Why You Should Analyze Elevator Mainline Power—and Act on Harmonics

Are you experiencing frequent elevator breakdowns, mysterious shutdowns, or flickering lights near your elevator equipment? The culprit might be poor elevator power quality. As an elevator consultant since 2007, I’ve discovered that 32% of modern elevator controller issues stem from “dirty power” problems.

In this guide, you’ll learn how to identify elevator power quality issues, understand why they matter, and discover proven solutions to fix them.

What Is Elevator Power Quality?

Elevator power quality refers to how clean and stable the electrical supply is to your elevator system. Poor power quality, often called “dirty power,” can cause serious problems for modern elevator equipment.

Modern elevators use sophisticated Variable Frequency Drives (VFDs) instead of simple contactors. While VFDs provide smooth rides, they create electrical disturbances called harmonics. These harmonics distort the normal electrical waveform and can damage equipment.

The Hidden Cost of Poor Power Quality

When elevator power quality is poor, you’ll likely experience:

• Frequent nuisance shutdowns
• Shorter equipment lifespan
• Higher maintenance costs
• Potential safety issues
• Utility company penalties

Why Elevators Create Power Quality Problems

Understanding Harmonic Distortion

A standard 6-pulse elevator VFD produces 35-55% total harmonic distortion (THD-I) at rated load. This means the electrical current becomes severely distorted instead of flowing as a clean sine wave.

These distortions create harmonic frequencies (5th, 7th, 11th) that “ride” on top of the normal 60 Hz power. IEEE 519-2022 standards limit both current and voltage distortion to protect electrical systems.

Real-World Impact on Your Building

Poor elevator power quality affects more than just the elevator:

Controller Reliability Issues:

• DC-bus ripple stresses capacitors and power components
• Harmonic torque pulsations increase motor temperature
• Equipment triggers false overspeed or overcurrent trips

Building Electrical Problems:

• Extra heating in electrical feeders and transformers
• Neutral conductors can carry 170% of normal current
• LED lighting flickers throughout the building

Safety System Interference:

• Programmable controllers (PLCs) may reset unexpectedly
• Ground-fault systems trigger false alarms
• Fire safety systems experience communication errors

Financial Consequences:

• Utility companies impose penalties for poor power quality
• Increased energy costs from electrical losses
• Expensive emergency repairs and downtime

How to Test Elevator Power Quality

Why Power Quality Surveys Are Essential

Testing elevator power quality isn’t optional—it’s critical for:

• Proving new installations meet specifications
• Establishing baselines for future troubleshooting
• Identifying problems before they cause shutdowns
• Understanding system-wide electrical interactions

Recommended Testing Setup

For accurate results, use this testing approach:

• Three-phase power quality analyzer with one-second data logging
• Monitor all phases and neutral conductors
• Test at multiple points: service entrance, elevator disconnect, and VFD input
• Record data for at least one week to capture usage patterns

Elevators often share electrical systems with HVAC drives, UPS systems, and LED lighting. A comprehensive survey shows which equipment creates harmonics versus which equipment suffers from them.

Solutions for Elevator Power Quality Problems

When testing reveals high harmonic distortion, several proven solutions can restore proper elevator power quality:

Quick and Affordable Fixes

Install 5% Line Reactors

• Lowest cost option for immediate improvement
• Typically reduces THD-I to 25-40% range
• Easy to retrofit on existing systems

Add Tuned Passive Filters

• Usually targets 5th-order harmonics
• Reduces THD-I to approximately 10-18%
• Monitor power factor changes at light loads

Advanced Solutions for Severe Problems

Upgrade to 12-Pulse or 18-Pulse Drives

• Uses phase-shift transformers to cancel harmonics
• Achieves 10-15% THD-I performance
• Good long-term solution for new installations

Active Front End (AFE) Drives

• Near-perfect power quality (≤5% THD-I)
• Provides regenerative braking capability
• Highest upfront cost but best performance

Parallel Active Harmonic Filters

• Ideal when multiple drives share electrical systems
• Maintains IEEE 519 compliance limits
• Adaptable to changing building loads

Harmonic-Mitigating Transformers

• Delta-wye configuration diverts problematic currents
• Reduces neutral conductor heating by 40-80%
• Effective for buildings with neutral conductor issues

Why Professional Analysis Matters

Elevator power quality analysis requires specialized knowledge and equipment. Many building owners attempt DIY solutions that fail because they don’t address the root cause.

Professional analysis provides:

• Accurate measurement of all harmonic frequencies
• Proper sizing of mitigation equipment
• Compliance verification with IEEE 519 standards
• Documentation for utility companies and inspectors

Take Action on Elevator Power Quality

Don’t wait for costly breakdowns to address elevator power quality issues. Proactive testing and mitigation protect your investment and ensure reliable operation.

Signs you need immediate power quality testing:

• Frequent elevator service calls
• Unexplained controller faults
• Flickering lights near elevator equipment
• Ground-fault system false alarms
• Utility company power quality complaints

Get Professional Help

Analyzing elevator power quality isn’t optional maintenance—it’s critical insurance for passenger safety, equipment longevity, and regulatory compliance. When surveys reveal harmonics above specification limits, act quickly with proper mitigation solutions.

Need expert elevator power quality analysis? Argon Elevator Consulting provides complete testing services, data interpretation, and mitigation recommendations. We install data loggers, analyze results, and deliver actionable plans to keep your elevators running smoothly.

Contact us today for professional elevator power quality assessment and solutions that protect your building’s electrical systems.