Features

Eben Owen, UK channel manager for solutions, for Emerson Network explains why UPS protection is an essential safeguard

A CUT TOO FAR?
The general decline in the economy is causing businesses to look very hard at their operating costs. This will apply not only to existing processes and procedures, but also, perhaps more stringently, to the design of new systems. A fresh look may possibly be taken at traditional system components and radical decisions made. Businesses may even contemplate taking a risk. An example of this would be a decision to limit, or even dispense with, power back-up for an infrastructure reliant on electrical equipment. The decision might be based on comparing the cost of providing power back-up with the possible loss caused by a power failure, or on the judgement that power cuts are so unusual that the cost of providing back-up is not justified.

There are, of course, many instances where power back-up is of paramount importance, such as locations where life support or critical business functions rely on electrical equipment. In such instances, decisions will concern the degree and type of back-up cover rather than whether or not it should be provided. However, in less clear cut circumstances, any decision made should have regard to all the circumstances and to all available information.

OFGEM REPORTS
For several years Ofgem (Office of Gas and Electricity Markets) has published an annual Electricity Distribution Quality of Service Report. The information given in the Reports is based on percentages and averages, and it is made very clear that a wide range of local issues affect the performance of individual DNOs (Distribution Network Operators). The measures of Quality of Service chiefly concern the number and duration of supply interruptions per year. The Report for 2007/2008 showed, across all DNOs, the average number of customer interruptions, or power cuts, during the year was approximately 70 per 100 customers and that the average minutes lost throughout the year was approximately 65 minutes per customer.

The Report also points out there were a number of short interruptions, being planned power cuts lasting less than three minutes that are brought about by operations of the DNOs, designed to reduce the length of interruptions, the majority being associated with automatic restoration schemes. The average number of short interruptions per 100 connected customers was 86.

In addition to these broad indicators that random interruptions in service apply in every DNO, at an historically fairly consistent level, the Report also shows the average duration of those interruptions. It appears that almost 60% of interruptions in 2007/08 were restored within one hour, whilst some 25% of inerruptions lasted between one and two hours.

RISK ASSESSMENT
It is against this background decisions regarding power back-up must be made. Power failures will happen, which in some 80% of cases have the potential of lasting for between three minutes and two hours. An interruption can, of course, happen at any time on any day and could quite easily occur when the electrical equipment is, in any event, switched off. However, unless the random interruption of power to electrical equipment that is actually in operation is of no consequence, the risk associated with any power interruption must be carefully assessed.The type and extent of the appropriate back-up will be determined by the level of sophistication and the practical function of the equipment itself. One possibility is full continuous activity is required for a specific limited number of hours each day, with the balance being a period at a lower level, perhaps over night. Another location may best be served by a back-up facility that enables ordered equipment and system shut down in the event of power disruption, whilst another, as a business-critical undertaking, will require a facility that provides ongoing, continuous operation until utility power is restored.

Although the Ofgem Report presents the overall average picture of the potential risk of complete power failure, any decision regarding power back-up will also need to take into account  the unquantifiable number of occasions when the power supply will be distorted by potentially harmful sags, spikes and other irregularities.

A PROVEN SOLUTION
UPS is one well known protection for electrical equipment against aberrations in the utility power supply. Different UPS topologies provide a range of options, from basic battery back-up as an energy substitute during periods of power irregularity through to sophisticated power conditioning functionality that constantly replaces utility power. Depending on the level of availability required, the UPS solution could be a parallel redundant system, a hot standby system or a dual bus system.

Identifying the actual risk to both electrical equipment and systems of irregularities or failures in the power supply and sizing the appropriate solution is not simple. For this reason leading manufacturers and equipment providers in the industry supply extensive product information. This is most commonly available as printed literature and on providers' websites, complemented in some instances by one-to-one on call technical advice.

THE RIGHT ANSWER
The great majority of businesses, however small or large and wherever situated, as well as many individuals, are likely to be reliant on electricity to power their activities. That fully guaranteed utility power cannot be provided, in terms of both availability and quality, is an established fact. Consequently, UPS back-up solutions will be an important consideration when systems and processes that rely on electrical equipment are being designed. Companies like Emerson Network Power provide a wide range of information and advice to enable the right type and degree of UPS cover to be identified and selected for every type of location.

A tailored and integrated approach to power protection, comprising modular UPS and   fully-matched standby generators, is helping businesses sustain vital uptime and availability, explains Alan Luscombe of Uninterruptible Power Supplies (UPSL)

Changes in the business landscape, the growing risk of nationwide power cuts, and advances in technology are accelerating the uptake of more flexible and efficient UPS systems. 

With global 24/7 online trading and customer expectations of immediate, anytime availability, power continuity around-the-clock is often essential: in highly competitive markets even a minor interruption to business systems can cause considerable revenue losses.

Whether due to planned maintenance or unplanned power outages, system downtime is undesirable - and increasingly unacceptable for business critical loads. The UK's ageing power stations and unproven alternatives are a major cause for concern and should spur organisations to urgently review and reinforce their power protection systems, to ensure they can cope with unreliable supply, more frequent interruptions, and the possibility of long term power cuts.

Design for uptime
Transformerless three-phase UPS technology, introduced in the early 1990s and now widely adopted, delivered significant weight and space savings and enabled the development of rack-mounted modular UPS systems.  Compared with traditional free-standing units, these units can reduced the required floor space by 75%, and vertically scalable modules mean that additional capacity for redundancy or load upgrades can be easily achieved at a fraction of the cost of adding an additional stand-alone unit.

Going back just a decade, only 10% of three-phase UPSs were parallel redundant systems but today this configuration accounts for more than 70% of installations. The majority of organisations needing protection for critical loads are upgrading to parallel redundancy, providing a minimum of one UPS over and above that required for capacity and ensuring continuous support of the load if any one UPS shuts down.

When specifying a UPS system, it can be difficult to predict what the power requirement is going to be so installations are often over-sized to provide contingency, creating a wasteful gap between installed capacity and the size of the actual critical load. While this may ensure sufficient UPS capacity, it means inefficient operation, additional expense and inefficient use of energy and costly floor space.

However, rack-mounted modular UPS configurations can be cost-effectively ‘right-sized' from outset more easily by inserting or removing ‘hot-swappable' modules, enabling power to be added as requirements grow without downtime or increasing footprint. Hot-swap technology, along with significant reductions in repair time, can also achieve six nines availability (99.9999%) - highly desirable in the pursuit of zero downtime.

Modularity improves efficiency by working closer to the load capacity than traditional UPSs but without sacrificing the security of the system. The more a load approaches the capacity of any UPS, the more efficiently the UPS operates. A traditional stand-alone parallel redundant system is typically just 50% loaded while a modular solution typically achieves a 70% or higher loading. This reduces energy use, Co2 emissions and UPS cooling requirements.

Cost benefits
The scalability of modular systems contributes major savings. Compare a single stand-alone non-redundant 100kVA UPS solution with a parallel redundant 3 x 50kVA UPS modular solution. While the latter may carry a price premium, the cost-benefit is quickly apparent. The modular configuration provides redundancy if one of the units fails, and modules can be added to accommodate an increase in capacity, in affordable, incremental steps without interruption to the critical load. The stand-alone system provides no redundancy and the addition of a second parallel 100kVA unit to increase capacity would be more costly, take up twice the space, and would also incur downtime during installation.

Price sensitivity is understandable, especially in the current market where expenditure on capital equipment may be subject to tougher scrutiny. However, while the purchase price of a traditional standalone UPS system can be typically 10% to 15% less than an advanced modular UPS system, total cost of ownership should be considered. The lower purchase price of traditional standalone UPS technology must be offset against significantly higher operating expenses in comparison with a modular system based on technology which reduces energy loss costs.  In fact the higher initial price of the modular system can be recovered within the first year of operation, and a comparison of additional long-term costs also favours modular technology.

