electrical review august-2010
TRANSCRIPT
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Inside this issue:
I Technology improves cable fire safetyI SIMply the best for fault location
I SuperCap UPS fast response, long lifeIMethodical risk identification
MINISTER ANNOUNCES 8.4MPLASTIC ELECTRONICS INVESTMENTA range of specialist plastic
electronics businesses are to
benefit from a total of 8.4m
investment in research and
development into new technologythat will lead to the creation of a
range of new products such as
conformable and rollable electronic
displays, ultra-efficient lighting and
low-cost, long-life solar cells.
The investment was announced
by the universities and science
minister, David Willetts, during a
speech to the Tomorrows Giants
conference in London. Thirteen
projects, involving more than 30
industrial and academic partners, will
benefit from the funding allocated as
a result of two competitions run by
the government-backed Technology
Strategy Board.
Minister for universities and
science David Willetts said: It is
early days for this emerging field,
but plastic electronics will give rise
to a range of new excitingproducts, such as ultra-efficient
lighting and cheaper, longer-lasting
solar cells. Looking ahead, this
technology offers enormous
potential to help our local
environment, improve our everyday
standard of living and support the
nations economy.
The global market for plastic
electronics is now worth almost
$2bn (1.337bn) and is forecasted
to grow to as much as $120bn
(80.19bn) by 2020. The funding
Ive announced today is important
in supporting UK businesses to be
world leaders in one of the key
industries of the future.
Commercially exploiting the
outputs of the UKs world-leading
science and research base has a
vital role to play in helping oureconomy to grow.
7.4m has been offered to eight
projects to help build the supply
chain and to overcome the barriers
to UK exploitation of plastic
electronics technology, including
over 800,000 from the
Engineering and Physical Sciences
Research Council (EPSRC). A further
1m has been offered by the
Technology Strategy Board to five
projects to encourage UK
businesses to use plastic electronics
in their product development by
producing demonstrators with
potential for real commercial value.
News Page 3 Power cables Page 10 UPS Page 20 Building services Page 24
August 2010 Volume 243 No 8
KNX UK Association member
Andromeda Telematics (ATL)
was shortlisted in the KNXInternational Awards, presented
at the 2010 Light+Building
Exhibition in Frankfurt, for the
company's O2 project in Dublin.
The project is a showcase of
progressive design and building
services providing an integrated
control solution for the
renovation, delivering KNX/DALI
colour change functionality as
well as an emergency lighting
test system.
The KNX/DALI solution
includes lighting scene control
for public areas, controllable via
local touch screens and a central
headend. There is also local
scene set control and dimming
in the private bar areas, as well
as local control in all back-of-
house areas for override of
lighting condition. The external
lighting controls feature lux
sensors which activate lighting at
dusk. An override function isavailable for periods where the
building is unoccupied.
For the latest news, products and event information visit www.electricalreview.co.uk
ELECTRICAL
REVIEW
TUV ACQUIRES LAIDLER GROUP SHARESTV Product Service, a UK subsidiary
of the TV SD group, has acquired
the shares of the Laidler group of
companies, the UK machinery safety
compliance organisation. Operatingfrom offices in Cleveland and
Yorkshire, the Laidler group has
consolidated sales of 2.6m and 30
employees.
The acquisition of Laidler brings a
wealth of experience in machinery
safety to our UK organisation and aposition in the UK that is second to
none, said Jean-Louis Evans,
managing director of TV Product
Service. We feel there are
considerable synergies between our
organisations and bringing the two
organisations together will establish amuch stronger Machinery Safety
business for TV SD in the UK.
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Nexans has signed a draft agreement for the
creation of the trans-Mediterranean super-grid
Transgreen with 12 other industry partners, in
the presence of the French minister of ecology,
energy, sustainable development and sea, Jean-
Louis Borloo, the French Republic presidents
special advisor, Henri Guaino and the French
secretary of state for european affairs Pierre
Lellouche.
Transgreen is an unprecedented industry
initiative aimed at studying the feasibility of a
power transmission grid between the northern
and southern shores of the Mediterranean and
at developing interconnections around the
Mediterranean Basin. It is part of theMediterranean Solar Plan (MSP), which provides
for the building of renewable mainly solar
power generation facilities in the southern and
eastern areas of the Mediterranean, with a total
output of 20 GW by 2020.
The 13 signing companies will collaborate
within a common legal entity, especially in
order to propose the technical and economical
master plan for a trans-Mediterranean super-
grid with 5GW export capacity to Europe by
2020.
Nexans generates about half of its sales inthe infrastructure market and has recognised
expertise in the design and installation of high
voltage submarine power links, therefore it was
obvious for us to participate in Transgreen. As
access to electricity remains a vital need for
human beings, it is more essential than ever to
get involved in responsible projects which make
it possible not only to build and interconnect
new grids but also to develop renewable
energy resources, said Frdric Vincent.
Power grid performance is central to Nexans
strategy. In fact, Nexans offers a complete
portfolio of terrestrial and submarine high-
voltage AC and DC cables and cabling systems,
with products and services which enable
integration of alternative energy sources into
the grid, real time monitoring of infrastructure
for increased reliability and installation of newmaterials including superconductorsfor
improved performance.
Leveraging its expertise in high-voltage
submarine power transmission, Nexans has
many references in this field, such as the link
between Morocco and Spain, the NorNed link
between the Netherlands and Norway and,
more recently, the COMETA link between the
Spanish mainland and the Balearic Islands. In
recent years, Nexans has also demonstrated its
skills in connecting renewable energy resources
by participating in numerous offshore windfarmprojects worldwide, including Barrow (England),
Horns Rev (Denmark), Lynn & Inner Dowsing
(England) and Wolfe Island (Canada).
Siemens is to supply 68 wind turbinesfor the Griffin onshore wind farm inScotland. The wind power farm willhave a capacity of 156 MW upon itscompletion in 2012, and is expected togenerate enough power to supplyover 80,000 homes. The scope ofsupply for the Griffin wind farmincludes the delivery, installation, andcommissioning of 68 of Siemens 2.3-MW turbines. Of the 68 turbines, 61will have a 101m rotor and 7 will havea 93m rotor. This is the first time aSWT-2.3-101 will be deployed in the
UK. Siemens will also provide servicesfor turbine operation andmaintenance for an initial period offive years.
TRANS-MEDITERRANEAN GRID
SIEMENS WINSWIND CONTRACT
CONTENTS
03 | NEWS06 | OPINION08 | GOSSAGE12 | POWER CABLES
16 | ARC FLASH22 | UPS
25 | PRODUCT WATCH26 | BUILDING SERVICES32 | CLASSIFIED35 | BLOWN FUSE
When a power service
engineer is called out to
deal with a loss of
supply on a customers
HV distribution
network, the chances
are it will be traced to a
faulty undergroundcable that has caused a
device such a circuit
breaker to operate
and cut off the power
With IT central to the
successful operations
of most modern
organisations, the
UPS system has a
central position in the
critical physical
infrastructure which
supports servers,
storage and
communications
equipment, and
ensures continuity ofservices during all
local mains conditions
Recolight, the specialist WEEE compliance
scheme for the lighting industry, has
announced a partnership with recycling
scheme, CoBRA (Community Bulb Recycling
Alliance) to increase consumer access to
collection facilities for low-energy light-bulbs.
