top of page

Acoustic Ultrasound Solutions for Electrical Inspection

Airborne and structured-based (A&SB) ultrasound can be used to detect various electrical faults; including corona discharge, tracking, and arcing. The PowerBeam 300 parabolic accessory allows the technician to locate sources of ultrasound with pinpoint accuracy from distances up to 300 feet away. Additionally, the InCTRLplatform and InCTRL mobile app can be used to record samples, store testing history, and communicate faults through a management chain. InCTRL's FFT spectral analysis feature can be used to diagnose recorded samples for electrical failures.



Power Transmission and Distribution


The UL101 Electrical Inspector and PowerBeam 300 are used together to inspect medium and high voltage power lines, switchgear, and transformers. Inspection focuses the detection of corona, which is a symptom of two types of failures including material degradation and indeterminant by other technologies. The UL101 Electrical Inspector is very affordable and very effective in all types of environments for these tasks.


"India's Certified R&D Institute has certified the functional aspects of CTRL UL101 [Electrical Inspector] with the PowerBeam 300 for detection of corona discharge from 400 kV single suspension insulator string consisting of 1 x 25 Nos. of 120 kN B/s discs with arcing horn and corona control ring and 245 kV single suspension insulator string consisting of 1 x 14 Nos. of 120 kN B/s discs with arcing horn and corona control ring. Readings were taken by the UL101 and PowerBeam 300 from 50, 100, and 150 feet respectively."


How to Inspect Transmission Lines


  1. Scan the Electrical transmission system network such as Insulator or cable string with the CTRL UL101 Electrical Inspector and PowerBeam 300 attachment.

  2. The UL101 Electrical Inspector will pick up the ultrasound signal which is generated at the source due to electrical arcing, tracking, or corona discharge.

  3. If there is a continuous corona effect during transmission near the insulator, it results in transmission losses.

  4. The intensity of the ultrasound will increase as you direct the PowerBeam 300 scan the area, allowing you to pinpoint which insulator is punctured or damaged.

  5. In most of the cases, a punctured insulator or coated insulator produces the high intensity ultrasound rather than emitting heat. Thus ultrasound is very effective in these applications to detect corona/arcing over other methods.

"This method of detection during day time is added advantage over other methods like infrared imaging."


The PowerBeam 300 is very effective from 66 KV to 440KV Electrical system for finding out the faults with following applications:

  • Broken Strands

  • Loose Hardware

  • Improper Installations

  • Damaged or Punctured Insulator

How to Inspect Electrical Panels


Safety is the first line of defense. Scan cabinets & MMCs with panels closed. Use the CTRL UL101 Electrical Inspector together with a airborne attachment.


Step 1: Scan with UL101 Electrical Inspector

Listen for arcing and discharge with panels closed.


Step 2: Determine if Arcing Present

Easily hear the arcing sounds from a safe distance


Step 3a: Open Panels with Confidence

Safely open panels with appropriate PPE


Step 3b: De-Energize if Questionable

High levels of ultrasound indicate severe problems