For example, approximately £150,000 could be saved over five years by replacing a ten year old 400kVA parallel redundant UPS system, running at half of its rated capacity, with a new decentralised parallel architecture (DPA) 200kVA parallel redundant UPS system. This would also reduce CO2 emissions by over 700 tonnes and cut floor space by 70%.

Upgrading a traditional UPS demands extra space, costly cabling and potentially involves taking the UPS system off-line during the upgrade. With a modular UPS, the upgrade is performed by simply inserting the additional power modules into the rack, without any interruption to the load, without increasing the footprint, and with no additional work on site. This flexibility makes upgrading a system very easy, and with little additional cost.

Standby power
There may be situations where organisations can tolerate occasional downtime, and in this case a UPS fitted with a standard or extended autonomy battery may provide the required system integrity. However, where downtime is untenable, a standby generator with automatic mains failure (AMF) detection and changeover facilities will be a vital part of the protected power supply system. 

During a mains supply failure, the UPS battery will support the load for the time it takes the generator to start, stabilise and be switched over to supply the UPS. Assuming the generator has been correctly sized for the application, the UPS will accept the generator as a ‘mains replacement', start to recharge the battery and continue to supply the critical load for the duration of the interruption.

Round-the-clock dependence on uninterrupted critical loads means that this seamless interaction between UPS and standby generators is an important requirement. Turnkey supply and installation also delivers valuable integration benefits, ensuring fully matched UPS and generator systems, removing the problem of demarcation between different suppliers and eliminating potential points of failure. Individually sourced units can compromise system autonomy and presents a risk of mis-sizing, causing installation and commissioning problems. A packaged solution with fully matched UPS and standby generator ensures a true ‘no-break' supply in the event of a mains failure - protecting critical loads and assuring uptime.

Ever increasing demands from large customers to reduce the cost of Capital Projects  must inevitably affect the reliability of the equipment supplied unless new ways are established to determine value for money. Iain Campbell, Industrial Director UK & Ireland for AEG Power Systems, proposes a wider look at the lifetime cost of ownership of mission critical UPS systems as an alternative to simply ‘reducing the bottom line'

Large industrial projects are being restructured in response to the current global downturn, falling oil and gas revenues and increasing operating costs. New projects are seeking ever lower equipment costs to minimise capital expenditure. While large organisations have some control over their own overheads there is a drive to reduce the cost of materials and services they buy and an expectation that their suppliers will respond to these demands. Failure to respond may well put existing and future business in jeopardy with work being deferred or cancelled.

Active cost management is seen as a key step required to maintain this kind of business relationship but does this necessarily mean reducing prices to the point that performance must suffer? Significant emphasis must now be placed on making every euro or pound spent as effective as possible and also ensuring that each supplier involved in a potential project contribute in a positive way to managing costs.

AEG Power Solutions, is an approved supplier to key industries worldwide, including oil and gas, power generation and transmission, transportation and the manufacturing industry, and has received several requests to propose positive solutions to reducing key project costs. From a purely financial perspective it would seem simple to reduce costs by reducing manufacturing labour or material content and passing any savings on to the end customer. In reality the very nature of the ‘mission critical' UPS products and services provided to customers means such cost reduction must not be allowed to compromise the reliability and operational compliance required, limiting this as a viable option.

In common with most major electronics manufacturers AEG employ state of the art designs and manufacturing facilities to ensure highly cost effective manufacturing processes delivering reliable products. AEG designs feature ‘designed-in redundancy' and have minimised the numbers of system elements, rectifier, static bypass and inverter. This not only improves reliability but simplifies service, reduces any potential downtime and overcomes any potential component obsolescence over the lifetime of the UPS.

If the product design and manufacturing processes are already at optimum price-competitiveness, how then to respond to the continuing calls for cost efficiencies? AEG's solution is to provide a complete project management infrastructure to engage with the client at the earliest stage of a new project and create a solution that fully meets the customer's requirements. This ensures the elimination of any wasteful over-specification that will not add to the overall system function or reliability. Further overall cost reductions may be achieved by early consideration of installation scheduling, future service requirements and agreeing on a realistic documentation package which can be produced and distributed electronically, eliminating expensive hard copies, saving many hours of correspondence and producing documentation that adds little or no operational benefit to the customer.

From its foundation in 1887, AEG has pioneered advanced electrical engineering. Today's UPS solutions major on providing technical solutions that deliver significant savings on total lifetime costs by considering all aspects of any initial proposal that have an impact on the total cost to the customer when providing a standby power solution for critical loads.

With a portfolio of AC and DC power solutions up to 8MVA, remote monitoring options for all standard operating systems or custom software if required, AEG aims to deliver commercial UPS systems on short lead times and offer rental of UPS systems for short-term projects or while power infrastructure is being replaced or upgraded.

WEB EXCLUSIVE Under the new European Machinery Directive 2006/42/EC either of two standards can be followed to demonstrate sufficient reliability of the control system; BS EN ISO 13849-1 or BS EN 62061 and these introduce the notion of not only if, but how likely, faults are to occur.  This means there is a probabilistic element in compliance that must be quantified and to do so panel builders must be able to determine levels of safety integrity or performance. Therefore there is increased onus on manufacturers to provide safety relevant data for their products, but understanding the information given can be a minefield. Peter Still, Schneider Electric's standards manager, provides panel builders with the essential information they need

From 29 December 2009 the European Machinery Directive 2006/42/EC supersedes the Machinery Directive 98/37/EC and in the UK, the Supply of Machinery (safety) Regulations 1992 as amended will be replaced by the Supply of Machinery (safety) Regulations 2008. 

The new Machinery Directive, like other new approach directives, does not demand the use of any standards. However, the simplest way for a designer to demonstrate that he has met the relevant requirements of the Directive is to comply with one or more harmonised European Standards that can give a presumption of conformity to those requirements.

One of the main changes relevant to the new Machinery Directive relates to the standards used when designing a safety related electrical control system (SRECS) to be fully compliant. Panel builders who currently use BS EN 954-1 to design safety related parts of electrical control circuits will be familiar with the ‘risk graph'. Here, severity of injury, frequency of exposure and possibility of avoidance are subjectively assessed, to arrive at a required category (B, 1, 2, 3 or 4) for each safety related part. This category then stipulated how the safety circuit must behave under fault conditions.

However, with modern systems more commonly incorporating electronics and programmable electronics, the categories are insufficient to define the performance of the safety-related parts, so a standard is required to provide information on the probability of failure - it is no longer a case of if faults are going to occur, but how likely it is. In addition, the safety functions needed by modern machines are too complex to be addressed simply by considering the behaviour of the individual components; it is necessary to consider the overall safety functions provided by the control system.

As a result, the new standards BS EN ISO 13849-1 and BS EN 62061 have been designed to address the weaknesses of the old BS EN 954-1. Either of these standards can be followed to comply with the relevant essential health and safety requirements of the Directive. The performance of each safety function is then specified as either a performance level (PL a, b, c, d or e) in the case of BS EN ISO 13849-1 or safety integrity level (SIL 1, 2 or 3) in the case of BS EN 62061. 

Although the circuit architecture is still a major consideration within them, these standards also take into account the reliability of the safety circuit components and their ability to detect/diagnose faults and prevent common cause failures. Therefore, to verify their safety circuits meet with the determined PL or SIL, panel builders must be now able to determine the integrity of the components used within them.

To assist panel builders in doing so, manufacturers should make the safety data relating to their components, including detection devices, logic solvers such as safety PLCs and output devices such as contactors, completely visible and panel builders should use this data to specify products.

However, the data relating to components can be complicated and there are some terms vital to compliance. Only when these are fully understood can panel builders meet either BS EN ISO 13849-1 or BS EN 62061.

There are four main terms that need to be understood to comply with BS EN ISO 13849-1, these are; mean time to dangerous failure (MTTFd), diagnostic coverage (DC), performance level (PL) and common cause failures (CCFs).