Founded by Mark David Hatwood in 2007,
CoBRA was initially established to provide
community recycling for waste batteries. The
scheme works by recruiting volunteers to place
collection containers in community locations
and then take responsibility for collecting the
waste and taking it to a central collection
facility. Through this partnership with
Recolight, the CoBRA scheme will be adaptedto provide community collection of low-energy
light-bulbs, using Recolights new in-door
light-bulb collection container.
SCHEME TO INCREASE
LAMP RECYCLING
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EDITORElinore Mackay 020 8319 [email protected]
ADVERTISEMENT MANAGERNeil Coshan 020 7933 [email protected]
PRODUCTION MANAGERTania King 020 7933 [email protected]
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PUBLISHING DIRECTORChris Cooke
PRINTING BYWilliam Gibbons
Any article in this journal represents the opinionsof the author. This does not necessarily reflect theviews of Electrical Review or its publisher StJohn Patrick Publishers
ISSN 0013-4384
All editorial contents Saint John Patrick
Publishers Ltd 2010. Jan-Dec 2009 6,484
NEWS
The new ABB swappage scheme is supported by
a recycling programme that this year recycled 13
tonnes of waste variable speed drives, recover-
ing over 90% of their component materials by
weight. The ABB swappage scheme offers at
least 17.5% off the list price of a new ABB drive
and will swap out incumbent drives from any
manufacturer.
The ABB recycling programme, now in its
eighth year, takes these scrapped drives and re-
cycles them according to the WEEE Directive, even
though drives are not covered by the legislation.
Once the drive has been removed for recy-
cling, ABB issues a certificate that can be used
for environmental audits by end users complying
with ISO 14001.
PROGRAMME RECYCLES13 TONNES OF WASTE VSDS
David Pollock, group chiefexecutive officer of theElectrical ContractorsAssociation ECA, will retireat the end of September2010. His successor will beSteve Bratt, C Dir, MBA, theECAs Deputy CEO.Following his retirement,Pollock will continue as anadviser to the association; hewill represent ECAs interestsin Europe and in lobbyingand representational work.Pollock said: I have spent anexciting and fulfiling 13 yearswith ECA. I am very gladthat Council has agreed thatmy successor should be SteveBratt. I wish him, ourPresident, Diane, the otherOfficers and all the Membersand staff the greatestpossible success. I amlooking forward to a very
active retirement and I am glad I shall becontinuing to represent the ECA in someimportant areas.
Balfour Beatty Engineering Services BBEShas announced a key business developmentappointment. Henry Mayes has joined thecompany as business development manager forLondon and the South East. Mayes will reportto business development director Bill Merry,and will assume responsibility for new businessdevelopment. He joins from M&E designconsultant Maleon and will be based in theRedhill office.
Hochiki Europe has announced a series ofsenior level appointments that will drive thecompany forward and strengthen its marketposition. Tomoki Ikeda pictured is now themanaging director of Hochiki Europe, while hispredecessor, Minako Adachi, stays within theHochiki organisation as its executive officer ofoverseas division based at HochikiCorporations Headquarters in Tokyo, Japan.Meanwhile, Kevin Restell has been promoted asHochiki Europes operations director and joinsthe board of directors.
PEOPLE
HenryMayes
TomokiIkeda
DavidPollock
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OPINION
HOW MANY electrical contractors does it take to
change a light bulb? It doesnt really matter,
because, with the double focus nowadays on
health and safety and sustainability, the real
question should be: Do they know whats
being done with the old one?
As efficient electrical waste disposal gets
both more complex and more necessary for
financial, operational and legal reasons - those
nvolved in electrical engineering and building
services would be unwise not to pay heed to
the answer, a fact that one recent prosecutionhas shed some revealing light on.
The sustainability lobbys continued success
n promoting the balancing of successful
business with effective environmental
protection (not to mention the wellbeing of the
mmediate workforce) has ever greater
ramifications for the industries responsible for
creating and managing the built environment.
Sustainability, above all, is an area where
electrical contracting, now worth some 8bn
per year, has a key role to play, with the
opportunity to propose low or no CO2 options.
But to play its role successfully the industry
must also pay close attention to the matter of
the waste the alternative option creates, and
how it is disposed of. Developments such as
the WEEE regulations (Waste Electrical and
Electronic Equipment Directive) impose legal
obligations on contractors over the
management of waste streams onsite, and in
their subsequent disposal. It aims to improve
the environmental performance of businesses
that manufacture, supply, use, recycle and
recover electrical and electronic equipment
and has put the practical management ofsustainability centre stage. For the electrical
contractor its implications are unavoidable.
Energy efficient light bulbs (end-of-life gas
discharge lamps) are covered by the WEEE
regulations and present a particular challenge,
because they contain mercury and are classified
as hazardous waste. When these lamps are
recycled the potential release of mercury into
the air at the lamp crushing stage is a threat to
both the wider environment and those in the
vicinity if the right protective equipment is not
in place. Each time a fluorescent bulb is
crushed or broken, mercury vapour is released.
If the gas is not effectively captured, that
vapour will find its way into the atmosphere,
the staff and others in the area.
The challenges of lamp recycling made
headlines earlier this year when a Glasgow-
registered company, Electrical Waste Recycling
Group, and one of its directors, were fined a
total of 145,000 plus costs after recycling
processes being used for gas discharge lamps
exposed workers to toxic fumes for a period of
up to ten months.
If an electrical contractor is going to proposethe likes of optimal lighting configurations or
energy efficient lighting units, and if they are
tempted to employ energy efficiency as a sales
tool, they should be confident that the
principles and practice that underpin
sustainability and safety are being applied all
the way through the supply chain, including
what happens to the waste.
Bulb crushing on an industrial scale is a
serious undertaking that comes with huge
levels of environmental responsibility.
Nevertheless, electrical contractors may face the
prospect, perhaps even at the tendering stage,
ELECTRICAL CONTRACTORS
CAN NOT AND MUST NOT
TAKE THE RECYCLING OF
FLUORESCENT BULBS LIGHTLY
SAYS TERRY ADBY Shedding lightRESPONSIBLY
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of client pressure to commit to deliver such a
service. Contractors need to be completely
confident of the ability of the suppliers they
choose to meet their commitments. They also
need to know what is being done in their
name further down the supply chain.
