All power quality articles
For three years in a row, a particularly large three-phase motor would fail twice a year. The facility maintenance manager called in both the electrical contractor and the motor manufacturer, who pointed fingers at each other but failed to resolve anything on site.
Monitoring three-phase power quality is a must. Whether you troubleshoot mysterious electrical problems or provide additional services to a client, it is three-phase power that is provided to commercial and industrial customers and three-phase power that is distributed throughout a facility.
Troubleshooting the most common power quality problems—voltage distortion and harmonics. Tools needed, types of problems
At the end of April 2005, Crystal Mountain Resort in Washington suffered catastrophic failure of two power filters associated with their chair lifts.
Many facilities, such as power plants or production facilities, depend on a strong preventive maintenance program. These programs are essential to keep processes running safely and efficiently.
Ever fixed something and still not solved the problem? Sometimes multiple deficiencies can all cause the same symptoms.
Because power quality issues are difficult to pinpoint, clients often reach the wrong conclusions about their power issues. That often leads to expensive solutions that don't actually correct the underlying problem.
A large commercial building had just finished an elevator equipment upgrade - but they hadn't been able to bring the elevator back into normal operation.
This case history comes from an electrical contractor. Several of this contractor's clients operate large commercial buildings.
Motor failures can be mysterious. Often, the mechanical loads on the motors have not changed and other loads connected to the same service appear to work normally - yet, the motors just fail.
This case history involves the investigation of a utility transformer failure that occurred in a rural area surrounded mostly by farmland and open space. The failure occurred in a location where power quality problems are rare.
One winter morning, the electrician received a call from a local school. The caller said a transformer supplying power to three portable classrooms was making a chattering noise, as if something were loose inside.
A small city gets its water from a mountain lake 30 miles away. A pumping system at the lake brings water up a short incline and into a long gravity pipeline that feeds the city's water distribution system.
The engineer carries a Fluke 43B on all trouble calls, because it provides a graphical display that allows customers to see a picture of the problem.
In most facilities, lighting is a major element of operating cost. Part of that cost is due to energy, and part is due to maintenance.
This case history is a classic example of the importance of a systematic approach to solving a problem. It involves a contractor who works with several high-technology manufacturing plants.
Maintenance electrical specialist Mark Newport was in the process of installing new electronic power factor correction units at multiple motor control centers (MCCs) to improve power quality, protect equipment and reduce costs.
You could almost call it a happy accident. During a routine job at a large industrial facility, an electrical maintenance worker set a plastic kit on top of a nearby transformer.
After experiencing some nuisance tripping of breakers in the subpanel feeding the second floor of this industrial building, we installed a Fluke 1750 Power Recorder at the subpanel to gather information about power usage.
A ski resort near Silverthorn, CO., depends on its snowmaking capacity to augment nature's snowfall, especially during drought years.
Filmwerks International is one company that has implemented a better way to monitor utility power for their backup UPS systems and generators
Critical systems run smoothly with regular maintenance and reliable tools Everybody knows that consistent, dependable electrical power is critical to any plant's function. But perhaps even more critical is a reliable uninterruptible power supply (UPS) system. UPS systems are the silent partners that just sit and wait until there's a break in power. At that point, the UPS system is the most important system in the plant. It has to be ready to spring into action in milliseconds to keeps things running for anywhere from seconds to hours.
Downtime is costly, both in terms of patient wellbeing and monetary costs - the X-Ray, mammography, and other systems themselves cost millions and a failure can also idle technicians or surgical teams. Most of the facilities have motor/generators and can maintain operations independent of the utility, making the power system robust but also complex.
Watch the video to see how the Point Defiance Zoo and Aquarium uses the Fluke 438-ii power quality analyzer and motor analyzer to reduce water and energy use.
Mac McArthur performs power quality studies for commercial, industrial, and residential clients.
It was in his capacity as an electrical troubleshooter and an electronics expert that Gagne, almost two years ago, first began to use a Fluke 434 Power Quality Analyzer and a Ti30 Thermal Imager.
Troubleshooting an electrical panel overheating problem from unusual causes; testing with the power on, ruling out harmonics—and the resolution.
Learn the difference between single-phase and 3-phase power supplies, including uses and configurations.
What is power factor and why is it important? Learn how to calculate the power factor formula, each component of the equation, and why it matters.
Why monitor power consumption with a power logger? Get the data you need to make important energy management decisions including plant safety, cost savings, and power quality troubleshooting.
To determine the best solution for mitigating unwanted harmonics, start by investigating the equipment suspected of producing the bulk of the harmonic currents. Most often these are Variable Frequency Drives (VFD's). Use measuring equipment to measure and analyze the frequencies and amplitudes of the harmonics. This is much simpler than it sounds.
Transformers supplying nonlinear loads should be checked periodically to verify operation within acceptable limits. Transformers are also critical to the integrity of the grounding system.