MTTFd (mean time to dangerous failure) is the average period before the failure of a component used in the safety circuit can prevent a safety function from being performed. There are three classifications given to products; high (low risk, 30-100 years), medium (10-30 years) or low (high risk, 3-10 years) however, it's important to remember, if the component's MTTFd is 100 years it does not mean it will last this long without fault. This information is important because staff can be at risk if the product fails, so manufacturers of electronic safety devices (such as safety relays, safety controllers and safety PLCs) must make this data available to panel builders.
However, MTTFd is only an estimate of the likelihood that product may fail, so a control system should also be able to detect/diagnose a fault within itself (e.g. short circuit) to prevent a dangerous failure of the safety function. This is known as DC (diagnostic coverage) and the higher the level of automatic diagnostic tests, the lower the probability of hazardous system failures. Typically, safety devices like safety relays and contactors with mirror contacts can be used in systems with high DC.

Together, the circuit's MTTFd, DC ratings and circuit architecture (category B, 1, 2, 3 or 4) as in BS EN 954-1, can be used to define a PL (Performance Level) for the system. This is a discrete level, which specifies the safety-related control system's capability of the performing a safety function under foreseeable conditions and is rated from a to e. PLa represents the lowest and PLe represents the highest probability of performing the function. If a manufacturer states a specific PL for a component (such as a safety relay) it means only this is the highest PL a circuit incorporating that component can achieve. The important thing to remember here is that the PL applies ultimately to the channels and the whole safety circuit, not to each individual component.
Common cause failures (CCFs) also need to be considered. These are defined as ‘failures of different items, resulting from a single event, where these failures are not consequences of each other'. For example if two identical components are operated at the same time in the same way, then the chances of both failing at the same time are higher than if they were driven differently or if they were of different design. Steps can be taken to prevent common cause failures, such as using different types of components in dual channel systems and driving them in different modes, and guidance is given in the standards.

For compliance with BS EN 62061 there are slightly different terms that are vital to compliance, including safety integrity level (SIL), SIL claim limit (SILCL), probability of dangerous failure per Hour (PFHD) and safe failure fraction (SFF).

SIL (safety integrity level) is a discrete level used to determine the safety integrity requirements of the safety-related control system. These levels range from one to three; one is low and three is high. The risk assessment can be used to assign a target SIL to each safety-related function. As with the PL rating in BS EN ISO 13849-1, if a manufacturer states a specific SIL for a component (such as a safety PLC) it means only that this is the highest SIL which a function performed by that component could achieve. 

This target SIL is then used to determine the SILCL (SIL claim limit) that is needed for each of the subsystems within a safety system. A subsystem is defined as a part of a safety system/circuit, which, if it fails, will bring about a failure of the whole safety system/circuit and SILCL is the maximum SIL that can be claimed for a subsystem in relation to its architectural constraints and systematic safety integrity. 

To establish the SIL, the reliability of the entire safety system/circuit needs to be identified. In much the same way as MTTFd is in BS EN ISO 13849-1, PFHD (probability of dangerous failure per hour) is a measure of the probability of failure, which could result in failure to perform a safety function, so manufacturers of electronic safety devices (such as safety relays, safety controllers and safety PLCs) should make this figure available. 

However, dangerous failures are not the only failures that need to be considered. Manufacturers can choose to give panel builders information about the share of failures within the total rate of failure that does not lead to danger and this is known as SFF (safe failure fraction). However, what defines a safe failure is application-specific; for example, a contactor sticking closed on a motor driven saw is obviously dangerous, as it means the saw will not stop if the contactor is de-energised, but in a cooling system, failure to stop the cooling pump is not usually dangerous.  Manufacturers can therefore find this difficult to establish without knowing how the component is going to be used.

The MTTFD and PFHD are both time-dependent estimates of reliability, and are not really applicable to electromechanical components, for which the probability of failure is related to the number of operating cycles. Because of this, for both BS EN ISO 13849-1 and BS EN 62061 it is necessary to know the B10 and B10d figures for the circuit's electromechanical components. B10 is the number of operations at which 10% of the ‘population' of a component will have failed and B10d is the number of cycles after which 10% of the population will have failed to a dangerous state.  Since the frequency of operations is application specific, electromechanical components do not have published MTTFd or PDHD figures, so panel builders can use B10 or B10d with known machine data to calculate MTTFd or PFHD of subsystems containing these components.
Understanding all of this data relating to safety components can be confusing and because some of the data is application specific, calculating failure rates for the safety circuit will require safety related knowledge. To overcome this, panel builders should look at partnering with a manufacturer to ensure their systems and subsystems comply with all relevant standards. They should select one that can confidently offer data on all safety related components.  For example, Schneider Electric has a wide range of knowledge and understanding of panels and systems, thanks to a broad product offering and experience of working with panel builders to design and create entire processes. Because all of the products are manufactured by the company itself, there is full assurance they meet all relevant safety standards and data is accurate and visible.
To help panel builders further Schneider Electric has also devised a Safe Machines Handbook, an unbiased and concise guide explaining the new directive, which can be downloaded by visiting: http://.schneider-electric.co.uk.

WEB EXCLUSIVE In this special feature Jeremy Hodge, Chief Executive of Basec,  explains all there is to know about the organisation, and why he believes BASEC approved cabling is a must for the electrical sector

The British Approvals Service for Cables (Basec) is a recognised sign of assurance of independent cable testing and approval. A non-profit making Government-nominated body, Basec has for more than 30 years been a mark of reassurance to those specifying cable. 

A leader in product certification services for electrical cables, data and signal cables and ancillary products, Basec has a reputation for quality, clarity and ensuring safety in cables.
All products are rigorously tested to meet necessary and appropriate British, European and international standards through detailed examination of manufacturers' production processes and controls, and regular product testing.

As outlined below, Basec offers a range of services in product approvals and certification, systems assessment and certification, auditing for process capability in cable making and independent testing and reporting in the event of disputes:
- Product approvals - manufacturers submit each cable type put forward for Basec approval for a full range of tests to check the products comply with national and international standards.  Only after Basec has also verified that a cable manufacturer has the facilities, processes and the capability to make good cable is a license awarded, permitting the manufacturer to display the Basec mark on their products. Each approved cable is then regularly retested by Basec to ensure ongoing conformity.
- Systems assessment and certification - here Basec operates individual or integrated management system assessment schemes, leading to the company issuing management systems certification. The Basec schemes are designed to assess an organisation's general ability to produce goods and services consistently to specification and customer requirements, in a safe manner and with due regard to environmental needs.
They include:- 
- Quality management systems to ISO 9001
- Environmental management systems to ISO 14001
- Health & Safety management systems to OHSAS 18001
Audits where more than one of these is employed may be conducted individually or on an integrated basis.
- Certificate of Assessed Design - Basec offers a Certificate of Assessed Design for new concepts where no national or international standard yet exists. In this instance a manufacturer's or user's/other specification may be used as the baseline specification, which Basec may review to ensure that current industry requirements, e.g. particular test methods, are incorporated as appropriate.
- Independent testing and reporting in the event of disputes - this enables an interested party to have a cable independently tested. This service allows reports to be issued regarding a cable and its conformity to a specification, but no right to use a Basec mark is awarded. Forensic investigation can often assist in cases of cable failure or for product selection.

Basec approves to many national and international cable standards
Basec offers product approval to a wide variety of cable standards, and also offers bespoke approvals for products where standards do not yet exist. 

The main group of standards are British cable standards. These include BS 6004, BS 6231, BS 6500, BS 7211, BS 5467, BS 6724, BS 6622, BS 7629-1, BS 5839-1 and many others.
Basec also offers approval to European (Cenelec, harmonized) standards, to international (IEC) standards, and to sector standards (e.g. TIA). It can also approve to other national standards, such as Irish, Malaysian, etc.  Basec is a member of the HAR scheme for harmonized cables made in Europe.

All approvals follow the same approach. Each approved product is subject to a high level of product testing, manufacturing assessment and ongoing surveillance, in accordance with Basec's scheme rules and regulations.

Who tests the cables?
Basec employs a number of laboratories to conduct testing of cables, to ensure the products sent to us undergo fully independent test procedures using the latest equipment and technology.

