Protecting the process through power conditioning
20/09/2013 POWERVAR Ltd
When failure is not an optionEnsuring the best possible customer experience
In the developed world, we enjoy remarkably reliable power supplies - typically available for 99.99% of the time. Businesses generally understand the need to ensure continuity of suppy by installing a UPS (uninterruptible power supply) to support critical items of equipment, such as electronic point of sale (POS) positions in shops and restaurants, mass spectrometers in analytical laboratories, ATMs in banks and so on. But many businesses are generally not aware that even continuous power can carry a great many impurities through the line which can possibly cause sudden damage to equipment, but more frequently results in disruption to operations and hidden wear that will ultimately result in the failure of critical components.
These problems with electrical power have many sources. Some have to do with the utility providing inadequate power at times, like brownouts and outages; others may be closer to home such as overloaded transformers, circuits, blown circuit breakers, or it could be electrical loads which create disruptive electrical noise, surges, and voltage spikes.
The effects of these problems may not always have immediate signs. Often a vital piece of equipment fails without any obvious cause.
In this white paper, POWERVAR explains how power conditioning systems provide clean, reliable power which plays a vital role in protecting the process by ensuring the correct operation of a wide range of sensitive electronic equipment across many different market sectors including:
-€¢ Medical and healthcare systems; this includes clinical and diagnostic equipment, patient monitoring, patient imaging and cardiac catheterization, among others
-€¢ Analytical instrumentation; gas chromatography, liquid chromatography, mass spectroscopy and explosive detection
-€¢ Banking and retail markets; including point of sale, ATMs and kiosks
-€¢ Electronics manufacturing - semiconductors, industrial automation, PCB manufacturing and automated test equipment
-€¢ Graphics and printing industries; page layout and makeup and digital feed presses
The goal of installing power conditioning equipment must always be to ensure the best possible customer experience with a focus on protecting the process. When OEMs install power conditioning equipment on their systems one of the largest benefits they can receive is gaining a competitive advantage over other suppliers that do not understand the importance of protecting the process.
The changing power environment
There are three main reasons why manufacturers of sophisticated electronic equipment need to pay increased attention to power quality.
First, the actual power supplies that are being used are getting less expensive and have switched from traditional linear mode power supplies to switched mode power supplies. These are much more susceptible to allowing high frequency noise to pass through.
Second, computer electronics are running at higher processor speeds, which mean they are more susceptible to line noise increasing the risk for soft failures and unexpected system lockups.
Third, a majority of today's systems are networked together so power quality issues are caused not only by the connected mains but also caused by the connected IT networks, creating more complexity in keeping them reliable.
On the solution side, equipment that claims to improve power quality is getting cheaper. But unfortunately, it does not address all the key issues. True power conditioning equipment does have a higher initial cost. But ultimately it delivers value by reducing the total cost of ownership of the entire system - by eliminating system lockups and premature component failure.
POWERVAR's philosophy is based on the ABCs of power conditioning (see appendix). Many inexpensive solutions only offer A - a surge diverter and E - a battery. True power conditioning requires ABC as a minimum - a surge diverter, low-impedance isolation transformer and noise filter.
The 3Ds of power quality
Power problems affect systems in three ways - destruction, degradation, and disruption.
Disruption
Disruption is the result of power disturbances that cause the electronic system to make the wrong decisions. Disruption also occurs when neutral to ground (common mode) voltages become excessive. Another major cause is the presence of ground loops in the network; these cause data communication errors and slow system throughput. These disruptive events are difficult to identify and can be easily mistaken for software bugs or operator errors. They are the most common cause of 'no trouble found' service calls.
Degradation
Degradation happens when lower amplitude power disturbances enter an electronic system and affect semiconductors at a microscopic level. Solid state devices are designed to operate at low voltages while degrading power disturbances will often exceed the material's voltage tolerances causing its erosion (rather like the way that rust damages metal) weakening the semiconductor. This damage is cumulative and occurs over time and as the result of a number of disturbances during which the material grows weaker until it ultimately fails with no previous warning, making the cause hard to identify.
This becomes a particular problem for OEMs as it impacts directly on their service burden and warranty costs due to the need to replace electronic boards and power supplies etc.
