Each infrared inspection that we do is preceded by an ultrasonic inspection as a routine measure. We feel that this is an important addition in our endeavor to keep you, your employees, your facility and all personnel as safe as possible. An ultrasonic inspection can detect corona, arcing and tracking in enclosed spaces and will help reduce the potential for both personal injury and equipment downtime.
Various electrical conditions emit sound waves that are difficult or impossible to detect without the use of listening devices. These ultrasonic waves give proof of the existence of various electrical problems that are potentially dangerous. Corona, electrical arcing, electrical tracking and leaks in compressed air systems can be located through ultrasonic inspections.
Ultrasonic Inspections are a “No-Brainer”
- Energy savings are realized instantly
- Compressor workload and cycle times are greatly reduced
- Machinery will run more efficiently
- Accounting will love the savings!
- In a 100-psi system a number of small leaks totaling 3/8 inch will waste 6,671,090 cubic feet of air per month and costs over $1,668 to produce
- That would be an annual savings of more than $20,000 (based on $.25 per 100 cubic feet)
We can inspect:
- Breakers of all types
- High voltage transmission lines
- Underground vaults
- Circuit breakers
- Bus bars and risers
- Electronic devices
- Even when metal-clad enclosures cannot be opened, airborne ultrasonic inspection equipment can “listen” through enclosure openings and vents.
How Corona Can Affect You
Corona is a phenomenon that can degrade insulators in your equipment, causing systems to fail.
What is corona? Webster defines it as “a discharge, frequently luminous, at the surface of a conductor or between two conductors of the same transmission line, accompanied by ionization of the surrounding atmosphere and often by a power loss.”
Once corona starts, the voltage must be decreased to get it to stop. When trouble-shooting this phenomena, many of the natural senses are used. You can often hear a hissing or cracking sound. That is why stethoscopes or ultrasonic detectors can be used to find corona. Sometimes its presence can even be detected by a distinctive odor that indicates the presence of ozone which was produced by corona.The effect is that it will degrade insulation, reducing the reliability of the system. Since corona is a low-energy process, over long periods of time it can substantially degrade insulators, causing a system to fail. The effects are cumulative and permanent and failure can occur with no previous warning.
Causes of Corona
- Ultraviolet radiation
- Salts (white powder deposits)
- Nitric or other acids
- Various chemicals
- Sound (hissing, cracking)
- Heat—primarily in the insulator
- Carbon deposits
- Mechanical erosion of surfaces