In support of this, the assessors make visits to clients and prospective clients' manufacturing plants to monitor the whole process. Only by checking processes at first hand can we ensure that systems are inherently reaching relevant standards.

It is also possible for assessors to witness testing at manufacturers' premises where suitable facilities are available.

The assessors are highly skilled, experienced engineers and auditors who possess extensive in-depth commercial and industrial knowledge. They have a reputation for being highly professional and rigorous and are responsible for approving Basec's highly respected certification. They need to be fully aware of the latest standards and test criteria and what they mean in the UK, across Europe and worldwide.

Only cable marked with the Basec name is Basec approved
It is a common misunderstanding that a cable is compliant with standards or even Basec approved just because the supplier claims it has been produced to a particular standard. Cable marked with only a standard number should be treated with caution. It is probable that nobody independent of the manufacturer has examined that cable, and the claims made may be unreliable. Only cable marked with the Basec name is Basec approved, by demonstrating its compliance to the required standards.

Cable standards not only specify the dimensions and materials of a cable, they also require that a range of specific tests are undertaken to prove the construction and performance. Many non-approved cables have not been subject to the required tests.

What's the difference between Basec and BSI?
The British Standards Institution (BSI) is the body which co-ordinates the writing of standards for cables and other electrical and electronic systems in the UK. Basec works closely with BSI's cable committees in the development of standards. For example, it is responsible for drawing up a standard for a specific reason, say to ensure a cable meets certain fire performance criteria and how it needs to perform in the event of a real fire. Assessors from Basec will then ensure the cables which manufacturers would like to be approved as meeting that standard do, in fact, achieve the standards' criteria through testing the product and the manufacturing process.

WEB EXCLUSIVE Traditionally, when it has come to exterior lighting, less energy- efficient lamps have remained the predominant choice due to their low price. However, as the issue of sustainability continues to dominate modern life and with further EU legislation surrounding low efficiency lamps set to come into force this September, contractors need to take action now when specifying exterior lighting and make the switch to greener technologies. Here, Steve Havell, product marketing manager at electrical distributor Newey & Eyre, discusses the latest lighting solutions available for outdoor applications

Exterior lighting continues to enjoy a boom.  In today's ever safety-conscious world, illumination of both public and private spaces is becoming increasingly important as a way to heighten security. More specifically in the domestic setting, there is an increased focus on the garden as an additional living space, leading to further demand for exterior lighting solutions as a means of improving the outside environment and creating extra room.

The multi-million pound preparations around the 2012 London Olympic Games are also likely to have a major impact on demand for exterior lighting. Under plans to prepare for the Games, the government is committed to raising the nation's international profile as a visitor destination and develop sport in the UK. This will involve an investment in facilities and structures to meet growing needs, from sports centres to businesses involved in the hospitality trade, all of which will cause a greater demand for exterior lighting in the supply chain.

Looking ahead, the exterior lighting offering to meet this growing demand is set to change dramatically over coming years.  As the European Union plans to phase out many traditionally used tungsten lamps in steps starting from September, in a bid to slash carbon emissions and promote sustainability, it is important for contractors to be aware of emerging technologies and understand their benefits. This will allow them to offer up-to-date products and advice.

Making it easier for contractors to do this, manufacturers have dedicated significant resources over recent years to research and develop new energy efficient products. However, despite the associated problems with traditional solutions, such as inefficiency and low life expectancy in the tungsten halogen lamps and poor colour rendering of SON lamps, these options have remained the predominant choice with contractors.

In a bid to resolve all related issues with traditional options, the new metal halide lamps coupled with corresponding fittings offer an effective, sustainable solution. Originally created for industrial use but increasingly used in the commercial sphere, these lamps produce light by passing an electric arc through a special mixture of gases under controlled pressures and temperatures.

Producing a distinct white light with high colour rendering capability, metal halide is suitable for outdoor lighting in commercial and domestic areas, in particular those where security systems are used. Helping to meet the ever-growing need to sustain our environment through the use of more energy-efficient and durable solutions, these lamps also deliver high-efficiency and an average life expectancy of up to 12,000 hours plus.

LEDs are also making their presence felt in outdoor lighting.  Looking to the immediate future, improvements are being made in LEDs to make them brighter and more suitable for all types of applications, particularly outdoors. Further benefits include a lifespan of anywhere between 30,000 up to 100,000 hours, high reliability and minimal maintenance requirements, making LEDs ideal for use in all types of outdoor applications.

In particular, LED solutions are becoming the obvious choice for outdoor applications which require aesthetic elements.  This is due to the fact that they can be controlled digitally, offering the ability to produce millions of colours and colour-changing effects at the push of a button. This makes them ideal for use in decorative lighting schemes for arenas and outdoor venues for concerts, sports events, and other gatherings.

As one might expect, the additional benefits offered by both of these lamps can result in higher prices which may act as a deterrent for contractors inclined to favour the cheapest option as a means to offer the most competitive quote. However, looking deeper than the initial investment, it can pay dividends for contractors who take the time to enlighten their customers to the many benefits attached to using this newer technology, installing the most effective solution and maximising profit potential.

In terms of energy for example, the first point to remember about the majority of the more advanced energy efficient options, such as metal halide lamps and LEDs, is that it's not just about the output of these products but increasingly about the longevity and overall lifecycle costs. While a tungsten halogen lamp may offer a quick and affordable fix in the short-term, it actually makes more financial sense to switch to more efficient solutions as they require less maintenance and also incur lower energy bills, making it a more appealing option for them to pay a little bit extra. 

As the issue of sustainability continues to dominate all aspects of modern life, the exterior lighting sector will adapt according.  This is why it is important for contractors to look to the future needs of the customer and the project as a whole. They must select not only a light source that meets the requirements of the application but should ensure an energy efficient installation that will be sustainable for years to come.

Although, times as they are, it is understandable that cost can be a major factor, the future focus will be on efficiency and longevity. The exterior lighting market is expected to see significant growth over the next few years and, in order to take full advantage of the opportunities this presents, contractors need to look at the bigger, long-term picture. Rather than automatically favouring the low-cost option, it is important to give customers the choice of the latest technologies, before they eventually go to someone who will.  As well as enjoying the additional profit this will bring, contractors can rest assured that they have helped customers to reduce their energy bills and maintenance requirements, in the long term this more than offsets the initial cost. 

WEB EXCLUSIVE Before embarking on this month's rant, let me state I am not in favour of the nanny state.  I object to traffic calming measures, other than around schools and hospitals; I find it facile that ofcom demands that TV shows can only depict car thieves if they're shown driving off wearing their seatbelts; and I don't think playground conkers is a blood sport!

However, while to the best of my knowledge there have been few, if any, conker related fatalities I have been drawn to a statistic that is frankly alarming. About ten people a day in the UK suffer severe injuries, or worse, as a result of electrical crossovers - I still prefer the term arc flash. This figure is appalling, but may not even be accurate since that estimate is drawn only from victims reporting to major burns units. How many more minor injuries and near misses go unreported is anybody's guess.

I know that some jobs are hazardous. Miners, construction workers, civil engineers, oil and gas riggers all carry risks that are well known to those employed in those industries. Of course electrical engineers also work within high risks, but these risks are largely predictable and with due care, attention and training the dangers can be militated for. Not so in the case of arc flash it seems.

While most Review readers are aware of arc flash, it's worth highlighting the nature of this hazard. Typically arc flash temperatures reach 3,000oC but in large equipment they can reach nearly 20,000oC - and that's four times hotter than the surface of the sun! In such extremes injuries can be caused up to 10m from the flash. At the same time, super heated gases burn the throat, lungs and other internal organs. Such is the acceleration of the ionised air that fiery plasma erupts as a fireball. Metals in the immediate vicinity are vapourised (and breathed in), while other more distant metal objects may be blasted into high speed shrapnel. Injuries can be horrific and fatalities can be long and painful. Coupled with the unpredictability of arc flash incidences, some electrical engineers are working in the industrial equivalent of minefields.