In the case of Electrical Waste RecyclingGroup, it was the failure to ensure the safety
of the lamp crushing phase of the recycling
process at its Huddersfield plant that let
down the company, their workforce and the
local environment. EWRG, which runs
easyWEEE, WERCS (Waste Electrical Recycling
Compliance Scheme) and other recycling
schemes, were contracted to handle
commercial waste for several Local
Authorities, which included light bulbs. While
none of these clients were in any way
implicated along with their supplier, thejudgment in the case suggests others in the
chain such as electrical contractors - could
be more vulnerable. It has already been
indicated in court that putting a service out to
a third party does not absolve an organisation
of key responsibilities and, in respect of
health & safety, the HSE - which brought the
successful prosecution in the EWRG case - has
said that The client must ensure whoever
carries out the work is able to do so in a way
that controls risks. As this case suggests,
sustainability and health and safety
responsibilities often go hand in hand.
Some of the details of the EWRG judgment
highlight the type of issues any business,
including electrical contracting businesses,
should take into account to ensure they and
their suppliers comply with statutory
requirements when dealing with waste. The
promises of suppliers, the judge made clear,are no defence in the eyes of the law. They
must be effectively monitored.
One of the judges major criticisms was the
lack of an effective risk assessment process at
the EWRG recycling centre, not least because
issues highlighted such as excessively high
mercury levels for no apparent reason - could
have been rectified much earlier had risk
assessment been in place. It is, in any case, a
legal requirement for an employer in
discharging their obligations to keep workers
and the public safe as far as "reasonablypracticable".
The HSE recommends five steps for effective
risk assessment: identification of hazards;
establishing who might be harmed and how;
evaluation of risk and deciding on precautions;
recording and implementing findings and
regular review. Suppliers in a business as
hazardous and regulated as lamp recycling
should certainly be implementing all five.
Those employing them to do the work should
be equally concerned that they are.
The judge in the EWRG case also stressed the
need for competent staff to be involved in the
process monitoring, who understand the
regulations and have the knowledge and
experience to spot a breach or issue. Most
successful organisations, he said, have
employees who understand why risk
assessment and vigilance is important for the
company, staff and other groups with aninterest, such as the local community.
However, all responsibility cannot be
delegated to one individual or team, he added.
Senior managers need to put themselves in the
position of being able to interpret and
understand the implications of the results of
any monitoring which is undertaken. If they do
not understand the implications of results, they
cannot just ignore them. In the case of a
prosecution it will be the senior managers and
directors who will be held responsible. It is
clear, above all, when things go awry, buckpassing between organisations or individuals is
not an option.
EWRG paid a heavy price because it did not
read nor heed the warning signs. Those looking
for lessons from its prosecution certainly
should however. The safe recycling of energy
efficient lamps may represent a beacon for a
better future but, viewed from both an
environmental or health and safety perspective,
the message for electrical contractors is clear:
the responsibility for a safe and sustainable
approach to lighting may not end with the life
of the low-energy bulb.
OPINION
When things go awry, buck passing between
organisations or individuals is not an option
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OPINION
CHALLENGE TO YOUNG RIVALGOSSIP!
GOSSAGE!
HEBRIDES RAINDANCE
LEARNING TIMES TABLES
08 Electrical Review August 2010
The Climate Change Committee is a frightfully important entity. Formed as a
result of the Climate Change Act 2008 to ensure the UK remains on track to be
the worlds most eco-friendly nation, it consists of a set of Commissioners
drawn from the Great and Good. Led by the former head of the CBI, Adair
(now Lord) Turner. Who also heads the Financial Services Authority in his
spare time.
Periodically the Committee issues large reports. Which consistently seem to
conclude that, whilst the UKs aspirations to reduce carbon dioxide emissions
are splendid, we must do better regarding progress on the ground. These
reports are littered with serious statistical recommendations for how best
progress should be made. Each of which the government is supposed to act
upon immediately.
However, dig a little deeper. And you do begin to wonder just how reliable
some of the figures are. For instance, when launching the latest progress
report, mLord Turner thundered that to keep the eco-trajectory going - the
number of homes where insulation is placed within the external cavity walls
should be running at 1.2m each year. This means doubling the number
currently being insulated.
His Lordship did not misread his script. The accompanying press release
contained precisely the same demands. The number of homes each year
having cavity wall insulation installed must be doubled. No less than 1.2m
should be improved each year. But if you consult the official agency that
issues guarantees after every such installation, they will tell you that this year
the total number of homes benefitting is around 400,000. Getting the rate up
to 1.2m a year wouldnt be doubling. It would be tripling the size of themarket. If Lord Turner really cannot tell the difference between times two
and times three, it is probably a relief to know his spare time job chairing
the Financial Services Authority is coming to an end.
I have in the past chronicled the woes of the previously highly successful
Renewable Energy Association. Not least when in 2008 a lowly book-keeper
in the finance department absconded with 247,000 of its members cash.
Which on a turnover of 604,000, left rather a large hole in its finances.
Membership fees were immediately hiked, some by over 20%. Several
companies opted out. Its founder and CEO Philip Wolfe took early
retirement. And one long-established rival association suddenly woke up to
the opportunities offered.
The British Wind Energy Association (BWEA) had been around since 1978.
Despite windpower being far and away the largest renewable power option,
it remained unconcerned about its younger rival the Renewable Energy
Association covering not just all the other non-fossil fuel options. But also
bringing into membership many of the big players, especially in the
burgeoning off shore windpower field.
This year the BWEA has had a complete shake-up. It has re-examined its
objectives. It has brought into membership new companies (some 600 now).
And most significantly it has changed its name. To become RenewableUK. A
direct challenge to the wounded upstart, the REA.
No question where Whitehalls sympathies lie. Whilst chief executive Maria
McCaffrey MBE remains in post, despite the name change, ministers and top
civil servants queue up to appear on her public platforms, meet with her
privately, all signs of official approval. I was going to say let battle
commence. But actually I rather think the battle is already over.
They are praying for rain in the Hebrides. Most especially on the
picturesque island of Eigg. Because the 70 people who live there
would like to go back to having toast for breakfast.
Normally practically all the islands electricity is provided by
hydro-power. But as there have been three months with almost
no precipitation, the islanders are having to forgo using any of
their optional electrical appliances. Like toasters.
This is not the first time there has been insufficient rain to
power the island. Which is precisely why they have retained
diesel generators for back-up. However there is a distinct
reluctance to bring these back into use.
Why? Because just last January, the community took up a
challenge of a 300,000 prize (amongst 700 people!) to becomeone of Europes lowest carbon communities. And that could be
forfeited if they succumb to cranking those old diesel generators
back into action.
THE NEW ASBESTOSCheerleaders for the Great God Atom like to promote its virtues by
emphasising how nuclear can substitute for energy imports. And
particularly energy imports from unreliable countries. Whilst that is
certainly not true for most of the components nor of their suppliers, most
of which are definitely neither UK owned nor domiciled, there is one key
component which everyone accepts simply can never be found on these
shores.
