Electrical systems keep businesses running, but when faults are unnoticed, the consequences can be costly and dangerous. That is why many companies turn to electrical thermographic surveys. Using thermal imaging cameras, engineers can identify issues that are invisible to the eye, allowing action to be taken before small problems turn into major failures.
This blog explains how to conduct an electrical thermographic survey in a way that is both safe and reliable. Whether you are a facilities manager, maintenance professional, or simply want to understand how this process works, here is what you need to know.
Following some basic principles can help you complete your thermal survey.
Why Thermographic Surveys Matter
Electrical faults rarely appear out of nowhere. They build up overtime through loose connections, overloaded circuits, or worn components. In most cases, these faults generate heat long before they cause a failure. Thermal imaging makes that heat visible.
The benefits of catching problems early include:
Safety: Reducing fire and shock risks.
Cost savings: Avoiding expensive downtime and emergency repairs.
Efficiency: Extending the life of equipment and maintaining performance.
For businesses responsible for critical infrastructure, a survey is not just a precaution. It is part of responsible maintenance.
Preparation Is Key
Before any survey begins, safety comes first. Electricity can kill, and only trained experts should attempt this kind of work. Preparation makes the difference between a quick, effective inspection and one that risks both safety and accuracy.
A safe survey starts with:
Making sure the work area is well lit and clear of unnecessary hazards.
Informing colleagues about the task to avoid accidental interruptions
Confirming that the engineer has the correct training and protective equipment.
Once the environment is safe, attention can turn to the electrical systems themselves. Distribution boards and panels need to be energised and ideally under load Without current flowing, there is no heat to detect, and hidden issues may remain invisible.
Conducting the Survey
When the equipment is live and ready, the engineer begins scanning with a thermal camera. To capture useful results, several practical points are important.
Access: In many cases, removing covers from panels gives a clearer view of connections and terminations. However, this is not always possible due to time, safety or customer restrictions.
Reflections: Shiny surfaces can reflect heat sources nearby, creating misleading hot spots on the image. A trained engineer checks carefully to confirm whether the heat is genuine.
Camera settings: Accuracy depends on current input. The camera should be set to the ambient temperature, humidity, and a standard emissivity value, often 0.96%. These adjustments ensure the images match the real thermal conditions.
Colour palette: For electrical surveys, the “iron” palette is the most practical. It highlights heat variations clearly with lighter colours showing cooler spots.
Temperature range is another consideration. Most surveys are carried out between -20°C and 120°C. If components are running hotter than this, the camera’s range can be adjusted up to 650°C to capture accurate readings before returning to the standard range.
Interpreting the Results
The value of a thermographic survey lies not just in taking images, but in understanding what they show. A hot spot may point to a loose connection, an overloaded cable, or uneven load distribution. Each issue carries its own risks and requires a different response.
A professional report provides:
Clear images of the affected components
A description of the issue identified
Recommended next steps, from further investigation to immediate repair.
This documentation helps businesses plan maintenance, prioritise urgent work, and demonstrate compliance with health and safety standards.
The “iron” colour pallet is usually the best to use in this scenario.
Seeing the Problem Before It Happens
Thermal imaging often reveals issues before any visible signs appear. For example, an engineer might scan a distribution board that looks perfectly fine to the eye, only to discover one terminal running much hotter than the others. Left unchecked, that single fault could cause equipment failure or even fire.
By identifying the anomaly early, the component can be repaired or replaced in hours rather than days. The business avoids costly downtime, keeps staff safe, and ensures its electrical system continues to perform as required.
Common Questions Answered
Do the systems need to be switched off?
No, the survey requires the equipment to be energised and preferable under normal load. This is what makes the faults visible.
Is it disruptive to business operations?
In most cases, the process is quick and non-intrusive. Engineers can often complete surveys without interrupting normal operations.
How often should surveys be carried out?
This depends on the size of the businesses and the critical nature of the equipment. Annual surveys are common, but high-demand environments may require more frequent checks.
The Value of Professional Expertise
While thermal cameras are widely available, interpreting the results require knowledge and experience. Misreading images can lead to missed faults or unnecessary repairs. That is why businesses often choose professional survey providers who combine specialist training with high-quality equipment. Thermascan has been carrying out electrical thermographic surveys across industries for decades. Our engineers are trained to deliver accurate, actionable results, helping businesses protect staff, reduce costs, and keep systems running smoothly.
Electrical thermographic surveys are a crucial part of preventative maintenance that protect people, save money and keep operations efficient. With the right preparation, equipment and expertise, businesses can see issues long before they become serious problems.
If you want to learn more about arranging an electrical thermographic survey for your business, or to speak with our team about your specific needs. Visit our thermographic survey page or contact us today.