The electrical power issues that most frequently affect industrial plants include voltage sags and swells, harmonics, transients, and voltage and current unbalance. The proper tools to correct these issues include knowledge and electrical test instruments ideally suited for each task.
Power factor correction capacitors reduce energy costs by avoiding the premium rates that utilities charge when power factor falls below specified values.
Since information technology (IT) installations are particularly sensitive to power supply fluctuations and distortions, they typically rely on an uninterruptible power supply (UPS) to compensate. Some installations even include a second UPS supplied by a separate feeder, and a standby generator that can be set to start automatically three minutes after detecting a power interruption.
Electrical noise is the result of more or less random electrical signals getting coupled into circuits where they are unwanted, i.e., where they disrupt information-carrying signals.
Voltage sags, tripping breakers, overheated electrical panels, and excessive voltage levels are all indications of possible trouble in an electrical distribution system.
Rely on the Fluke 120B Series Industrial ScopeMeter® Handheld Oscilloscopes when your work calls for detailed and accurate signal measurements.
Learn how to improve power factor, including specific solutions for different root causes of poor power factor.
Detect basic 3 phase power quality issues with the versatile Fluke 378 FC clamp meter for industrial electricians. Increase productivity and safety without test leads.
Learn why on all current clamps and current clamp accessories, there is an arrow placed close to the beak or inside the beak opening.
Learn how to diagnose power quality issues in older electrical systems using a Fluke multimeters and oscilloscope.
Power quality measurement is still a relatively new and quickly evolving field. Whereas basic electrical measurements like RMS voltage and current were defined long ago, many power quality parameters have not been previously defined, forcing manufacturers to develop their own algorithms.
This application note details the procedures for using Fluke power quality analyzers for average watt measurements and converting those to watt-hours.
The most important step in any measurement process is setting up your measurement device correctly. Do this incorrectly and you can find out your data is useless after a measurement cycle of days or weeks. That means starting all over again—if you can.
How to find the root cause of production line stoppage and reduce downtime in manufacturing.
Many power quality problems show up at the branch circuit level. There's a simple reason for this: that's where most of the sensitive loads (and sensitive employees) are located.
Three organizations found cost and time savings after implementing the Fluke 3540 FC Three-Phase Power Monitor into their maintenance programs.
Measuring output torque without mechanical sensors
The need to manage power is never more critical than when power prices skyrocket and power quality becomes suspect.
In troubleshooting situations involving a motor, more than half the battle is simply isolating the problem.
Adjustable speed drives (ASDs) can be both a source and a victim of poor power quality.
The Power Of A Waveform: Expanded Troubleshooting Options With The Fluke 345 Power Quality Clamp Meter
Electricians are discovering that the new Fluke 345 goes beyond simply monitoring voltage or current. It displays waveforms and harmonics, performs power measurements for power-factor evaluations, measures inrush current, and logs data over time for later analysis.
How to diagnose a high voltage surge arrester with a Fluke thermal imaging camera.
Diagnosing and troubleshooting power quality issues in medical equipment in hospitals and health care facilities.
Extend motor drive production performance, trend data over time and troubleshoot excess energy consumption. Compare the 438-II Power Quality and Motor Analyzer and the Fluke MDA-550 Motor Drive Analyzer.
When optimizing productivity in industry, energy use is one of the few inputs you can readily control.
“Let's just oversize the motor and we can run it lightly loaded—that will save us some money and be easier on the motor.” This is a false belief among some who select and install motors. Properly sizing motors for a given load results in driving loads more efficiently, saving energy, and saving dollars. Motors typically are most efficient when they are 90 % to 95 % loaded. Just because a motor says “25 Hp” on the nameplate does not mean the motor is producing twenty-five horsepower as it operates.Clamp meter readings: Problems and Solutions
Healthy batteries should main¬tain a capacity above 90 % of the manufacturer’s rating; most manufacturers recommend replacing the battery if it falls below 80 %. A series of regular tests are recommended for ensuring that batteries are maintaining capacit
Measure torque while motors are still in service using an advanced tool that eliminates external torque and speed sensors.
The Fluke 1738 Advanced Three-Phase Power Logger automatically captures and logs more than 500 power quality parameters to give electricians and technicians more visibility into the data needed to make better power quality and energy consumption decisions.
Power reliability for facility managers (bottom line): top issues; adds, moves, changes; electrical and electronic loads; emergency power; older facilities
Voltage stability may be a problem in areas where loads are cycling on and off during the day. Large compressors, motors, welding machines, arc furnaces, power factor correction capacitors and other large electrical machinery along with system impedance can easily cause voltage dips, swells, and transients.
As we have seen, power problems have a bad effect on electronic devices. To detect a power problem, a technician will first check out the power supply to a device to make sure it is functioning properly.