Case Study Electrical – Industrial sites

During a recent annual routine electrical thermal scan of a major industrial worksite, Thermal Scanners helped to locate and identify multiple major faults within the existing electrical infrastructure.  Some of these included excessive temperature located on Isolators, Circuit Breakers, Overload / Contactor setup and relays.  Thermal Scanners’ completes scanning of this site yearly, and due to the high level of power demands and usage, different components experience problems every year.  The previous year six faults were identified whereas during this year of scanning 13 faults were found.

High level fault on 250 Amp Isolator identified during Thermal Scanning

One of the major faults found on site was on an overloader / contactor setup which controls the fans for a crucial cooling stack.  If this cooling stack had broken, it would have caused a complete site shutdown while the fault was found, identified and rectified.  Further as the fault was at such a high range, the potential for an electrical fire was very real, which could have caused millions of dollars in damage.

High level fault on a overloader / contactor setup found during Thermal Scanning

The temperature of the above overloader / contactor setup was causing excessive temperature in both of the adjacent components, which will reduce their lifespan and cause additional costs for maintenance and replacement.  Pictured below is the contactor which shows the inside of the component beginning to burn and melt the casing.

Inside of the contactor identified in the thermal scan above

Thermal Scanners were still on site after replacement of the component, as such we completed another scan on the affected electrical board. It was found that the problem had been resolved and the adjacent components were running at normal operating temperature. Due to the company utilising thermal scanning they were able to replace a faulty component that was going to experience imminent failure before causing a site wide shutdown.

Case Study Electrical Hottest Fault

Thermal Scanners conduct hundreds of thermal scans per year at locations all around Australia. As such we are used to seeing faults regularly that surprise our clients. Sometimes the faults we find on site even shock us. This is because the faults can reach extreme temperatures that show failure is imminent.

Below we will show some of the highest temperature faults that we have found on a variety of sites, ranging from body corporates, private organisations and public buildings.

Fuse Holder above 100°C

Most often when we find thermal exceptions they appear on the terminations that connect to the cables.  However this fault extends to the actual component, in this case a fuse.  The fuse pictured below is designed to operate up to 80°C when there are no other fuses directly next to it.

Thermal fault on a fuse.

In this case the fuse is actually the hottest part and is operating well beyond its operating temperature, which potentially could have been life threatening as it has not tripped indicating there could be a problem in the circuit.  A visual image of this fault is shown below which shows the physical burns and damage to the fuse holder.

Even with the fuse burnt and damaged the circuit above is still live, active and complete!

Contactor above 200°C

In our work Thermal Scanners has found that sometimes cables have been physically burnt or damaged and yet at the time of scanning there is no load and hence no excessive temperature.  In the follow photo this is not the case and the component is still under load and has burns far beyond the typical:

Thermal fault on contactor

The above thermal image shows a maximum temperature in excess of 200°C and this is conservative due to our emissivity settings.  It can be seen that the cable is also above 100°C for a considerable length beyond the termination. Even the adjacent cable is affected by this heat!  To better show the effect of this increased heat we have also included a visual photo.

Visual photo of burns to cable

As can be seen the fault has actually caused the insulation on the cable to melt, exposing live electrical wires. Further it has begun to melt and damage the components outer casing.  If this fault was not detected an electrical fire may have resulted as soon as the next couple of days.

Circuit Breaker Above 500°C

In 2020 we completed Thermal Imaging on a customers commercial premise and during completion of the service we found a thermal exception on the wire and termination of a 3 phase circuit breaker. 

Thermal fault over 500°C on circuit breaker

Keep in mind that most circuit breakers have an operating temperature of up to 85°C including these ones manufactured by Heinemann.  With a maximum temperature in excess of 500°C this circuit breaker is operating at almost 6x its maximum recommended temperature and will almost certainly cause an electrical fire!

We hope that seeing some of these faults helps individuals and companies understand why annual thermal imaging is required on switch boards.  If any of the above faults were not detected these could have easily caused large scale loss of power and even caused an electrical fire in the immediate future with serious ramifications.