There are only a handful of counties around the world where uranium
is to be found. According to that impeccably neutral source, the World
Nuclear Association, the total amount of recoverable uranium supplies
worldwide is some 5.469,000 tonnes. Concentrated in a very few places.
By far the biggest of these is Australia, with 1,243,000 tonnes. Where
curiously enough no nuclear power is permitted.
Australia has been the most reliable past supplier. But will it be in
future? Not if the powerful Australian Electrical Trades Union has its way.
It is banning its members from working in uranium mines because and I
quote uranium is the new asbestos in the workplace. Australian
unions, particularly as now under a Labor government, are not to be
trifled with. If they wont mine the stuff for health reasons, chances are it
wont get mined.
But whilst it is the biggest potential source of uranium, Australia is notthe only one. There are other countries with substantial reserves. The next
two biggest are Kazakhstan (with 817,000 tonnes). And Russia (546,000
tonnes). Obviously it is perfectly possible to trade with both countries. If
the promised expansion of nuclear ever goes ahead, we may well have to
do so. But do remember. These are precisely the kind of unreliable
suppliers which those in the nuclear lobby who scare us about the
dangers of energy imports endlessly warn us about.
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POWER CABLES
The microstructure of the
Infit insulation after a fire
(magnified 5000 X in an
electron microscope)
On the left, the Infitinsulation after a fire and
on the right, conventional
insulation
10 Electrical Review August 2010
FIRE-RESISTANT cables play a crucial role in applications
where it is essential to ensure the integrity and continuity
of vital safety circuits during the critical building
evacuation and fire fighting periods required by stringent
national and international standards. In many cases, the
need for cables that can deliver the required levels of
performance, reliability and safety has forced designers
and installers of electrical systems to compromise on
other desirable properties regarding ease of handling andinstallation.
Now though, a major advance in the materials science
related to the properties of the cable insulation called
Infit is making it possible to produce new families of
electrical power and data cables with outstanding fire
resistance using classical extrusion methods. The result is
a user friendly cable that offers the best of both worlds.
Eliminating the need to chose between insulationtechnologiesUntil now, the cable industry has mainly relied on two
major technologies to insure the integrity of flexible cableinsulation during a fire: XLPE/Mica taping and ceramic
forming silicone rubbers.
Each of these technologies presents a number of
advantages. The classical insulation taping based on Mica,
and largely used since the 80s, can easily be implemented
on an industrial scale to provide a tough, effective
electrical insulation when overlaid with a cross-linked
polyethylene (XLPE) coating. It is strong but stiff to handle,
so can present some installation difficulties.
On the other hand, silicone rubber insulation can be
extruded directly on to the conductors, and offers a good
compromise between fire performance and ease of
installation thanks to its flexibility. It is, however,
vulnerable to cuts and tears.
Increasing customer demands for improved fire
performance, together with strippability, ease of
installation and connection prompted Nexans to searchfor a new insulation technology that could offer all these
benefits.
Infit transforms into a tough insulating ceramiclayerInfit is a unique, proprietary innovative technology that
combines, in a polymeric material, the advantages offered
by both the tough mica tapes layer and the extruded
silicone insulation layer. This now enables the manufacture
of fire-performance cables that are both tough and easy to
handle as well as being easy to strip and install.
Infit technology offers enhanced fire-performancebecause when the insulation is exposed to fire, it
transforms from a flexible, plastic covering to a tough
insulating ceramic layer, hardening like clay in a potters
oven to form a protective shield. The key to the success of
the new insulation has been in using advanced materials
and polymer science to optimize the nanostructure of the
primary insulation materials. A combination has been
found that reduces the occurrence of cracks or breaks in
the insulation to preserve the operational integrity of the
circuit i.e. preventing short-circuits.
Extensive laboratory tests have shown that cables with
Infit insulation will to continue to deliver power in the
event of a fire, long after the plastic sheath and insulation
have burnt away. This means, for example, exit lighting,
smoke and heat exhaust ventilators, fans or pumps will
still function reliably, even in areas directly affected by fire,
ensuring safe evacuation.
The science partThe new technology is the result of some ten years of
development by the Nexans International Research Centre
based in Lyon, France, working in close partnership with
the Australian Nexans R&D Centre. The successful
outcome of the project has been based on fundamental
studies that especially highlight the synergy betweenceramic science and the latest polymer science.
In classic ceramic science, a well defined curing process
is followed to form a high performance ceramic. Yet, in
BY ARNAUDPIECHACZYK,R&D GROUP
LEADER, NEXANSINTERNATIONAL
RESEARCHCENTER
Infit technology improves
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the case of accidental fire, the temperature increase is
sudden and unmanaged. So the first challenge was to
develop a ceramic forming system able to react and form
an electrical insulating shield in a very short time across a
wide range of temperature increases, while also exhibiting a
high level of electrical insulation.
The second parallel challenge was to achieve this
performance using an extrudable formulated polymeric
material, rather than a powder, that was also suitable for thevery demanding standards of the cable industry. As a result,
Infit technology is principally based on filled copolymers of
polyolefins (like polyethylene). This kind of polymeric matrix
is well adapted to the extrusion process, and well known in
the cable industry - but it is also intrinsically highly
combustible. However, Infit uses the synergy between this
combustible matrix and a mixture of inorganic fillers to
create a new insulating material that offers superior fire-
performance.
Infit applicationsDepending on the specific cable application, the new
insulation material can be offered in either a cross-linked or
thermoplastic version. This will enable cables to offer the
ideal combination of fire, mechanical, electrical or thermal
properties optimized for each application.
Infit is a proprietary Nexans technology, and can be
implemented in compliance with many worldwide cable
standards, and according to the most rigorous productquality and safety criteria. Nexans cables insulated with Infit
can, for example, resist fires reaching temperatures of
around 1,000C, at voltages up to 1kV, exhibiting a high
level of char cohesion and electrical insulation.
Infit is gradually being deployed across the Nexans fire
resistant product ranges. This will include power,
communications, control and LAN cables for use in public
building and industrial applications and it is expected to be
of particular interest to the marine sector.
electrical
cable FIRE SAFETY
POWER CABLES
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POWER CABLES
A CABLE in good condition and installed correctly can last
a lifetime well over 30 years. However, cables can beeasily damaged by incorrect installation or poorly
executed jointing, while subsequent third party damage
by civils works such as trenching or curb edging is also
another main cause of damage.
Service engineers are usually equipped with a suite of
test equipment that enables them to perform an
immediate on site check on the
key network elements of
switchgear, transformers and
cables. If the fault is identified
in a cable, as it often is, and the
network is interconnected, theyare then able to sectionalise the
problem circuit to restore
power to as much of the
network as possible, bringing in
additional generation if
necessary. The next task is to
locate the position of the
underground cable fault as
accurately as possible, since this
makes it easier to find and repair so that the full network
can be restored quickly.