Now, the problem seems to lie in the relative looseness of regulations covering those working in the potentially hazardous areas where arc flash can occur. Regulation 14 of the Electricity at Work Regulations 1989 makes clear (sic) three conditions that must be met for live working to be permitted. These conditions are: it is unreasonable in all the circumstances for the conductor to be dead; it is reasonable in all the circumstances for that person to be at work on or near that conductor while it is live; suitable precautions (including where necessary, the provision of personal protective equipment) have been taken to prevent injury. It strikes me I could dream up any number of reasons compliant with the Regulations.
Don't get me wrong, I fully appreciate in the real world risks are sometimes unavoidable. My concern is what constitutes a reasonable and acceptable risk is not defined at all!
Naturally manufacturers whose equipment is most subject to potential arc flash - such as switchgear makers - are often reluctant to discuss the risks. However, this surprises me since the best of them now have remedies built into their latest equipment. The UK's biggest switchgear manufacturer claims to have a really innovative arc quenching solution using volcanic rock, but when I asked to write about it I was forbidden from doing so. This suggests to me that either the system isn't 100% reliable or that the company believes that by flagging up the risk it might jeopardise sales.

One would imagine if working practice legislation doesn't work - remember there are ten casualties a day - it would be relatively straightforward to at least regulate the specifications of all new equipment. Surely, if equipment makers have suitable arc suppressors, they would welcome and lobby for such a move.

I struggle to think of any walk of life in Britain, where 3000 extremely serious casualties a year fail to bring about preventative or at least protective government action. It seems we worry more about the welfare of our conker players more than we do the electrical engineers that keep our business, industry, commerce and infrastructure running.

John Houston can be contacted on 01797 364366 or by e-mail at This email address is being protected from spambots. You need JavaScript enabled to view it.

The UK is now fully immersed in the implementation of the Batteries Directive and, in December, the Government outlined its proposals in the final consultation document for how the directive will work in the UK. Its proposals left those obligated by the new legislation concerned that, without further thought and modification, the UK will not hit the stringent collection and recycling targets expected of it. Here Vince Armitage, divisional vice-president, Varta Consumer Batteries UK gives a brief overview of where the directive currently stands, how it will affect retailers in its current form and suggests areas for improvement.

The Government completed its final consultation on the legislation in December 2008, a process which caused great concern amongst producers, retailers and wholesalers. While there are many facets to the directive and many areas of concern, I shall try to briefly outline the main points.

The Government proposes the Batteries Directive is served by a network of competing compliance schemes, much in the same format as the WEEE Directive. This is something that goes against the wishes of the industry which believes that either one single scheme or a small number of schemes with an umbrella co-ordinating body is the way forward. When it comes to collection, the Government will allow the individual compliance schemes to specify their collection network and are unlikely to fund a comprehensive sustained national publicity campaign around the directive, leaving communication with the end-user primarily to the producers and the compliance schemes.

The news the directive will be monitored and enforced in the UK by the Environment Agency, funded by producers to the tune of £650,000, has left many in the industry concerned given poor awareness of the WEEE Directive. This concern is further compounded by the fact that in the current plans laid out by the Government, there is very little transparency which shows how the money generated is being used.

Cost of compliance is another area of contention. As it stands, all obligated producers will have to sign up to a compliance scheme but, if the producer places less than three tonnes of batteries on the market per year, then they will be exempt from paying towards the cost of collection. However, closer examination of the figures shows that the current threshold is set too low, meaning that out of 1,000 obligated producers, only 50 to 100 could be liable to pay any compliance scheme membership costs. The remaining small group of obligated producers could then face significant additional financial burdens in order to offset the non-obligated producers.

This also presents questions around the differences in size between the obligated producers. Currently, producers that place more than three tonnes on the market per year, regardless of its precise tonnage or turnover figure, will have to pay to fund compliance. Therefore, an organisation that barely scrapes above the threshold will have to pay the same amount as a producer that places ten times as much on the market and has a significantly higher turnover. All of this added cost will have knock-on effects for everyone in the batteries supply chain, with one of the main consequences being a rise in the cost of batteries.

The knock on effect for retailers
With this added financial levy on producers, it stands to reason that, with the mounting cost of compliance for manufacturers and producers, many in the industry will look to recoup this cost through raising unit prices. As a result, retailers and wholesalers will see their margins squeezed as prices rise. To make-up the shortfall, wholesalers will be faced with having to raise their own prices to the buyer which will not only affect sales but will also have a detrimental effect on the success of the Batteries Directive.

The reason being is that the end-user will look towards cheaper alternatives. In the battery sector this will mean cheaper, lower quality Far Eastern imported batteries. This defeats the purpose of the directive on two fronts. Firstly, those batteries will be poorly constructed which reduces their performance. In today's power hungry devices, it will mean that users will use more batteries to get the performance they require. This in turn will lead to more battery waste.

While we are looking to change the buying habits of end-users to consider the environment, we may actually be changing their buying habits for the worst. Due to the current economic situation, cost is a big factor and therefore, increased batteries prices driven by the directive may create a mindset of cost before quality which, when the credit crunch ends, may be hard to reverse by all parties in the supply chain.

The problem is further compounded due to the materials used to construct the casing of these batteries and the materials used inside. As the casing will not be as strong as those batteries which conform to the more stringent European Standards, these could cause even more environmental damage, nullifying the point of the directive.

The fact the batteries are imported and often sold through market stalls or discount shops will also reduce the impact on the success of the directive. It is fair to assume that many of these retailers will not play an active role in ensuring that their buyers know about the directive and will not ensure dead units are collected and recycled. Also, as a lot of producers will be smaller manufacturers from the Far East, many will look to avoid any kind of contribution to the cost of compliance and the majority will not have the volume needed to become liable for the cost of compliance.

Indeed, the collection of batteries is an area that still has to be resolved. In its consultation document, the Government has left it to individual compliance schemes to structure their own collection networks, which could mean compliance schemes may focus on the areas that offer the greatest volume of returned batteries, such as large urban areas, while remote and sparsely populated areas will be neglected. This will reduce efforts to hit the targets laid out in the directive. A better solution would be to follow the lead of other European countries and utilise the high footfall locations that consumers visit on a daily basis.

Across Europe, collection points are centralised in retail outlets, post offices, supermarkets, petrol stations and even schools. This means little effort on the part of the consumer but also driving footfall to retailers, encouraging the replacement of like for like product.
 
Shouting about it
While the debates around cost, collection and compliance are important, if the aims of the directive are not communicated properly then it will simply fail. In spite of the criticism around the poor publicity of the WEEE Directive, it seems the Government is set to make the same mistakes again as it has not clearly stated that it will fund an ongoing national publicity campaign to educate the end-user about the directive.

The problem will be made all the more difficult due to the proposed multiple compliance scheme structure. Multiple schemes will mean a dilution of the messages that reach the end-user. Each compliance scheme will have its own smaller PR and marketing campaigns, which will ultimately compete against each other for air time and column inches. As a result, the messages will reach a smaller cross-section of people and will not have the same impact as one universal campaign.

A Government-supported campaign would mean that a strong and consistent voice is heard by the target audience. By pooling resources, a more impactful national campaign could be run, increasing awareness and driving success. National messages could then be broken down and shared at a regional and local level - ensuring more and more people are exposed to the directives and its aims.

It must be remembered any directive will have an effect on everyone in the sector from producers to retailer to end-user. Careful consideration needs to be given so as little disruption as possible to the norm is caused. 

The support and enthusiasm of retailers and wholesalers will play a large part in the success of the directive. Any legislation must embrace them, bring opportunity not restrict it and channel their energies to make sure the new legislation is as successful in the UK as it is in other European countries.

