Ever wondered how a “high-efficiency” motor can start wasting energy and damaging bearings before it’s even been switched on?

We did too. So we tested it.

Using offline motor circuit analysis alongside online motor current signature analysis, we inspected brand-new IE4 motors still sitting in their crates. What we found changed the conversation completely. Critical impedance imbalance straight out of the box. One motor already showing early winding defects before it ever saw load.

That’s the moment labels stop mattering and evidence takes over.

This episode walks through why pairing de-energised and energised testing matters.

Offline MCA tells us what’s happening in the windings – contamination, resistive imbalance, insulation condition. Online MCSA, sampled at 44 kHz with serious resolution, shows us what vibration often can’t: rotor bar issues, air-gap problems, electrical harmonics, inverter-driven bearing currents.

In difficult environments – noisy plants, submersible pumps, generators, limited access assets – current signature analysis often gives cleaner, more repeatable insight than vibration alone. We’re seeing faults that used to hide in the noise.

And this isn’t theory. Across 750+ motors tested in the field, we see a clear link between impedance imbalance and winding health:

• <5% – normal
• 5–8% – defect initiation
• 8–15% – accelerated damage
• >15% – critical

That gives teams something powerful: defensible alarm limits and a simple acceptance test that stops bad assets entering the plant.

There’s a practical win too. On one motor we reduced resistive imbalance from over 30% down to around 3.8% just by cleaning and correctly torquing the terminations. Test. Fix. Retest. Immediate improvement.

The real gains come when sites take this seriously:
Acceptance testing written into purchase orders.
Evidence required from the factory.
Faults confirmed using at least two technologies.

That’s how you reduce energy loss, prevent shaft currents from destroying bearings, and turn condition monitoring into real reliability improvements – not reports that sit on a shelf.

If uptime matters.
If energy efficiency matters.
If you want better decisions with less noise and less drama.

This episode shows the path: measure what matters, set your own standards, verify the fix, and keep learning.

Enjoy the episode.
If it helps you rethink your motor strategy, subscribe, share it with a teammate, and drop a quick review with your biggest testing win or surprise.

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Reliability doesn’t fail because the maths is wrong. It fails because of people. That’s where we begin this straight-talking conversation with Steve Morris, the driving force behind Mainstream. For more than 30 years he has been building something different: a movement that puts real maintenance leaders on stage, replaces the hero firefighter with predictable performance, and keeps the community alive all year round so practitioners can share what actually works without the sales pitch.

We look back at where it started, from a handful of TPM calls to what has grown into the biggest reliability conference in the Southern Hemisphere. But what makes it stand out is how it protects the quality of the peer group, only puts customers on stage, and is built on research that identifies the real blockers—communicating risk, finding funding, and leading culture change. Steve lifts the lid on innovation theatres, curated networking, and the free online platform that now connects more than 5,000 professionals across industries. From mining and water to food and oil and gas, the challenges are different but the root causes are the same—people, incentives, language, trust, and habits.

We also look ahead to Mainstream UK. This will be a focused two-day event with five concurrent tracks, global storytellers from Woodside to Mars, and pricing that removes the excuses. If you have ever felt your best preventative work goes unseen while the 2am saviour gets all the recognition, this is your chance to flip the script. It is about rewarding prevention, learning how to sell the value in finance’s language, and being in rooms where practitioners lead the conversation.

The next five years are critical for reliability. Teams are ageing, technology is moving fast, and the skills gap is widening. The advantage will go to those who make the time to think, to share, and to adopt what already works.

If this resonates, subscribe for more conversations with reliability leaders, share the episode with your team, and leave a review so others can find it. Most importantly, connect with the Mainstream community and take one idea back to your site this month.

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When most people think reliability, vibration analysis is the first thing that comes to mind. But what about the electrical side of your motors. That’s where a lot of hidden damage is happening and it’s often ignored.

In this episode we get into shaft current. It’s been around since variable speed drives first hit the scene but it’s still not well understood and definitely not well managed. These stray electrical currents eat away at bearings and windings, quietly cutting motor life down by decades. The scary part is that from what we are seeing around 90 percent of drive installs haven’t been designed properly to deal with it.

I reference the teachings of electrical condition monitoring expert Mark Gurney to break this down. We look at how to actually detect the issue with oscilloscopes, Rogowski coils and the SKF TechEd tool. We explain the difference between common mode and circulating currents and why quick fixes like grounding rings aren’t always the silver bullet people think they are. Done wrong they can even make the problem worse.

We also talk about Motor Current Signature Analysis MCSA. For me this is the future of motor testing. It gives you the ability to pick up not just electrical faults but mechanical ones too. Bearings rotor bars even belt tension can all be identified just from reading the motor’s electrical signal at the MCC. If you’re serious about IoT and advanced monitoring MCSA is a game changer compared to just scattering sensors everywhere.

The bottom line is this. Why are we okay with motors failing after 10 years when they are designed to run 30 or 40. It’s time to move beyond only looking at vibration and start treating electrical testing as a key part of reliability. Our most critical assets deserve that level of care.

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