Thermal Scanning Electrical

Thermal Scanning Electrical

Thermal Scanning is the use of a thermal imager to detect heat energy, which can then be converted into a visible image (for more detail see What Is Thermal Scanning).  One of the major applications for thermal imaging is to verify the health of electrical systems, leading to early detection of faults, even before the human eye can see them.  

Why can thermal scanning be used on electrical systems?

Thermal scanning can be utilised on any electrical system as it creates heat energy as a waste byproduct, or sometimes even as the main purpose such as a heater! Both heat and electrical energy are measured in the same way; joules of energy or watts if we account for time.  The amount of energy is directly proportional to the amount of voltage and current being used.

Thus, when we examine a 20 Amp fuse operating at more than 20 Amps of current with a thermal camera, we can see the elevated temperature when compared to other similar components.  In this case the amount of current was verified by attaching a clamp meter and measured at 30 amps; indicating that either the fuse needs to be resized or the load rebalanced to ensure an optimal electrical configuration.

What benefits are there of getting thermal scanning completed on my electrical infrastructure?

As mentioned, thermal scanning is able to pick up issues before they become apparent to the naked eye.  Some of these benefits include:

• Minimising the risk of fire and damage due to failure of components,
  • Which ensures peace of mind for you as the owner.
• Reduce cost of repairs by only replacing faulty components,
  • When the location of a fault is known the component can be replaced or repaired quickly without having to replace multiple items!
• Scheduling in shutdowns so they can be completed with other works,
  • As we find faults early, this allows problems to be fixed with other routine maintenance.
• Preventing unexpected loss of power,
  • When components fail they can either do so by catching fire, exploding or just failing.  Some of these are worse than others, but all will result in the loss of power potentially costing millions of dollars in down time.
• Identify overloaded circuits or under rated cables, and
  • When cables and fuses aren’t rated properly the chances of failure increase, however thermal scanning can detect these problems quickly and efficiently.
• Ensuring longevity of components through balanced loads.
  • Unbalanced loads are one of the more common problems in electrical,  where the phases haven’t been balanced causing excessive heat generation through specific components.

Thermal imaging can detect a range of different problems with electrical infrastructure which can range from the obvious overheating components to something as simple as loose and poorly terminated connections.  Some of the major ones we encounter on a daily base include:

• Loose terminations,
• Underrated cables,
• Rust and degradation,
• Unbalanced loads, and
• Malfunctioning equipment.

To help put into perspective how bad some of these faults can be even before failure, we have provided an image of one of the worst thermal faults we have ever found with a peak temperature above 500°C!

Even in the above photo (without feeling the heat), it would be extremely difficult to detect this fault without the use of thermal imaging, even though this component is about to fail and potentially catch fire!