In the world of electrical reliability, assumptions can be costly – and half-truths, even more so.
“Ultrasound can detect partial discharge.” It’s a claim you’ve probably heard before. But according to Josh Robinson, it’s only part of the truth. In his RED Talk, The Truth About Ultrasound and Partial Discharge, Robinson breaks down what that statement really means – and why repeating it without context is a problem for everyone in the field.
“It’s not a lie,” Robinson says. “But it’s not the whole truth. And that makes us all look bad.”
The episode dives into a persistent misunderstanding in the maintenance and inspection industry: that a single tool can detect every form of partial discharge. But PD isn’t a one-size-fits-all phenomenon. There’s surface PD – like arcing, tracking, and corona – and there’s subsurface PD, the kind of hidden insulation failure that leads to catastrophic equipment blowouts. Only one of those makes a noise that ultrasound can hear. So what happens when a technician relies on the wrong method – or a sales pitch that oversells its capabilities? What crucial warning signs are being missed?
Robinson uses simple, relatable analogies to make a complex topic click: a garden hose with a hidden pinhole; electrons “dripping” from a wire like a leaky tap.
His delivery is candid, a little irreverent, and deeply informed by hands-on experience. He doesn’t pull punches – especially when it comes to the gap between what tools can do and what they’re sold to do.
If you work with high-voltage equipment, if you spec out testing programs, or if you’ve ever had to sit through a product demo and wonder what’s real and what’s fluff – this is a talk you need to hear.
Robinson also introduces tools many in the industry overlook: TEV sensors, HFCT clamps, UHF blocks for gas-insulated switchgear. He doesn’t just point out the problem – he shows the right way to tackle it.
But more than anything, his message is a call for honesty. “I’d like to see sales guys who lie less,” he says. “Because when one person overpromises, it makes the rest of us look like we don’t know what we’re doing.” RED Talks features voices who challenge assumptions and move the conversation forward.
Josh Robinson’s episode is one of our sharpest yet – raw, practical, and grounded in real-world experience. No marketing gloss. No fluff. Just the kind of clarity that helps keep systems safe and reliable.
Think you already know what ultrasound can do? Watch this first.
Watch Josh Robinson’s RED Talk now.
This article was originally published in the September 2025 issue of the Substation Solutions: Design, Automation and Monitoring magazine.
View Magazine