ABB has developed a fault location regime that has
proved very accurate in locating underground cable
faults in both modern XLPE type cables and older
PILCSWA (paper insulated lead covered steel wire
armoured) designs. Fault location is usually carried out
on cable networks up to 11 kV, however the techniques
can be applied on cables up to 33 kV.
The main technique employed is the SIM (secondary
impulse method) that combines the use of classic high
voltage surge generator thumping with low voltage TDR
(time domain reflectometry). To see how this works, it is
useful to consider the merits of the individual techniques.
Cable thumpingThe high voltage surge generator, or thumper, is a
portable device that is used to inject a high voltage DC
pulse (typically up to 30 kV) at the surface termination of
the cable to be tested. If the voltage is high enough to
cause the underground fault to break down it creates anarc, resulting in a characteristic thumping sound at the
exact location of the fault.
Historically, fault location was carried out by various
measuring techniques and by setting the surge generator
to thump repeatedly, and then walking the cable route
until the thump could be heard. At which point x would
mark the spot to start digging. Naturally, the higher the
DC voltage applied the louder the resulting thump and
the easier it becomes to find the fault. If the cable is long
it could take days to locate a fault by this method. During
which time the cable is exposed to potentially damaging
high voltage thumping. So while the existing fault mightbe located, other areas of the cable could have been
weakened in the process. Statistically, cables that have
been thumped tend to fail sooner than would otherwise
have been expected.
TDRTDR (time domain reflectometry) uses a pulse echo range
finding technique, similar to that used by sonar systems,
to measure the distance to changes in the cable structure.
It works by transmitting short duration low voltage (up to
50 V) pulses at a high repetition rate into the cable and
measuring the time taken for them to reflect back from
areas where the cable has low impedance, such as at a
fault. The reflections are traced on a graphical display
with amplitude on the y-axis and elapsed time, which
can be related to the distance to the position of the fault,
on the x-axis.
A cable in perfect condition will not cause any
reflections until the very end, when the pulse encounters
an open circuit (high impedance) that results in a high
amplitude upward deflection on the trace. If the cable
end is grounded ie a short circuit, the trace will show a
high amplitude negative deflection.
Low voltage TDR works very well for the location of
open circuit faults and conductor-to conductor shorts.However, for shielded power cables, it becomes very
difficult to distinguish faults with a resistance higher than
20 ohms. Unfortunately, the majority of faults in
WHEN A POWER SERVICE ENGINEER IS CALLED OUT TO DEAL WITH A LOSS OF SUPPLY ON A
CUSTOMERS HV DISTRIBUTION NETWORK, THE CHANCES ARE IT WILL BE TRACED TO A FAULTY
UNDERGROUND CABLE THAT HAS CAUSED A DEVICE SUCH AS A CIRCUIT BREAKER TO
OPERATE AND CUT-OFF THE POWER. DANNY OTOOLE, ABB POWER SERVICE, EXPLAINS
SIMply the best for locatingUNDERGROUND cable faults
The higher the DC
voltage applied
the louder the
resulting thump,
and the easier it
becomes to findthe fault
The surge
generator used as
part of the SIM
fault location
technique
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POWER CABLES
underground distribution cables are high resistance
faults in the area of thousands of ohms or even
megaohms.
SIMThe SIM (secondary impulse method) technique
combines low voltage TDR and a thumper in an
integrated system that makes the trace easier to
interpret, with a clear indication of the fault location on
a handheld display.
The process starts by running a TDR test on a healthy
core, this is then stored in the SIM system memory. The
thumper is then triggered to send a single HV pulse, and
while the arc is forming at the fault the TDR sends a
further low voltage pulse. The arc acts as a very low
impedance point that
causes the pulse to
reflect in exactly the
same way that it would
from a short circuit. Thehandheld display
combines the two traces
and the fault location is
shown as a large
negative dip, with its
distance easily read off
on the x-axis.
SIM enables a fault to
be located to within a
few metres, even over
very long cable runs of several kilometres. Of course,
underground cables do not always take the shortest ormost direct route between two points, so it is important
to have access to the site cable records. In cases where a
map of the cable route is not available a radio-detection
system can be used to find the cable, but this could add
a considerable amount of time to the exercise. ABB
would always advise customers to make a detailed
record of their underground cable circuits a priority in
their maintenance planning.
Once the target area above ground has been
identified, the surge generator is turned on to start
thumping the cable. The operator then listens for the
thump to home in on the precise location of the fault
this approach minimises the amount of time that the
cable is thumped, eliminating the risk of further damage.
The next step is to bring in the repair team to dig up the
cable, make a visual confirmation of the problem and
then effect a repair.
The time taken to locate a fault by SIM varies
according to each case, but will typically take around
half a day.
Fast track fault location for Silverstone CircuitSilverstone Circuit, located on the border between
Northants and Buckinghamshire, has its own high
voltage power network comprising 17 11kV/433V
substations that provide local power supplies at key
points around the three-mile track. ABB has a long-
standing service contract for the network to provideongoing maintenance and repair services including a
fast call-out response in the event of a fault.
At 6am on 1 July 2008 the ABB duty stand-by
engineer fielded an emergency call saying that there
was a major outage, with a total loss of power to half
the site. In normal circumstances this would be a cause
for concern. With the British Grand Prix taking place on
the Sunday and hospitality organisers and traders
already setting up on site, the loss of power threatened
to cause significant disruption.
Within an hour, an engineer was on site. After
establishing the fault was on Silverstones own networkthey opened discussions with Central Networks, the local
DNO (distribution network operator) to organise
reinstatement of supply. A thorough test and inspection
showed the problem was not due to faulty switchgear,
but was cable related. So ABBs specialised cable fault
location vehicle was called to the site together with
spare cable and joints.
While waiting for the fault location vehicle, the fault
was successfully sectionalised so that it was isolated
from the rest of the network, ensuring it couldnt cause
any further loss of power. This step enabled Central
Networks to restore full power to the rest of the site at
around 9.00am.
The fault location vehicle arrived at 10am, and in less
than two hours the cable fault was located to an area
beneath the tarmac base under a hospitality marquee
erected for the F1 Paddock Club.
The next stage was to expose the identified section of
cable for a visual verification of the damage. A further
10m of trench was then exposed to enable a new
section of cable to be jointed into place. By 10pm, the
jointing operation was finished, pressure tested,
energised and phasing proved so that power could be
restored to this local section of the network. All that
remained was for the trench to be backfilled andrecovered by tarmac. So what might have caused very
severe disruption in Silverstones busiest week of the
year effectively became a minor incident.
