquired data is then displayed and analyzed through the dedicated software.

How does it compare to an electric system

Measuring internal Partial Discharge At PDIV and PDEV

Our revolutionising technology allows us to detect even the slightest indications of PD. Our success is not only demonstrated through the work we do with our clients but through our peer-reviewed research as well.

What OptiFender offers

EMI immunity

  • Completely passive transducer
  • Crystal clear signal in any environment
  • Consistent measurements and reliable data

Remote locations

  • Acquisition unit and sensors can be spaced tens of kilometres apart
  • Monitoring of remote HV assets
  • Simple cabling to cover long distances

Easy installation

  • Uninterrupted equipment operations during installation
  • Safe, galvanically-isolated sensor
  • No technically complex training needed
  • Small and lightweight sensor

No power required

  • No pre-amplifiers needed
  • Fiber optic sensors do not require any electrical power


OptiFender data acquisition unit

The data acquisition unit is a modular readout that transmits and receives the optical signal from the sensor.

OptiFender sensors and accessories

These components detect parameters and ensure optimal sensor connectivity, crucial for transmitting optical signals.

OptiFender data interpretation​

Our software analyzes the signals from the sensors, converting them into meaningful insights.

“OptiFender allowed us to solve the main limitations and now we are able to benefit from long-distance coverage and EMI immunity. After trying out of the first OptiFender system, we were happy about the results and proceeded to use OptiFender for a number of current projects,”

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