Substations require a predictive maintenance approach as a failure could spell disaster for consumers, in the form of lost revenues and production, and result in lower utility revenues from lost sales courtesy unreliable service. As overheating and also extremely frigid operating temperatures could signal electrical component degradation, thermal imaging tools offer predictive capabilities necessary for switchgear and substation maintenance.
Within the power distribution and generation industries, substation could be referred to or may get used in multiple ways. Different outdoor environments, right from equipment at industrial setups for modifying or switching voltage to generating station switchyards, characteristics such as frequency are referred to as substations.
Predictive maintenance (PdM) makes sure the end user’s electricity quality by improving substation reliability. PdM manages this enhanced reliability by regularly monitoring equipment for isolating conditions that signify impending failure.
The handheld thermal imager by Fluke is one among the tools that help monitor substation equipment. Thermal imagers gather 2D representations of electrical component and other object’s surface temperatures.
Need for Thermal Imaging
Almost all industrial and commercial facilities are prone to moisture intrusion, thermal loss, and machinery failure. Thus, having the right tool for tracking these issues is a must. Thermal imagers are almost synonymous with industrial and utility plants – commercial buildings have taken up to the technology only in recent times.
With the help of infrared wavelengths, the thermal imaging sensor helps measure an area’s thermal signature. The area could be as limited as an electrical box or as expansive as a complete building envelope. The output consists of a heat signature spectrum that’s not visible to the naked eye. This makes the tool invaluable for detecting hidden issues.
Fluke Thermal Imaging Features
The Fluke thermal imager has innovative functionality and features that makes it a much faster and efficient tool.
- IR OptiFlex: This exclusive focusing system ensures the images at a 4-feet or more distance are in focus to provide convenient measurements and optimal sharpness. For shorter distances, the focus could be switched to manual mode.
- IR PhotoNotes: This annotation system ensures you constantly have references for handing, identifying and keeping an overview of the sites inspected, by appending important information, surrounding areas and digital images.
- IR Fusion: This trademarked feature helps detect problems easier and faster.
- The CNX and Fluke wireless modules help take measurements easily and quickly from almost five wireless modules at the same time.
- Video capturing with several modes is possible too – with focus-free videos in infrared IR fusion and visible light.
- The built-in electronic compass lets you identify problematic spots quite easily.
Thermal Imaging Usage
For use, an electrician or qualified technician points the imaging tool at the spot or equipment under the scanner to look for unexpected spots. For capturing specific thermal pictures, the tool’s trigger is squeezed. Upon completing inspection, the captured images are uploaded to a computing system for detailed analysis, reporting, and later trending. Though the images are easy to interpret, only a qualified technician can best understand them. The following three aspects are to be noted during usage.
The inspected electrical equipment should be under a minimum of 40 percent nominal load for detecting issues with thermal imagers. If possible, maximum load scenarios are recommended.
Under NFPA 70E*, electrical measurement safety parameters are still applicable. Stepping in front of a live, open, electrical panel needs use of personal protective equipment (PPE). Based on the scenario and Bolted Fault Current (incident energy level) of the equipment under the scanner, the PPE could entail:
- Leather and rubber gloves
- Flame resistant clothing
- Face shield rated for arc flashes
Emissivity is how well the object gives out heat or infrared energy. This influences how well a thermal imaging tool can measure the surface temperature of the object. Every material and object has a particular emissivity that could be rated on a 0 to 1.0 scale. In case of thermal imaging for accurate temperature reporting, higher emissivity is preferred.
Warning Signs & Follow-Up
Before using the Fluke thermal imaging tool in a substation, scan the whole yard, saving pictures of known or possible oddities. Look around particularly for machinery under identical loading, which clearly function at different temperatures. A recommended thermographic substation maintenance approach entails creating inspection routes, including all substations coming under your facility or utility.
Equipment conditions posing safety issues must get highest priority repair. Going further, InterNational Electrical Testing Association (NETA) guidelines state when the difference in temperature between interchangeable elements under alike loading goes beyond 15 C, immediate repairs must be performed.
Whenever your thermal images detect an issue, use the linked software for documenting your conclusions in a report, including the equipment’s visual-light, digital image and a correlating thermal picture. This is probably the best method for communicating any issues found and making suggestions for corrections.