14 Electrical Review August 2010
Top: Listening equipment is used tolocate the thump that indicates theprecise position of the cable faultafter the SIM technique has guidedthe service engineer to the generalarea
Bottom: Silverstone Circuit wherecable fault location helped find andrepair a major outage in the run upto the British Grand Prix
The graph shows a typical SIM trace. The dip indicates the location of the fault that can be read off
on the x-axis as the distance from the end of the cable
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ARC FLASH
AN ARC FLASH can be hotter than the surface of thesun. Typically, the arc flash is triggered, for example,
when a short circuit occurs in electrical switch gear,
often during maintenance work. An arc flash can
only occur if the fault
current is very high
several tens of
thousands amps. The
massive energy
released in the fault
instantly vaporises the
metal conductors
involved, blastingmolten metal and
expanding plasma
outward with extreme
force. In addition to
the explosive blasts of
such a fault, much of
the deconstruction
arises from the intense
radiant heat produced
by the arc.
Everybody
knows artificial
electrical arcs
from arc welding
physically seen
an arc flash isthe same but with magnitudes of higher intensity.
The metal plasma arc produces tremendous amounts
of light energy from far infrared to ultraviolet.
Surfaces of nearby people and objects absorb thisenergy and are instantly heated to vaporising
temperatures. The effects of this can be seen on
adjacent walls and equipment; they are often
ablated and eroded from the radiant effects.
Globally accepted studies with regard to the
distribution of thermal injuries have shown apart
from the hands, the head and face are top of the list
of this concerning ranking.
Plastic shields manufactured from polycarbonate,
propionate or acetate providing sufficient thickness
can protect against:
LConventional heat (the plasma heat ball)
L Fragments (primarily or secondarily released by
the explosion)
L Molten particles (e.g. from electrodes, arc feet)
However they are designed to let electromagnetic
radiation pass through. With ultra-violet filters (UV
blocker) a part of this tremendous energy can be
absorbed but scientific findings have proved that this
is by far not enough. The intensity of visible light is
high enough too irreversibly injure human eyes and
the infra-red (IR) radiation can burn eyes and skin.
For optimal protection we need an intelligent face
protection providing:
L Contrast enhancement
L High visible light transmission (up to VLT 70%)
L True colour impression for a broad range of visi-
ble light. Under normal circumstances the highest
possible absorption of radiation from UV to IR.
By using the innovative process of ablation the
proprietary ablative materials absorb the arc flashs
energy layer by layer through a controlled
dissociation process and make the Arc Shield give
up its surface. Subsequently, Paulson improved this
protection mechanism by using nanotechnology; a
further significant milestone following years of
intensive research and testing.
For further information visit
www.arcflashprotect ion.co.uk
AN ARC FLASH OR ARC BLAST INCIDENT IS A KIND OF LIGHTNING IN AN ELECTRICAL CIRCUIT
THAT RESULTS FROM A FAULT IN A HIGH CURRENT ELECTRICAL SYSTEM, REGARDLESS
WHETHER THIS IS A LOW, MEDIUM, OR HIGH VOLTAGE SYSTEM. THE LIGHTNING COMES
FROM IONIZED DAS, SO CALLED PLASMA, EXPLAINS CHRIS ROSS OF J&K ROSS
Protection of eyes and facefrom ARC FLASH injury
Do we really understand this?
CaptionCaption
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ARC FLASH
It is not sufficient to
decide to work live
and then devise
preventative or
protection measures
Note the relationship between
assessment and decisions is
interdependent
18 Electrical Review August 2010
FROM MY EXPERIENCE, I believe Regulation 14 from the
Electricity at Work Regulations 1989, referring to live
working, is often misunderstood and sometimes
overlooked. The duty holder is asked to apply a rigorous
test of reasonableness in allowing live work to proceed in
the first place, and to prevent injury by taking suitable
precautions. It must be stressed that Regulation 14
requirements are absolute which means it must be met
regardless of cost or any other consideration. With this in
mind it makes it very important that any live operation
must be subject to a suitable and sufficient risk
assessment.
Regulation 14 - Work on or near live conductorsA person shall not be engaged in any work activity on or
so near any live conductor (other than one suitably
covered with insulating material so as to prevent danger)
that danger may arise unless
(a) it is unreasonable in all circumstances for it to be dead;
and
(b) it is reasonable in all circumstances for him to be at
work on or near it while it is live; and
(c) suitable precautions (including where necessary the
provision of suitable protective equipment) are taken
to prevent injury.
Before we move on, let me highlight a few of the
important words from Regulation 14.
Near. This word debunks the myth live working onlymeans those activities that require the manipulation or the
removal/replacement of live conductors and components.
Live work can also mean live testing and testing for dead.
It can also mean the opening of control panel doors to
undertake visual examinations or undertake non electrical
work near energised equipment. I find that most live
working in industrial and commercial facilities is confined
to testing, inspections and running adjustments.
Suitably. This word completely changes the meaning ofthe opening sentence. I often hear when conductors are
insulated through finger safe shrouding or cable
insulation then live work can proceed with no further
precautions necessary. I can name several examples of
incidents in switchgear which was finger safe or of Form
4 construction. It is the task or activity near live conductors
which will determine whether the insulation is suitable or
not. An armoured and insulated underground cable may
be suitably covered with insulation where its presence is
known and careful location and hand dig techniques are
adopted but would not be suitable using a jack hammer
without safe dig techniques. Finger safe shrouding,
providing it hasnt been removed, may be suitable
insulation for routine testing but may not be suitable for
the task of drawing in of cables into switchgear
enclosures or other similar invasive tasks.
And. Parts a) b) and c) are separated by the word andwhich means there is a legal requirement for all parts of
the regulation to be satisfied before live work can be
permitted.
Danger and Injury. Danger and injury are highlighted inbold and are specifically defined in the guidance
documents referred to in this article. Briefly, danger means
risk of injury, and injury means death or personal injury
from electrical shock, burns or explosion and arcing. Forlive working, danger may be present but injury must be
prevented.
As an electrical duty holder who may be vexed by the
MIKE FRAIN OF ELECTRICAL SAFETY UK, EXAMINES LIVEWORKING ON LOW VOLTAGE SYSTEMS IN INDUSTRIAL ANDCOMMERCIAL FACILITIES; DETAILING A METHODICAL PROCESSFOR IDENTIFYING THE RISKS ASSOCIATED WITH LIVEWORKING AND THE METHODS FOR CONTROLLING THEM.
Methodical process for risk
IDENTIFICATION
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questions posed in regulation 14 where do you look for
help? Firstly there is the Memorandum of Guidance (HSR
25) published by the HSE. This is usually purchased
instead of a separate copy of the actual regulations, to
assist with the interpretation of each of the regulations in
turn. In addition there is the guidance booklet HSG85
Electricity at Work Safe Working Practices, also available
from HSE Books. Further guidance can be obtained from
the HSE website www.hse.gov.uk.I find HSG85 Electricity at Work Safe Working
Practices is particularly helpful in the decision making
process for working live or dead. Simple flowcharts are a
feature of this document and one such flowchart is
shown below.