Hydraulic systems waste much of their energy as the fluid circulates at a constant  pressure, regardless of the amount of work carried out. Despite this, drives are not widely used in hydraulic installations, perhaps because the very impressive savings normally achievable in standard pump applications are not possible with the type of pump used in hydraulics. However, when Corus Colors on Deeside looked closely at the issue, the company found significant energy savings could be achieved

When an ABB industrial drive was installed on a hydraulic pump, steel manufacturer Corus Colors on Deeside recorded a 70% energy saving.

A trial was carried out by a graduate engineer at the company, Rob Chew, and Phil Tomkinson of Radway Control Systems. The aim of the study was to establish whether the drive would be a viable option for controlling energy consumption in hydraulic systems.
The hydraulic system used during the trial is located on a production line used for retreating and inspecting strip material, driving actuators and web guiding systems in a 24-hour process.

"As drives can be used to accurately control the speed of most motor driven machinery, hydraulic pumps should be no exception in this respect," says Chew. "Hydraulic systems waste much of the energy used, because fluid circulates continuously, although actuation is only required for very short periods of time."

The energy used by the pump can be controlled by intelligently modulating the speed of the motor. The particular function used in this trial was the PID control, built into the ABB drive, which helps keep external values, like pressure, within certain limits. Pressure feedback is returned to the drive from a transducer. The drive automatically adjusts pump speed to maintain the system pressure.

Pump design reduces saving potential
Drives tend not to be used much on hydraulic systems, usually because the pressure is normally provided by a positive displacement pump, a type of pump that, theoretically, offers far less energy saving potential than the more common centrifugal pump.

Unlike a centrifugal pump, which uses centrifugal force to throw fluid out through the discharge end of the pump, the positive displacement pump uses an internal mechanism that presses the fluid out. This means the output will be the same regardless of the resistance on the discharge side. The internal mechanism can be some type of gear or an arrangement with vanes. The installation at Corus Colors uses a positive displacement vane pump, driven by two 37 kW motors, one duty and one stand-by.

Producing flow under pressure
Positive displacement pumps are used in hydraulic systems because this type of pump can produce high pressure despite high system resistance. A centrifugal pump is far less effective working against a high system pressure. Its actual capacity can be anything from 0 to 100% of full capacity, depending on the resistance produced by the system pressure. Because the pressure in a hydraulic system is very high, a centrifugal pump would not be able to pump much at all against this resistance. A positive displacement pump, in contrast, only shows a very small change of flow when the pressure goes up or down.

However, the energy consumption of the positive displacement pump is not reduced when the system resistance drops. For this reason, it does not offer the same energy saving potential as centrifugal pumps at reduced speed. While the centrifugal pump offers energy savings equal to the cube of the speed reduction, a change in flow by the positive displacement pump produces a linear change in power usage.

But despite using a positive displacement pump, Corus Colors achieved significant energy savings by retrofitting the existing system with a drive. The pump speed was greatly reduced both when the system was in neutral and during actuation of the cylinders.

Optimising speed
Chew's trial aimed to establish whether system pressure could be maintained with reduced average motor speed, using a drive, with pressure data fed back to the PID control of the ABB drive from a pressure transducer. The installation was commissioned on a downshift as other maintenance was carried out on the production line.

Vane pumps start losing their efficiency below 400 rpm, as the vanes are held in position by centrifugal force, so the pump efficiency had to be monitored throughout the trial as the optimum speed was sought. This was eventually established to be 450 rpm.

Chew had concluded that leaving the drive just running in PID control would cause some unwanted side effects. The main issue was that a drop in pressure would be followed by an increase in motor speed in response to the pressure drop.

The desired system pressure is 90 bar, while the maximum is 93 bar at full speed. As in many hydraulic systems, the on-load times are short. After actuation of the cylinders, the hydraulic system quickly settles back into neutral again. As the drive will have increased the motor speed rapidly to meet the drop in pressure, it is likely that it would overshoot the target of reaching a pressure of 90 bar, with the PID control having been set very high for a fast response.

The system relief valve is activated at 93 bar so the system pressure will never get higher that this. As the drive only sees a small error in pressure of 3 bar, it may be slow to react. This means there will be a long transient time before the drive settles down to the required speed to maintain 90 bar in neutral and this will cause unnecessary waste of energy, sending excessive fluid back to the sump while the hydraulics are in neutral.

Dual mode control
The solution was to operate the drive in two modes, PID control and single-speed mode. The switching between the modes is controlled by the transistor output of the pressure transducer. When the hydraulic system is in neutral and the pressure is at the desired level, the drive runs at a single speed of 450 rpm, the optimum speed established through the trial.

When the system is operated and the pressure drops, the transducer switches the drive into PID control. The desired pressure set in the PID is 93 bar, the maximum pressure for the system, and the proportional control is set very high to ensure a rapid response from the drive. Once the pressure increases to 90 bar, the transducer will switch the drive back to single speed mode. This will prevent any overshoot in speed and reduce energy waste.
The drive's hysterisis control is used to stop rapid switching which could wear out components and pulse the motor excessively.

Significant energy saving
Once Chew had established the optimum speed, wired up the transducer and programmed the PID control, the installation was monitored for two days to compare the energy consumption between under drive control with direct-on-line operation. Energy consumption was measured before and after using an energy meter.

When in neutral, power consumption was around 9 kW with direct-on-line operation. Under drive control, power consumption was reduced to 2 kW, a reduction of 77%. With the system under load, power consumption was reduced from 22 kW to 12 kW, a saving of 48%. As the on-load duty time for the system is 16%, the average energy saving over time was 70%.
"The reduction in energy consumption under load initially surprised me, as it should take the same amount of energy to move a hydraulic cylinder a given distance regardless of whether a drive or direct-on-line operation is used," says Chew.

Reduced peak power
An experiment was set up to test the hydraulics on direct-on-line operation and under drive control with a single actuation on the largest cylinder. To record the readings, the drive's internal recorder was used with the DriveWindow software from ABB. This gave high sample rates over a short period of recording time. The drive was set up to run at a single speed of 1470 rpm to the mimic direct-on-line operation. The recording was then started and the cylinder actuated five times, once every five seconds. The procedure was then repeated with the drive in the dual mode setup with PID and single speed.

The readings showed a similar performance between the two tests but a vast difference in energy consumption, the drive peaking at 20 kW while the system in direct-on-line mode peaked at 34 kW.

"The test showed that the drive used a lower motor speed to achieve the required pressure," says Chew. "The flow rate will be lower, but the drive is still fully capable of matching the response times of a direct-on-line configuration."

The reduced energy consumption will allow a payback time of just 18 months and reduce the company's carbon footprint by 33 tonnes of CO2 annually.

Energy consumption has quickly become a major global concern, as supply of  traditional fuels tightens, and as the serious consequences of greenhouse gas emissions become better understood. There is almost universal agreement for plans to cut carbon dioxide emissions, and most governments are putting forward plans to reduce the energy used in almost every aspect of human activity. Gary Nevison, head of legislation for Farnell, explains

Since lighting is estimated to account for some 10% of all electricity generated in the developed world, savings here can help significantly towards the overall global target. In Europe it is estimated the use of incandescent light bulbs alone results in the emission of 40 million tones of carbon dioxide per year.

Solution at Hand
Replacement lighting technologies are developing quickly, and low-energy Compact Fluorescent Lamps (CFL) and LED-based bulbs, that will replace incandescent and low efficiency halogen lamps, are already in stores. Companies have invested significantly in developing these technologies; for example, the advent of power LEDs for general lighting purposes has driven LED manufacturers and semiconductor vendors to roll out ranges of light sources and controller ICs optimised for a wide variety of applications. Major semiconductor vendors have also delivered new generations of electronic ballasts, which improve control and reduce start-up energy compared to conventional ballasts for fluorescent lamps.

Energy saving lighting represents a valuable opportunity for technology businesses, including component vendors and designers of lighting products. But market forces alone will not draw the desired response from consumers. Low prices for conventional incandescent light bulbs, for example, make it difficult for vendors of energy-saving products to convince consumers to pay the higher purchase price for CFL or LED technology.

