Electric motors are essential in industrial operations worldwide, powering factories, processing plants, and utilities. Frequent motor failures can halt production and lead to high repair costs. One major industrial client experienced repeated motor winding burnout, causing downtime and expensive maintenance.
Instead of replacing motors repeatedly, the client implemented power quality monitoring with the Hioki PQ3198-94 Power Quality Analyser, rented from TechRentals, to uncover the root cause and prevent future failures.
Challenge
Addressing Voltage Irregularities to Prevent Electric Motor Winding Burnout
While mechanical wear is often blamed for motor failure, voltage irregularities, harmonics, and transient overvoltages are frequently the true culprits. These disturbances can lead to:
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Insulation degradation
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Overheating of windings
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Reduced lifespan and repeated burnout
Pinpointing such issues requires precise, high-resolution power quality measurement, especially in large industrial environments across Australia, Singapore, Malaysia, and beyond.
Investigation
The maintenance team installed the Hioki PQ3198-94 Power Quality Analyser at the affected motor’s input terminals. Over several days, the analyser logged voltage, current, harmonics, transient spikes, and power factor, providing detailed insight into the power conditions during normal operation and load fluctuations.
Findings
Revealing the Hidden Electrical Stress
Analysis of the data revealed several key power quality issues contributing to the failures:
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Voltage and Current Imbalance
The PQ3198-94 identified voltage imbalance between phases, exceeding recommended thresholds and corresponding current imbalance. This caused uneven heating across motor windings, accelerating insulation wear. -
Harmonic Distortion
Total Harmonic Distortion (THD) in both voltage and current exceeded IEEE 519 limits, largely due to nearby Variable Frequency Drives (VFDs). These harmonics increased electrical losses and mechanical vibration. -
Transient Overvoltages
Short, high-voltage transients were captured during capacitor bank switching events, reaching nearly twice the nominal supply voltage. These spikes placed additional stress on the insulation system. -
Low Power Factor
The motor’s average power factor dropped below 0.7, indicating inefficient energy use and possible mechanical strain from degraded windings.
Root Cause and Corrective Measures
The data confirmed that voltage imbalance, harmonic distortion, and transient overvoltages collectively led to repeated winding burnout and overheating.
To resolve these issues, the plant implemented:
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Voltage correction equipment to stabilise supply
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Harmonic filters to mitigate distortion
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Surge protection devices to suppress transient spikes
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Motor replacement with upgraded insulation for added resilience
As a result, the client reported:
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A marked decrease in motor failures
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Lower maintenance and repair costs
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Improved uptime and process reliability
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Higher electrical efficiency due to reduced harmonic stress
From Reactive Repairs to Proactive Power Management
What began as a reactive investigation into repeated failures evolved into a proactive power quality management strategy. With continuous monitoring now in place, the maintenance team can detect and address electrical issues before they cause damage.
This case highlights how the Hioki PQ3198-94 Power Quality Analyser, available from TechRentals, empowers industries across Australia, Malaysia, Singapore, and neighbouring regions to move from costly reactive maintenance to predictive and preventive action.
Why Power Quality Analysis Matters Globally
Even small voltage irregularities can shorten motor life and increase energy consumption. By monitoring key parameters such as imbalance, harmonics, transients, and power factor, facilities can protect critical assets and improve overall efficiency.
The Hioki PQ3198-94 offers:
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High-precision measurement of voltage and current imbalance
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Harmonic and transient capture for in-depth diagnostics
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Waveform and event logging to pinpoint root causes
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Real-time analysis for immediate decision-making
Rent the Hioki PQ3198-94 from TechRentals
TechRentals provides flexible rental solutions for advanced testing equipment worldwide. The Hioki PQ3198-94 Power Quality Analyser is available for short- or long-term rental across multiple regions, helping industrial clients:
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Diagnose and prevent motor burnout
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Improve power quality
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Optimise operational efficiency
Click here to rent the Hioki PQ3198-94 Power Quality Analyser and protect your motors from downtime.