It is not my intention to repeat verbatim the advice
given in the existing guidance notes but to further expand
on this decision making process and to emphasise a
methodical process for identifying the risks and the
methods for controlling them. I have used the following
model many times with duty holders to explain the
relationship between the live/dead working decision, task,identification and quantification of the hazard and
preventative measures to be taken. As can be seen, this
relationship is an interdependent one. It is not sufficient
to decide firstly to work live and then devise preventative
or protection measures.
To further clarify this relationship, a decision for work to
proceed cannot be taken in isolation to other factors. The
level of hazard and also the availability and effectiveness
of preventative or protective measures will also need to
be considered. This is all directly affected by the work
task.
Steps to Identify and Assess the Risks and Methodsfor Controlling them.The live working decision flow chart Figure 1 illustrates that
a critical part of decision making is the identification of risks
and the methods for controlling them. I find it useful to
break this down into a four step process as follows.
STEP 1: Equipment and shock hazard
STEP 2: Electrical flashover
STEP 3: People and safe systems of work
STEP 4: Environment
Fig 1. Diagram reproduced
from HSG85 Electricity at
Work - Safe Working
Practices under PSI license
no C2010000923
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ARC FLASH
STEP 1 Equipment and shock hazardHas the equipment been checked and is it in a safecondition? Check whether the equipment to be workedupon has been examined and in a safe condition for
work. Live work should never be permitted where there
are any doubts about the safety of cables and electrical
equipment being worked upon or even adjacent to those
being worked upon. The examination can be visual but
also using other senses such as smell and hearing to
detect burning or electrical discharge.
Signs of vermin or birds inside switchgear or water
ingress is a definite prompt to stop and investigate only
when the switchgear is dead and isolated. Approaches
should never be made to cables damaged by site traffic or
excavation.
Is the equipment finger safe? If the equipment is in asafe condition the next step is to consider whether the
equipment is finger safe. If the equipment is not finger
safe, can measures such as temporary shrouding be used
to prevent contact with live parts? The term finger safe isdefined as no exposed live parts that can be accessed by
solid objects greater than 12.5mm as given by IP rating
IP2X.
Do not rely purely on the original specification of the
equipment. Insulation is often removed and not replaced.
If it is not finger safe, or other measures cannot be
introduced to prevent contact with live parts then carry
out the work dead.
Are tools, instruments and leads checked fit forpurpose? If measures to prevent contact with live partscan be implemented, are tools, instruments and leads
checked fit for purpose? Tools and instruments must beof the correct duty rating and their condition must be
checked especially test leads. It is important correct
instruments and leads should be selected and in
particular the correct over voltage installation category in
accordance with EN61010-1. The wrong meter and leads
can increase the chances of electric shock or the initiation
of an electrical flashover due to transient over voltage.
Most instrument manufacturers publish guidance about
overvoltage on their websites.
Are you sure the equipment is designed for live
operation? There seems to be some opinion that because
electrical components plug in then this operation can be
carried out live. Examples of such components are plug in
circuit breakers or bus bar trunking tap off units. Always
contact the equipment manufacturer if such a live
operation is contemplated. You may find the equipment
has been designed for flexibility rather than for live
operation and the manufacturer may discourage such
activities.
STEP 2 Electrical flashover or arc flashIs there a significant risk of burns from electricalflashover? I have authored several articles on the subjectof electrical flashover in Electrical Reviewand they can be
accessed at www.electricalreview.co.uk. In brief, theseverity of the thermal effects of an electrical arcing event
is usually expressed in units of calories per square
centimetre at the working distance from a potential arc
source and the head and torso of the worker. This is called
incident energy and a level of 1.2 cal/cm2 is sufficient to
predict a 50% chance of the onset of a second degree
burn.
Incident energy has an approximate linear relationship
firstly; to the amount of current that can flow in the arc
and secondly to the time that it can flow before the
upstream protective device clears the fault. Note that
arcing current does not equal prospective fault current
(PFC) and at 400 volts is likely to be less than 50% of PFC.
It follows the upstream device may take longer to operate
with resulting higher levels of incident energy. Keep in
mind also, protective devices need to be maintained to
ensure they will operate according to their time current
characteristic.
When undertaking arc flash studies for industrial and
commercial facilities, I have found, where the upstream
protective device is a conventional fuse or fast acting
fixed pattern circuit breaker at a rating less than 100
amperes and the voltage is at 400 volts 3 phase andbelow, then the incident energy levels will be limited. A
rule of thumb is to use the good old BS88 Industrial
fuse as a model. If the entire time/current characteristic
curve of the upstream device can sit below a BS88 100
ampere characteristic curve, the incident energy at a
working distance of 450mm is unlikely to exceed
1.2cal/cm2. This does not mean flash burn injury can be
totally discounted and severe burns can still be
experienced particularly at the hands which will usually
be closer any arc initiated when testing live circuits. For
comparison, a BS88 400 ampere fuse could present a
predicted *20 cal/cm2 at certain fault levels and an 800ampere fuse could be in excess of *60cal/cm2.
*Note these figures are for indicative purposes only, not
to be used in a risk assessment.
Suitable risk control measures must be employed and
as a last resort PPE should always be used. In the case
of the 800 ampere fuse, PPE is unlikely to fully protect
the worker because of the possible ballistic and other
effects of a flashover. Regardless of tasks, I recommend
electrical workers should not carry out work in high
power environments in clothing that can ignite or melt.
If the incident energy at the equipment to be worked
on is over 1.2 cal/cm2, then can it be reduced to below
1.2 cal/cm2? As an alternative, can risk controls be put
in place to prevent or mitigate arc flash effects and are
they adequate? Please refer to my recent articles,
available on the Electrical Review web site. If the
answer is no to both questions then proceed no further
until advice is sought or carry out the work dead.
STEP 3 People and safe systems of workAre the workers competent for the task? Regulation 16from the EAW Regulations 1989 states: A person shall not
be engaged in any work activity where technical
knowledge or experience is necessary to prevent danger
or, where appropriate, injury, unless he possesses suchknowledge or experience, or is under such degree of
supervision as may be appropriate for that purpose
having regard to the nature of the work.
Do not rely purely on
the original
specification of the
equipment. Insulation
is often removed andnot replaced
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In the context of live work, technical knowledge or
experience means the person should be properly trained
and assessed in the techniques being employed but the
person must also understand the hazards from the
electrical system and be able to recognise whether it is
safe for the work to continue at all times including whilst
the work is being carried out.
Is the work to be carried out at height? Working on liveequipment at height is always a special case for
consideration for two reasons:
1. Electric shock or arc flash to a worker at height can
bring about a fall with obvious consequences.
2. An arc flash incident whilst working at height may
mean that the worker cannot move out of the way
because of the limited working space on access
equipment. This may be the work platform of a scaffold
or a mobile elevated work platform.
