Improving UPS Reliability

                                                                                                                         

The Parallel Redundant configuration is the most used UPS configuration in the world. However, it can be shown that the maintenance bypass switch introduces a single point of failure and thereby reduces the overall reliability. A maintenance bypass will be required to allow service and maintenance of the UPS system (so configured) without disconnecting the critical load from a power source. Likewise, a Hot-Tie configuration, which is two separate UPS systems joined by a static transfer switch, has a single point of failure at the switch. Such single points of failure significantly reduce system MTBF.

Regardless of the configuration, the system’s reliability can be dramatically degraded if it is poorly maintained. Since people cause 50% of all UPS system failures, the key to uptime is proper training of the operating personnel. Other key points for preventing such degradation are as follows:

  • Post clear, concise operating instructions
  • Regularly scheduled maintenance by qualified personnel
  • Knowledge of battery’s health and capacity
  • Circuit breaker coordination
  • Spares inventory
  • Test the availability of the backup AC sources
  • Participate in a product upgrade program with the UPS vendor
  • Place the UPS alarm where it must be acknowledged

About PS&C

Power Systems & Controls is a world leader in power quality and power protection technology, building systems for mission critical applications world-wide. Clients include many of the world’s leading research and test laboratories, rail and sea mass transit, advanced manufacturing, and data centers. The company was founded in 1965 by CAT. Today the company is headquartered in Richmond, VA and supports the USG and DOD, Fortune 500, and many other international organizations on a wide range of applications. We don’t just solve power problems; we engineer power solutions.

PS&C Power Quality Testing

                                                    

As a supplier of power conditioning equipment for critical real-time applications, Power Systems & Controls (PS&C) has learned the importance of change. Whether changes are due to additional load or new technology, our customers can rest assured that their equipment is capable of handling their needs. Due to problems that can arise when newer technology is coupled with the old, PS&C consistently strives to develop compatible service enhancements so that our customers’ critical loads are never compromised.

In the past, it has been common practice to document the performance of a UPS system at start-up. However due to the various power quality problems we’ve encountered over the years, PS&C is pleased to announce that we now offer a power quality monitoring service. In our continuous effort to maintain state-of-the-art test disturbance equipment, we have added monitoring equipment which collects and qualifies electrical data on almost every aspect of three phase power system. This includes voltage, current, frequency, impedance, power factor, demand and all other types of electrical disturbances.

PS&C offers this service to our customers of any others interested in avoiding or resolving power quality problems. PS&C will work with your facilities’ personnel or electrical engineer to collect accurate data independent of your equipment manufacturer. If the power quality study has not been done prior to equipment purchase, we recommend that it be conducted at start-up. For a small fee PS&C will provide a comprehensive power study which will serve as a baseline for your facility. The study should be updated each time major changes in equipment are made or every two years to document your current power system performance.

Another power quality issue of concern to the power conditioning industry is Total Harmonic Distortion or THD. The IEEE 519.1992 recommended standard outlines the amount of harmonic current that can be reflected to a power source. In addition to the above, the power study now offered by PS&C can also identify harmonic current sources to determine your overall power quality and tell you if your THD problems are self-induced.

About PS&C

Power Systems & Controls is a world leader in power quality and power protection technology, building systems for mission critical applications world-wide. Clients include many of the world’s leading research and test laboratories, rail and sea mass transit, advanced manufacturing, and data centers. The company was founded in 1965 by CAT. Today the company is headquartered in Richmond, VA and supports the USG and DOD, Fortune 500, and many other international organizations on a wide range of applications. We don’t just solve power problems; we engineer power solutions.

New Technology…Old Idea

                                                           

Almost fifty years ago, capacitors became popular for Power Factor Correction due to their low relative cost. However, recently companies have experienced problems with their capacitors. In many cases entire facilities need to have their power factor corrected. The act of correcting power factor must be seamless and cause no disturbances or oscillations within the facility. PS&C’s Series SC, Synchronous Condenser, has been designed to do just that.

The first step in the updating process was to add a “modern” power factor controller to regulate the field of the synchronous machine. The controller allows the user to adjust the corrected Power Factor of his load between .8 lagging and .9 leading. Once set, the controller adjusts the field of the synchronous machine to maintain the load at the desired power factor. The Series SC maintains the power factor under all conditions up to the kVAR rating of the machine. If the demand exceeds the SC’s rating, the synchronous condenser changes to a constant kVAR mode, thus delivering the maximum correction available.

The Series SC employs the latest in PLC and detector technology to make the user’s interface simple and direct. A feature resulting from the use of a PLC is its ability to automatically restart itself after a power interruption. This feature helps to minimize the fifteen-minute peak power demand factor. The combination of modern technology and the rugged design of the machine insures that the Series SC will provide reliable Power Factor Correction for many years to come.

About PS&C

Power Systems & Controls is a world leader in power quality and power protection technology, building systems for mission critical applications world-wide. Clients include many of the world’s leading research and test laboratories, rail and sea mass transit, advanced manufacturing, and data centers. The company was founded in 1965 by CAT. Today the company is headquartered in Richmond, VA and supports the USG and DOD, Fortune 500, and many other international organizations on a wide range of applications. We don’t just solve power problems; we engineer power solutions.

