Why Your Industrial VFDs Are Failing — And How to Prevent It

A failing variable frequency drive (VFD) doesn’t always announce itself with a dramatic shutdown. Sometimes, it’s a slow decline — overheating here, inconsistent performance there — until one day, your equipment grinds to a halt. VFDs are built to last, but even the best systems can fail when overlooked maintenance or common stressors creep in. The good news? Many failures are avoidable with the right maintenance.

The common culprits behind VFD failure

VFDs are complex, but the issues that take them down tend to be surprisingly straightforward. Identifying these common VFD failure points can save time and money — and plenty of frustration.

• Overheating. Heat is the enemy of electronics. VFDs rely on proper ventilation, clean air filters, and controlled ambient temperatures to avoid thermal stress. When airflow is blocked or cooling fans fail, components degrade faster, leading to premature breakdowns.
• Electrical surges. Power fluctuations, voltage spikes, and unstable grid conditions put immense stress on VFD circuits. Without proper surge protection, sensitive components can fry in an instant.
• Loose connections. Vibration, thermal cycling, and general wear can loosen electrical connections over time. A single loose terminal can cause erratic drive behavior or, worse, complete failure.
• Contaminants. Dust, moisture, and corrosive particles can infiltrate a VFD cabinet, leading to short circuits and internal component damage. Enclosed environments don’t guarantee protection — regular inspections are important.
• Improper programming. A VFD is only as good as its settings. Incorrect parameters, mismatched motor configurations, or overlooked safety limits can cause inefficiencies, excessive wear, and unexpected shutdowns.

How to extend the life of your VFDs

The best way to deal with VFD failures is to stop them before they start. Preventive maintenance and smart operational strategies can significantly extend the lifespan of your drives.

• Prioritize cooling and ventilation. The best way to ensure proper airflow is by keeping vents and filters clean. A clogged air path leads to overheating, which shortens the lifespan of internal components. And if a VFD is installed near heat-generating equipment, repositioning or additional cooling measures may be necessary.
• Protect against power fluctuations. Install surge protectors and line reactors to shield VFDs from voltage spikes and electrical noise. Regularly inspect grounding connections to prevent electrical instability.
• Perform routine connection checks. Periodically tighten terminal connections to counteract loosening caused by vibration and temperature fluctuations. Also, inspect wiring insulation for signs of wear, discoloration, or cracking — early intervention prevents larger electrical failures.
• Keep contaminants at bay. Sealed enclosures help prevent dust and debris from harming VFD components. In areas prone to moisture buildup, use dehumidifiers or other climate control solutions.
• Verify programming and settings. Double-check motor parameters and load configurations to match your application needs. Small setting errors can cause unnecessary strain on the system. Periodically review VFD logs and error codes to catch minor issues before they escalate.

Knowing when a VFD needs repair or replacement

Even with the best maintenance practices, no VFD lasts forever. The challenge is recognizing when a repair is the right call — or when replacing the drive is the better long-term investment. Some of the signs your VFD needs professional attention include:

• Frequent fault codes despite proper settings and load conditions.
• Unusual noises from the drive or connected motor, such as humming, clicking, or whining.
• Intermittent power loss or unexpected shutdowns without clear cause.
• Visible damage to components, like burned connectors, bulging capacitors, or corroded circuit boards.

Get an expert opinion on VFDs

Not sure if it’s time to repair or replace your VFD? GES can help. We’re experts when it comes to Repair, Sales & Service of VFDs. In fact, now through the end of the month, we’re offering 10% OFF single repairs or 15% OFF 3+ repairs of Allen-Bradley VFDs!

Don’t wait to seek VFD repair

When a VFD goes down, the clock starts ticking on lost productivity. That’s where expert repair services come in. At GES, our technicians specialize in diagnosing, repairing, and restoring industrial VFDs with precision. Whether it’s a failing power module, a programming error, or a full drive failure, we ensure your equipment gets back to full capacity — quickly and reliably.