Destruction
Destruction can occur when a power disturbance is so large that its energy literally blows up or destroys a semiconductor device like a transistor or integrated circuit. These disturbances tend to be the easiest to identify because they leave visible evidence such as smoke, soot and charred components.
Destructive events are usually easy to identify. Disruption and degradation tends to go under the radar because they are more difficult to see.
High service call-rates - the red flag for power issues
If we asked POWERVAR's customers to identify the sites where they were experiencing power supply issues then, almost certainly, they wouldn't be able to do so. Instead, we ask them to tell us what sites are generating unusually high service-call rates, especially where no fault is found when the service engineer gets there. Because those are the sites that typically have power quality issues.
In many cases, simply installing power conditioning equipment will make these problems go away. There can be a tendency to try and identify the main target sites within a large installed base where it makes most sense to install power conditioning. In reality, the optimum solution is to aim for 100 per cent coverage. That way, any power quality issues are eliminated. So rather than 'chasing ghosts' and eating into warranty costs, the service team can focus on dealing with real problems.
Avoiding the 'million dollar gamble'
High quality power conditioning equipment can be expensive. Although, compared with the ticket-price of the sophisticated equipment it is protecting, the power quality equipment is usually between just 1 to 3 per cent of the total cost. And it really does not make economic sense to skimp on the specification.
Typically, a low specified UPS system will cost $500, while a unit that provides complete protection will cost $1,000. If we consider only a relatively small fleet of 1,000 units deployed a year then the add-on cost ranges from $500,000 to $1 million. However, it is entirely possible that the more expensive unit might help eliminate 1 service call per unit every year. So with the total cost of a service call starting at a conservative $1,000 (including engineer's time and travel), saving $500 on each unit could actually cost over $1 million a year. In effect, skimping on power conditioning represents a 'million dollar gamble'.
Reducing the service burden proves the ROI case
For over 25 years, POWERVAR as a manufacturer of premium power conditioning equipment has been developing an approach, in close co-operation with various industry leading customers, to help businesses quantify the ROI (Return on Investment) when selecting a power protection solution. The objective is to apply real installation and service costs and metrics in a straightforward formula to illustrate the ROI delivered by power quality equipment. That's money saved which can go straight to the bottom line.
A major focus has been understanding the service burden rate, which is the proportion of the price of a product which is allocated to cover on-going maintenance and equipment repairs during the warranty period. In a series of co-operative customer projects, the range of the service burden rate for manufacturers has been found to be between 4 to 8 per cent of the sale price of the equipment or solution. Detailed analysis of the ROI delivered in real-life case studies provides a powerful argument in favour of power conditioning.
Confident smiles for Planmeca
Planmeca operates at the leading edge of the high-tech 2D and 3D dental imaging sector, installing over a thousand units a year in the US market. With dental surgeries investing up to $185,000 in Planmeca systems, users demand high levels of reliability, because any downtime results in both patient frustration and direct loss of income. However, when POWERVAR first spoke to Planmeca in 2008 they were experiencing a significant level of hardware failures.
Further investigation by POWERVAR engineers revealed that the main factor in the failures was the high frequency noise on the 120 V, 12 A power supply. This is a common issue with dental surgeries where large compressors and vacuum systems tend to create noise pollution on their power supply. The hardware failures were not being caused by single, large voltage spikes, which typically cause instant failure, but by power line noise that gradually wears away electronic components. Over time, this degradation results in premature failure as well as interfering with the reliable operation of digital circuits.
Planmeca had recognized the need to ensure continuity of power supply by bundling UPS systems with their units. However a simple UPS does not address the potentially more serious and damaging effects of transient power disturbances that can only be solved by installing power conditioning equipment.
Planmeca started by putting POWERVAR conditioner's in two particular problem sites, as Mike Torres, Planemeca's North American Technical Operations Manager explains: "These were two of our locations that kept changing equipment over and over to the point that it got to be a joke. When these two sites went from serious problems to zero problems, we knew we were on to something really important."
Five years on, Planmeca now incorporates POWERVAR conditioning equipment as an integral element of all its systems deployed in North America. A planned service burden rate of 6 per cent (which is normal for the medical equipment industry) has been reduced by 70 per cent, generating an impressive ROI of 1,148 per cent (see table below for full details).