Strong Arm of The Law
To overcome this reluctance in the marketplace, various elements of government legislation will at the same time push and pull energy-efficient lighting into the mainstream. On the one hand, schemes such as the EU's Ecodesign of Energy using Products (EuP) directive require companies to develop and improve energy-saving technologies. Studies cover office, street and domestic lighting. Other legislation - particularly green laws being considered overseas - will, as with the EuP Directive, actually force consumers to change their behaviour by banning inefficient older technologies such as incandescent lamps

The preferred route to reducing the carbon footprint of services such as lighting, is to impose restrictions at the product design level. The  EuP directive contains several examples of this approach. Its full scope reaches well beyond lighting, but a number of measures relating directly to product performance have been proposed to reduce the energy consumed, and extend the life of office, street, and domestic lighting. Increased efficiency in use, reduced mercury content, labelling and waste will all have to be considered for office lighting. Over time inefficient lamps will be phased out along with magnetic ballasts, even if luminaires also need to be replaced.

Fluorescent lamps are already widely used in workplaces throughout the developed economies, and the lamps installed may have electronic or conventional ballasts, or may be ballast free. Ballast design is already subject to energy efficiency targets under Directive 2000/55/EC, but the EuP proposals call for a further tightening of the limits. Power consumption when the lamps are ‘off' will initially be limited to 1 Watt dropping to 0.5 Watts after 3 years. Lamps without integral ballasts are currently graded according to efficiency, and the EuP directive proposes eliminating the lowest efficiency bands. At the same time the highest efficiency band will be subdivided, which will differentiate the most efficient products. Luminaires will also be subject to minimum limits for light output efficiency, and supporting documentation will also be required to detail lighting efficiency (up and down), ballast efficiency and instructions on cleaning, maintenance and installation.

Regulations relating to materials and production processes are also being considered. Although the mercury content in CFL lamps is well below the limits specified in the now-familiar RoHS directive, separate proposals for lighting recommend a lower limit of 2mg for lamps without integral ballasts.

As far as street lighting is concerned, vendors have considerably improved product efficiency over a number of years. However, since individual units can remain in service for up to 30 years, technology advancement alone may not deliver energy savings quickly. The  EuP study calls for tougher efficiency targets, and these will effectively allow only the most efficient high-intensity discharge (HID) lamps. For maximum effectiveness, the performance of the control units for each lamp may also need to be governed.

According to the European Commission, these improvements in office and street lighting, when fully implemented, could save around 15% of the energy currently used - equivalent to the total annual electricity consumption of Romania.

Reaping the rewards of low energy lighting throughout private homes is more difficult to achieve, since homeowners are generally less easily persuaded to pay the higher purchase price for the newer technology. Some governments clearly feel that more positive action is required: in 2007, Australia became the first country to announce an outright ban on incandescent bulbs. The US Energy Independence and Security Act also effectively means the end of the line for the incandescent in the USA, by requiring that all light bulbs must be 25 to 35% more efficient by 2012 to 2014. The EuP's view on domestic lighting proposes either to ban incandescent bulbs or to impose such stringent limits on efficiency that only straight fluorescent lamps, the best CFLs and some halogen lamps will achieve approval.
The EU's Energy Commissioner, Andris Piebalgs, has said that eliminating incandescent bulbs could save households up to e50 per year. This saving must be balanced against the higher selling prices of low-energy bulbs, and will weigh in favour of low-energy products as market forces and climate change levies combine to produce rapid increases in energy prices.

Upholding Standards
In describing wider effects of the EU lighting directives, Piebalgs has claimed that homes will keep the same quality of lighting. But this is in the hands of product designers. Although high-quality CFLs do produce illumination comparable to that of incandescent bulbs, the performance of budget models is far less consistent. LED technology, however, is still maturing, and components and systems must still improve to achieve performance parity while meeting industry-standard form factors. Energy-saving lighting for use in offices and factories must also meet health and safety standards, such as minimum standards for workplace illumination. Similar specifications apply to street lighting and signage, as well as municipal lighting such as in public places and car parks.

Hence the legislative framework surrounding lighting requires product vendors to take responsibility for delivering energy savings as well as performance enhancements, but also includes some measures that effectively ensure a viable market for the fruits of their labours.

As more businesses switch on to the benefits of energy saving and with legislations in existence, which demand better use of electricity, emphasis is being placed on efficient products and solutions, including lighting systems. The decline in new build premises means when looking to make businesses more efficient, existing buildings need to be improved and, as such, the demand for retrofit lighting controls and systems is big business for contractors at the moment. David Lewis from Schneider Electric looks at the technologies and solutions available

Commercial premises and public buildings are coming under increasing pressure to improve their energy efficiency. Legislation such as the EPBD (Energy Performance in Buildings Directive), which requires an EPC (energy performance certificate) to be awarded depending on the carbon output of the building, coupled with rises in fuel bills, has placed the topic high on the agenda of many organisations.

In the past, businesses may have moved to new premises when the property they were occupying no longer met their requirements. However, the global economic situation has led to a dramatic decline in the number of new build commercial properties and companies are instead modernising their premises to help reduce energy consumption.

As a result, there has been increased demand for retrofit solutions that not only reduce energy usage but are easy for a contractor to fit, keeping installation costs to a minimum.
In commercial and public buildings, lighting can account for up to 40% of the total energy consumption so, when looking to improve energy efficiency, it is a good place to start. In addition, the range of energy efficient retrofit lighting components is vast and a suitable solution can be found for every type of space.

These retrofit solutions make reducing energy consumption from lighting quite straightforward. Although investment needs to be made, modern technology makes the process easy, as long as four simple steps are followed; measure, fix the basics, automation, and monitor and improve.

Before energy efficient products and solutions can be installed, the building's energy consumption must first be measured via an energy audit. Sub-metering products, such as Schneider Electric's EN40, a single phase kW/hour meter, can monitor the lighting load of individual rooms, departments or buildings to look for patterns of usage that can be controlled. Once this has been completed, areas/periods of high electricity consumption can be identified and this information is then used to form a lighting strategy for the premises.
The lighting strategy will depend upon the individual rooms' periods of use, occupancy, and levels of natural light, so that the lamps only come on as necessary and to the intensity required. It sounds simple, but the best way to save electricity is to switch the lights off when not needed, so this should form the basis of the lighting strategy.

The most obvious way to do this is to educate staff, by asking them to only have lights on when the room is occupied, but for greater control, switches, timers, impulse relays and/or presence detection solutions can be used.

Timers are simply set so the lights come on when the building is open and switch off when it is closed to ensure they are not left on unnecessarily. However, this does mean lights are often left on when a room is unoccupied and to overcome this, impulse relays or presence detectors can be installed. Impulse relays are switches that include a timer, which turns the lights off after a set period, ensuring they cannot be left on unnecessarily. This is the type of lighting control often found in hotels where corridors are frequently unattended for long periods of time. Presence detectors differ in that they detect movement within the area and switch the lights on accordingly, so when there has been no movement within the room for a while, the lights will switch off again. This is ideal in areas which have unpredictable occupancy such as offices and meeting rooms.

In addition to switching off lighting when it isn't required, energy consumption can be reduced by decreasing the output of the lamp through dimmer switches. These can either be manually controlled by the occupants, or can be light level based to achieve what is commonly known as daylight harvesting. This is achieved by using sensors, which monitor natural light levels within the room and then supplement any deficiency with the lamps. They are therefore commonly used in situations where the atmospheric conditions of the room are important. For instance, recent studies have shown how lighting levels have an impact on children's learning - if the room is too bright or dark concentration levels can be affected, so moderating the lighting both reduces energy usage and improves the environment for users.
As well as switching off and dimming, voltage reduction can also lower energy usage in lighting, particularly in outdoor situations, for example car parks and playing fields. Voltage regulation technology, such as Schneider Electric's Lubio, actually reduces the supply voltage to the lamp according to the individual demand. This not only decreases the amount of electricity used but also extends lamp life and reduces maintenance, both of which can save time and money.

