THERMAL
Thermal imaging cameras are a unique tool to determine when and where maintenance is needed, for electrical and mechanical installations tend to get hot before they fail. By discovering these hot-spots with a thermal imaging camera, preventive action can be taken. This can avoid costly production breakdowns or even worse, fire.
What is infrared?
Our eyes are detectors that are designed to detect electromagnetic radiation in the visible light spectrum. All other forms of electromagnetic radiation, such as infrared, are invisible to the human eye.
The existence of infrared was discovered in 1800 by astronomer Sir Frederick William Herschel. Curious to the thermal difference between different light colours, he directed sunlight through a glass prism to create a spectrum and then measured the temperature of each colour. He found that the temperatures of the colors increased from the violet to the red part of the spectrum.
After noticing this pattern Herschel decided to measure the temperature just beyond the red portion of the spectrum in a region where no sunlight was visible. To his surprise, he found that this region had the highest temperature of all.
Why use thermal imaging?
Producing faster, better, more efficiently and at a lower cost. In order to reach these goals, industrial plants need to be running continuously: 24 hours a day, 365 days a year.
No costly breakdowns, no waste of time.
So, when you are in charge of plant predictive maintenance you really have a lot of responsibility on your shoulders.
If you could only see when components are about to fail, you could accurately decide the best time to take corrective action. Unfortunately the worst problems remain hidden until it is too late.
Thermal imaging cameras are the perfect tool for predicting failures because they make the invisible visible. On a thermal image problems seem to jump right out at you.
To keep plants operational at all times many industries have combined their predictive maintenance programs with the most valuable diagnostic tools for industrial applications on the market: thermal imaging cameras.
Whether you are monitoring high voltage equipment, low voltage cabinets, motors, pumps, high temperature equipment, looking for insulation losses… A thermal imaging camera is the one tool that really lets you SEE it all.
Electrical systems
Thermal imaging cameras are commonly used for inspections of electrical systems and components in all sizes and shapes.
The multitude of possible applications for thermal imaging cameras within the range of electrical systems can be divided into two categories: high voltage and low voltage installations.
Examples of failures in high-voltage installations that can be detected with thermal imaging:
• Oxidation of high voltage switches
• Overheated connections
• Incorrectly secured connections
• Insulator defects
Examples of failures in low voltage equipment that can be detected with thermal imaging:
• High resistance connections
• Corroded connections
• Internal fuse damage
• Internal circuit breaker faults
• Poor connections and internal damage
THERMAL DRONE APPLICATIONS FOR SOLAR PV PLANTS
Solar require ongoing maintenance and inspections over the life of a panel. As the size and number of these systems continue to increase, the time and labor required to inspect a system is increasing and becoming cost-prohibitive. Aerial inspections via drone provide an economical alternative, adding a thermal camera to the drone enables more data to be collected and at a more granular level.
Thermal drone inspections of solar photo voltaic (PV) panels are a valuable tool at every stage of a panels life.
WARRANTY INSPECTION
Many different parties involved in the development and construction of a solar provide warranties. Developers on Engineering, Procurement, Construction (EPC) teams, and component manufacturers are just a few of the parties with a warranty on a system. If a PV system is not meeting the expected production numbers there will eventually be a warranty claim that
will require an inspection. A thermal drone inspection at this time can be a more cost-effective way to gather some of the data required for a warranty claim and/or evaluation of a warranty claim.
PREVENTATIVE MAINTENANCE (PM) ANNUAL INSPECTION
Solar panels require ongoing management and maintenance. Numerous variables can impact the long-term financials of a PV system, including environmental, installation quality, and upkeep. For solar to meet its production and financial projection goals, ongoing maintenance is required as well as regular inspections to identify anomalies affecting production. Historically these inspections have been done on foot, by hand. Thermal drone inspections reduces time and labor requirements to generate the same data on the health of the system. Drones also produce more data that enables field teams to identify/classify/and localize anomalies that historically have gone unnoticed but add up to a lot of affected production and lost revenue.
It’s extremely important to understand the reason for the use of this technology and what type of information/data is required by the end user. Each type of inspection has different financial implications for different stakeholders, but all of them benefit from high-quality aerial thermography.
When solar panels loose efficiency, how does that happen?
Potential Induced Degradation (PID) is a relatively recently discovered phenomenon which can occur in solar panels although a concise understanding of what causes it is still being finalised. Tests by the German Fraunhofer Institute showed that solar panels which are susceptible can lose more than 30% of their rated power through this effect and as much as 90% in extreme cases. What is known is that sodium enrichment occurs between the chemicals used on the surface of the solar cell and the glass in certain circumstances, causing a leakage of current between the cells and the solar panel frame. The intensity of the degradation depends on the module type, the ambient environmental conditions and the position of the solar panel in the array string. A high system voltage (eg 600V +) and high ambient humidity can lead to a film of moisture on the solar panel surface. A drift of positive ions occurs from the glass towards the solar cell in the opposite direction, which is believed to cause degradation in the solar cell.
Ageging Effects
Discolouration of the EVA encapsulant Delamination of the encapsulant Oxidization
High conductivity paths (shunts) Humidity ingress
Hot spots/ hot areas
Cracks, tears in the back sealing Bubbles
Corrosion in bus bars and contacts
IR Thermography
Temperature distribution on cells and modules
Front and back of the module
Hot spots/ hot areas
• Junction box
• Discolored cell areas
• Bus bars
JUNCTION BOX
HOT SPOTS/AREAS.
Locating vermin to assist with vermin control.
Stock location on properties.
Crop health to assist the farmer to achieve a maximum yield.
Assisting with bushfire control by identifying hot spots with thermal images.
Power line and insulator inspections using thermal technology and videography.
Phone tower inspections.
Assisting in Search and rescue missions