With hardware failures related to power quality now a thing of the past, Planmeca has been able to extend its warranty period from two years to five years, at no extra cost. Greater reliability - as shown by a 60 per cent reduction in support calls - has translated directly into improved customer satisfaction levels, offering a significant competitive sales advantage that has seen Planmeca sales increasing year on year.
Money in the bank for NCR
NCR is a world leader in systems for businesses, retail and banking. Its ATM business has achieved significant savings in its service burden costs while delivering an impressive 287 percent return on investment from its purchase of POWERVAR power conditioning products.
The hard cost of poor power quality
While ROI figures provide a powerful argument in favour of power conditioning, there are many cases where a system failure can have an almost catastrophic effect on a business that far outweighs the cost of the equipment. For example, just a few hours of lost production at a semiconductor casting facility could result in losses of a million dollars. Equally, failure of an electronic till at a restaurant over a busy holiday period could make the difference between profit and survival.
It is not always the immediate monetary cost that matters. In some medical laboratories, analytical systems need to run sequenced tests without interruption for days, weeks and sometimes months on end. Just one failure could set a drug development program back by many months.
At least in a drug development program there is always the opportunity to start again. Sometimes though there are no 'second chances'. POWERVAR spoke to a leading clinician involved in research related to Alzheimer's disease and they confirmed that often the samples they work with are simply irreplaceable. If the laboratory equipment fails then the data is lost - poor power quality could literally make the difference between life and death.
There is another factor often overlooked in the analytical sector, which is the critical need to protect the reagent revenue stream. For many manufacturers, their business model relies on selling expensive equipment, possibly costing around $0.5 million, at near cost price and then achieving profitability by selling the essential reagents required for the tests. It is not unlike the way in which printer companies sell their printers at very low prices and then charge a premium for the replacement cartridges. Of course, to maintain the revenue, the equipment has to stay in operation. So it makes sense for OEMs to bundle power condition equipment to ensure that power quality issues are eliminated.
Summary
Chris Walsh of POWERVAR says, "Power quality continues to be a significant issue that threatens the profitability and viability of businesses across a wide range of sectors. Investment in high quality power conditioning equipment is a simple way for customers to focus on protecting the process and for manufacturers to take control of their service burden. The case for ROI is well proven, as shown in the examples here. But there are many other hard reasons for specifying high quality power conditioning solutions, especially when system failure is not an option."
It seems like almost every power protection device that's sold today claims to be a power conditioner. But what really makes a power conditioner? The answer to that question depends largely on determining the power quality needs of the electronic load.
A system with a linear type power supply will frequently already have an isolation transformer but may be sensitive to voltage fluctuations. These systems will probably need some type of surge diverter and maybe a voltage regulator, too.
Most modern electronic systems, however, have switched mode power supplies (SMPS). This type of power supply technology is largely immune to changes in power line voltage but in the process of making the power supply smaller, more efficient, and cheaper, the isolation transformer has been eliminated from the design. Systems with a switched mode power supply will require, at a minimum, a surge diverter, a noise filter, and an isolation transformer.
Meanwhile, any system in which data is held, edited, or manipulated in some way in volatile memory may need the protection of a battery backup system or UPS to ensure that data can be saved and the system properly shutdown in the event of a power outage.
POWERVAR originated the concept of The ABCs of Power Conditioning to simplify the process of understanding power protection and to help customers determine which power conditioning elements are parts of the power protection products they are using or evaluating. All of POWERVAR's product model numbers start with one or more of the ABCs. For example, our model ABC201-11 tells you that the product is a power conditioner containing a surge diverter, an isolation transformer, and a noise filter. Our model ABCE600-11contains these same elements in addition to a battery backup - in other words, it's a fully power conditioned uninterruptible source of power. We've always used the ABCs so that customers may clearly see which protection elements are found in the solutions we manufacture.
A demonstration of power quality and potential solutions can be found at: www.powervar.com/userfiles/wp213.pdf
For more information, please contact
Powervar Ltd
Unit 5 Birch
Kembrey Park
Swindon
Wiltshire
SN2 8UU
Tel: +44 (0)1793 553980
Fax: +44 (0)1793 535350
Email: rob.morris@powervar.co.uk
Web: www.powervar.com
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