Electrical Market Needs Rotary

                                                     

PS&C has noticed increasing interest for Power Conditioning equipment to support less traditional markets. It seems that a majority of the new inquiries for power quality systems and services are being generated from industrial facilities. In many cases, they are from facilities that have installed new equipment on production lines. Industrial Facilities are subject to a variety of power problems. The most common are equipment shutdowns (affecting both the older systems, as well as, the new ones), voltage sags (both on utility & inside the plant), and harmonic distortion (caused by Adjustable Speed Drives/ASD).

In addition, we have heard of instances from various utility companies where neighbors of industrial plants have called to complain about disruptions to their power caused by the plants across the street. How does this happen? In most cases, it’s because the Industrial Plants have replaced older processing systems with newer, state-of-the-art systems. And while the new systems increase productivity improve quality and lower costs, they can also cause unexpected problems within the electrical system. These problems can be anything from improper equipment operation to complete equipment shutdown every time there is a minor disturbance on the electrical system.

PS&C has been witness to end users who try a range of solutions with varying degrees of success. One was to install new, very large Automatic Voltage Regulators, harmonic canceling transformers, Power Factor Correction capacitors, and small static UPS systems. In some cases, these devices not only didn’t work, they actually ended up causing more problems. Other solutions included correcting facility grounding problems, installing Motor-Generators for voltage regulation, and/or isolation from the power source, and removing capacitors and installing Synchronous Condensers to correct power factor problems without the danger of creating resonance points.

Just as the benefits of Hybrid Rotary UPS systems have made to computer power protection, large rotary systems can be the best value in many industrial applications as well. Static UPS systems, TVSS’s, and traditional power protection devices have their place but rotary systems offer abilities and performance benefits that other technologies are unable to do.

Power Systems & Controls has a state of the art production and test facility located in Richmond, VA allowing for easy access to Washington, DC and the east coast. PS&C has the unique ability to support both static (solid-state) and rotary (motor generator) UPS, frequency converter, and power conditioning requirements as we are one of the few companies in the world that manufactures both types of technology. Power Systems & Controls is an employee owned company and has a long history of successfully supporting mission critical applications across the world.

About PS&C

Power Systems & Controls is a world leader in power quality and power protection technology, building systems for mission critical applications world-wide. Clients include many of the world’s leading research and test laboratories, rail and sea mass transit, advanced manufacturing, and data centers. The company was founded in 1965 by CAT. Today the company is headquartered in Richmond, VA and supports the USG and DOD, Fortune 500, and many other international organizations on a wide range of applications. We don’t just solve power problems; we engineer power solutions.

Synchronous Condenser Excels

                                                     

A key reason for purchasing a Series SC Synchronous Condenser is to reduce the cost of power by reducing the user’s power factor. Unlike other methods and products available for power factor control, the Series SC is both automatic and seamless in its operation. The control logic automatically adjusts its VAR output to maintain the user’s power factor at the preset level. These changes occur without causing glitches or transients to the user’s power. Since its operation is totally without transients, it cannot upset any of the user’s critical operations.

Beyond the technology needed to accomplish its intended task, the Series SC has many user friendly enhancements. One feature available is the automatic restart after power loss. When a power outage occurs, the Series SC waits one minute beyond the return of utility voltage with acceptable tolerances. This waiting period delays the starting current beyond the start-up of other critical equipment. Ten seconds before the actual restart, the Series SC turns on its alarm to warn of an impending restart. If the utility voltage should fall out of acceptable limits during the restart, it waits another minute before attempting to restart a second time. If the unit is unable to start then, it turns on its alarm and ceases trying. At this point the utility fault is significant and repeated restart attempts are futile. After power is restored, the Series SC can then be started manually.

The PS&C Synchronous Condenser has a touch screen display and interface which are the latest in display and control technology. The controls are friendly and easily understood so that the user can control the unit from this panel. The touch screen will display voltage, current, power factor, and power information. Internally, it has several serial busses. These can be used to deliver data to the user’s monitoring system. Status and fault data, values of the voltages, currents, power factor, etc. are available.

Power Systems & Controls has a state of the art production and test facility located in Richmond, VA allowing for easy access to Washington, DC and the east coast. PS&C has the unique ability to support both static (solid-state) and rotary (motor generator) UPS, frequency converter, and power conditioning requirements as we are one of the few companies in the world that manufactures both types of technology. Power Systems & Controls is an employee owned company and has a long history of successfully supporting mission critical applications across the world.

About PS&C

Power Systems & Controls is a world leader in power quality and power protection technology, building systems for mission critical applications world-wide. Clients include many of the world’s leading research and test laboratories, rail and sea mass transit, advanced manufacturing, and data centers. The company was founded in 1965 by CAT. Today the company is headquartered in Richmond, VA and supports the USG and DOD, Fortune 500, and many other international organizations on a wide range of applications. We don’t just solve power problems; we engineer power solutions.