All of these individual components can be used standalone or as part of a complete lighting strategy, however, individual component control is only really ideal when energy consumption needs to be reduced in areas with just a few independent luminaires. When usage needs reducing for an entire lighting structure, a control system approach should be adopted. This is where the individual components can be linked by a control panel or automation system.

Control panels can be situated either in the room they manage or within a dedicated control room. This allows for timer programming as well as manual override of the switch technologies installed. For instance, if the lights need to remain on in an unoccupied room and presence detectors are installed, the infrared sensors can be overridden, or if lights need to be dimmed or brightened for a specific purpose, the light level sensors can be switched off.

In major refurbishments or new build projects, the lighting and energy consumption can be controlled though an automation system from one location. Systems such as C-Bus from Schneider Electric can be programmed to monitor the lighting and manage it automatically. In addition, they can be reconfigured as and when space needs change so the lighting within the building remains flexible.

Lighting control systems can be linked to a BMS (building management system) to share information with other processes such as heating, hot water and air conditioning. By doing this the whole building can become ‘intelligent' and energy consumption can be reduced dramatically. For instance, if there are increased levels of natural daylight within a room, the chances are the temperature will rise as well so the system can use this information to control heating levels. The presence detectors in an office can also be used to switch the air conditioning on and off, so it is only operating when the room is occupied.

Once these energy saving measures have been put in place, the electricity consumption can be measured and monitored to ensure that savings are being made. Reducing energy usage is an ongoing challenge and, by constantly measuring it, improvements can be made to the system as and when it is necessary. If a lighting system is not achieving optimum savings, the technology can be readdressed and adapted to ensure legislation requirements are met and electricity bills are reduced.

Lighting is just one element where energy consumption can be reduced but, because it accounts for a significant proportion of a building's electricity usage, the potential savings are massive. Furthermore, the retrofit lighting components available are easy to install, with minimal disruption and without the need for system integration to facilitate energy reductions, making them a cost effective way to improve carbon emissions and a company's bottom line.

"Steel wire tray systems can offer greater flexibility, faster installation and significant cost savings when compared to traditional perforated tray, but it's only when the installation team is well trained in how to use the system to its best advantage that these benefits can be fully realised." That's the view of Tim Brown, Specification Manager at Cablofil UK, and it's an opinion based on wide-ranging experience of visiting contractors on site and delivering training to help with both a general understanding of the product and site-specific challenges

At Heathrow's T5, where the Cablofil system was used by several contractors for various aspects of the project, the Cablofil team made many training visits to site and helped to engineer containment solutions alongside the installation teams.

"To my knowledge," comments Tim Brown, "we are the only cable containment manufacturer that offers to provide training to our customers as an integral part of our product offering.  To us it simply makes sound commercial sense as it not only adds value for our customers but it ensures they use the system to its full potential, which underpins the quality of the installation for the end user."

Engineering Solutions
Cablofil provides training both for contractors who are new to the company's system, or to steel wire tray per sé, and to those who use it regularly.  As a result, training is provided on two levels; as a basic introduction to teach installation teams how to cut, bend, shape and join the system or as a troubleshooting session for contractors already experienced in using steel wire tray systems but keen to access the expertise of the team to help them address specific challenges on site.

"It can be frustrating sometimes that customers don't call us in until they are experiencing difficulties on site," says Brown, "as often we could have saved them time and money if they had brought us in at the beginning of the installation and allowed us to help with finding solutions for the more difficult aspects of the project.

"We often help contractors to find the simplest solution for the installation, which sometimes means reducing the number of components used and therefore saving time and money on the job!  The manufacturer's experts can also fabricate any of the trickier aspects of the installation for use as a kind of template so that the installation team can simply reproduce it as required on site."

Timely Teamwork
Cablofil typically arranges training in consultation with the project engineer, site manager or foreman and it is normally carried out on site after the product order has been placed, but before it has been delivered. Depending on site-specific constraints, the hands-on tutorials may take place in a suitable site office, a siteguard (lockable container to secure valuables on site), at the workface or even in the car park, but whatever the location, they are tailored to meet the actual, practical, working requirements of each project.

Involving a group of around ten people, a typical training session usually only takes about 30 minutes.  The training engineer is equipped with a few short lengths of steel wire cable tray, together with a range of accessories such as EDRN couplers, Fastrut 41 channel clips and other potentially time-saving components that may be appropriate to the specific project. Having first established if any of those present have previous installation experience with wire tray, the primary objective is to enable the product to be installed quickly, easily and safely, demonstrating how bends, tees and other necessary accessories can be formed as required. 

The initial part of the session is used to show the comparative speed with which two lengths of cable tray can be joined using the Fast Coupler EDRN. Most installers are used to joining lengths of traditional perforated sheet steel tray in a couple of minutes or so, but two similar lengths of steel wire tray can be securely joined in no more than 20 seconds and each member of the group is encouraged to practice applying the couplers and removing them safely.

The training engineer proceeds to cutting and forming the cable tray using the bolt-croppers specifically designed to cut wire cable tray. The croppers are capable of cutting the maximum steel wire gauge of 6mm, the jaws being designed to give an offset cutting action across the welded intersections on the tray, reducing spurs and sharp edges. To demonstrate how the tray can be cut correctly, it is placed with the base uppermost and, for the first cut, the croppers are placed with the jaws held firmly against the longitudinal wire. The natural loft of the jaw provides the correct cutting angle while the ‘beam' wires that cross the tray are used as a guide.  The top ‘safety' wire can be safely cut by aligning and angling the croppers. Again, the participants are each given the opportunity to carry out the cutting operations, before moving on to follow the training engineer's example in forming ‘accessories' including gusset flat bends, internal bends and angled bends.

With the principal training tasks completed, the Cablofil trainer examines the planned installation, confirming that all available options have been considered in terms of fixing brackets, loading capacities and spacings. While the basic straight lengths of tray, couplers and four-piece assembly kits may well have been placed on order, it is not uncommon for the installer to have overlooked the need for specific support or suspension brackets and fixings. 

"Because training is arranged to take place before any final deliveries are made," Brown explains, "during training the trainees may become aware of brackets or accessories they wish to use on the project, saving time and money without delaying the installation programme."

"It doesn't matter how large or small the installation is, the small time investment in training can significantly reduce both the installation time and component costs, which is better for both the contractor and the end user."

 

NG BAILEY: SWITCHED ON TO EXPERT TRAINING

Training the next generation of electrical engineers is something building services provider, NG Bailey, takes very seriously. The company runs its own Engineering Academy where it trains around 80 apprentices each year. The students experience a mixture of classroom training and on site practical experience and, towards the end of their course complete a full scale installation at the academy's practice building. For the past four years, Cablofil has been delivering training sessions at the academy to help the apprentices learn about different types of containment and become familiar with how to use the steel wire tray system.

"Cablofil is one of our key suppliers," explains head of the Bailey Engineering Academy" Alison Ashworth-Brown, "working very closely with us to engineer the solutions we need on site. The training they provide us is of great value and currently they carry out two or three sessions a year."

The Cablofil team delivers the sessions at the academy towards the end of the students' second year apprenticeship.

"We begin the session with a presentation," explains Tim Brown. "We take the students through the different methods of containment, the pros and cons of each and the reasons for using containment in different applications. Once they understand the background, we then talk more specifically about steel wire trays and about how containment has developed thanks to the introduction of systems like Cablofil, before we let them get to grips with the product itself."

Following the classroom element of the training, the team demonstrates how to cut, bend and connect the system and guides the apprentices through the process as they practice using the system themselves. The hands on experience of using the product under the supervision of experts from the supplier gives the apprentices confidence and by the end of the half day session each apprentice will have learned to cut and couple the product and have produced both a 90° bend and a T junction. Once they have shown they can complete these fundamental elements of using the system, each apprentice is issued with a certificate from Cablofil.

"The trainees at our academy are at the beginning of their career and usually still teenagers," says Alison, "so having Cablofil come in and train them gives them great confidence and a practical skill that they can use straight away."