Are You Detecting Partial Discharge or Just Catching It Too Late?

It starts small, tiny insulation defects, weak points, ageing materials. Over time, it builds. And if it goes unnoticed, it can lead to serious transformer failure.

The problem is, many utilities still rely on periodic testing or temporary monitoring, which means PD is often only detected after it has already progressed.

Why PD monitoring is changing

Traditionally, PD has been something you check occasionally during maintenance, commissioning, or when you suspect a problem.

But networks are changing:

• Assets are ageing
• Loads are increasing
• Failure consequences are higher

So, waiting for the next test window is no longer enough.

The shift across the industry is clear: from one-off diagnostics to continuous monitoring.

Where traditional approaches fall short

Many products in the market do a good job in short-term testing or fault investigation. But in everyday operation, utilities often struggle with:

• No continuous visibility
  You only see PD when you go looking for it
• High noise environments
  Substations are noisy, making reliable detection difficult
• Limited integration
  Data sits outside normal operational systems

So even when PD is measured, it’s not always usable or actionable.

What utilities need

Today, the priority is simple:

• Detect PD early
• Track how it changes over time
• Integrate it into everyday asset management

In other words, don’t just detect PD, understand it as it develops.

A more practical way to monitor PD

This is where Insulect’s Qualitrol PD monitoring systems take a different approach.

Instead of temporary setups, they’re designed for permanent, always-on monitoring of transformers.

Using UHF-based detection, they provide:

• Reliable PD detection even in high-interference environments
• Continuous trending, not just snapshots
• Clear alarms based on real behaviour, not just isolated events
  

Why that matters in real operations

With continuous monitoring, you can:

• See PD activity as it starts, not after it grows
• Track trends over time and understand severity
• Act earlier, with more confidence

And because the system integrates with standard protocols, PD data becomes part of your normal control and asset management workflow, not a separate exercise.

Built for real utility environments

Many traditional products are either too focused on testing or too complex to deploy at scale.

Qualitrol, supported locally by Insulect, is built around what utilities need:

• Permanent installation on critical transformers
• Strong performance in noisy substations
• Seamless integration into SCADA systems
• Local engineering support throughout the lifecycle

The bigger picture

PD isn’t just a defect; it’s a progressive warning sign. Catching it early can mean the difference between planned maintenance and unexpected failure, but that only happens if you’re watching continuously rather than occasionally.

Relying on snapshots simply isn’t enough for something that evolves gradually and can escalate without obvious warning. When it comes to partial discharge, visibility is everything.

Want to improve visibility of PD across your transformer fleet?

Talk to Insulect about Qualitrol PD monitoring and how it can support a more proactive, continuous approach to asset management.