If the work has to be carried out at height, can risk
control measures to prevent shock, burns and falls be put
in place?Is Accompaniment Required? Anyone undertakingwork on or near energised electrical conductors will nearly
always require some form of accompaniment by someone
who can give assistance in an emergency. This implies a
degree of competence such that the accompanying
person can assist without danger to themselves or others.
A requirement for a second person is to ensure safe
working procedures e.g. preventing encroachment of non-
authorised personnel into the working area.
STEP 4 Environment
Is access and space adequate? Establish whether theaccess and space in front of the equipment is adequate to
allow the worker to pull back from the conductors without
hazard. HSG85 mentions a minimum 915mm measured
from a live part or 1375mm when there are live parts
exposed on both sides of the worker. The working space
may need to be greater than these minimum distances as
a result of the electrical flashover assessment in Step 2.
The work area should be clearly defined, with no
tripping and slipping hazards and with good means of
escape and illumination. Simple barriers and signs can
often be erected for the demarcation of work areas to
keep non-authorised staff away and also to protect
electrical workers from interruptions at times when they
need concentration.
Is lighting adequate? It is also important to checkwhether lighting levels are adequate for work as well as
another requirement in Regulation 15. Use of additional
lighting is essential where ambient lighting levels are
poor.
Are hazardous conditionspresent? Check to ensure theimmediate environment is free
from water or dust. A hostile or
wet environment will
significantly increase the risk and
severity of electric shock and
should therefore be subject of
special consideration to controlthe risks. Ensuring there is no
possibility of an ignition hazard
due to sparks is crucial. If there is
a possibility of an ignition
hazard, take precautions to
remove the hazard before
proceeding. There may other
local environmental hazards that
may need to be taken into
account such as automatic fire
fighting equipment.
Proceeding with workAfter all 4 steps are satisfied, then revisit the flowchart in
Figure 1 and confirm the work is justified relative to the
precautions, implement safe working and ensure
adequate monitoring and supervision. Make sure any
special equipment and PPE is properly used and
maintained and always keep the duration of any live work
to a minimum.
www.electricalreview.co.uk 21
Recommended Further Reading
HSR25 Memorandum of Guidance on the Electricityat Work Regulations 1989 (HSE books)
HSG85 Electricity at Work - Safe Working Practices(HSE books)
INDG163REV2 Five Steps to Risk Assessment (HSEbooks)
INDG 354 Safety in Electrical Testing at Work (HSEbooks)
GS38 Electrical Test Equipment for use by Electri-cians (HSE books)
Guidance on Safe Isolation Procedures for LowVoltage Installations (Electrical Safety Council)
HSG230 Keeping Electrical Switchgear Safe (HSEBooks)
ARC FLASH
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UPSsolution for bridge power.
The very high cycle life of a SuperCaps UPS means
unlike lead acid batteries, there will likely be little or no
need for constant replacement. The facility to repeatedly
charge and discharge for up to a million cycles without
disintegrating, means the lifetime cost of the SuperCap is
expected to break even with lead acid batteries.
Longevity is helped by the fact their high power density
results in reduced strain on the battery in times of need.
Another major consideration is the fact the SuperCap also
has the ability to recharge instantaneously, in a few seconds.
This is really useful in data centres, to help cut power costs
associated with keeping batteries charged.
Another important factor is the ability of SuperCaps to
offer versatile functioning in a wide temperature range,
dramatically reducing cooling costs. This is because the
function of a SuperCap does not require a chemical
reaction, and therefore, does not involve an optimal
temperature range for best performance or longevity.
It has been estimated the supercap can be used from -
40C to +70C, without degradation in its performancecharacteristics. This is in stark contrast to the lead-acid
battery, which when used in industrial applications, almost
always requires a mechanically cooled environment.
Pros and ConsThe SuperCap is green in two ways. Firstly, it reduces waste
because it has a very high cycle life, and therefore decreases
disposal issues. Secondly, the materials and substances used
in the SuperCap UPS are toxin free and biodegradable, e.g.,
nano carbon particles are commonly used. They can operate
in a wide temperature range without any degradation of
performance characteristics, and it also has the ability torecharge instantaneously in a few seconds.
SuperCaps are ideal energy storage devices for fast and
short-term peak power delivery, which is why they are so
suited for UPS systems. They are also more efficient than
conventional batteries as they do not release any thermal
heat during discharge, and various figures have shown that
they operate at around 80% - 95% efficiency in most
applications.
SuperCaps also take up much less room compared to
lead-acid batteries, and indeed weigh less as well, which
can be an important factor in certain situations or locations.
The table below contrasts the pros and cons of SuperCaps
with traditional UPS technology.
ConclusionThere is no doubt the industrial market needs an energy
storage solution that is both reliable, and can offer a quality
service. SuperCaps offer high power density, cycle life, and
thermal susceptibility, and the increasing adoption of
renewable energy expands the possibilities of using
SuperCap-based technology.
Frost and Sullivan points out the total world
ultracapacitor (SuperCap) market had generated revenues
of $113.1m (75m) in 2008 and is likely to reach $381.9(250m) by 2015. It feels this market has witnessed growth
(despite the economic situation) due to the great interest in
propelling alternative energy storage mechanisms by
governments. Indeed, Europe has given the highest priority
to any environmentally friendly technology and has a
proud tradition of being one of the first global markets to
accept new technology and consider its applicability in
various solutions.
The high price of oil, coupled with high electricity costs,
the need for devices that can reduce the power burden of
a data centre represents a significant opportunity. The
increasing use of supercap technology within thetransportation industry will also serve to spur new
developments and help drive down the initial cost of
ownership.
24 Electrical Review August 2010
Pro
A SuperCaps UPS is green and does not contain toxic materials
Can operate in a wide temperature range, without a degradation in its
performance characteristics
Do not release any thermal heat during discharge
A SuperCaps UPS is much more efficient than a conventional battery
Ideal energy storage device for fast and short-term peak power delivery, for
indefinite cycles.
Up to 20 years lifespan
Reduced footprint compared to lead-acid batteries, and also weighs less
Scalable-modular nature that make it well suited for many applications
A SuperCaps UPS, used strictly as a bridge, has high power density that is well
suited to supply high power for short periods of say around 30-100 seconds
Flexible voltage range
A SuperCaps UPS is inherently reliable because of its composition and construction.
There are no mechanical moving parts, eliminating maintenance
Capable of sitting on a charge voltage for extended periods without any loss of
capacity, unlike a batteryDevelopment of the technology is being pushed by massive industry heavyweights
in the transportation sector. Honda for example has developed its own supercaps
for its vehicles
Con
Despite their indefinite life cycle, SuperCaps have the ability to provide only very
short-term power
High initial cost of ownership. Supercaps are more expensive than flywheel, as it is
still in its nascent stage of commercialisation
End users are unable to perceive or experience the true advantages of this
technology due to early stages of take-up and lack of awareness
Lack of industry standards to regulate and stimulate full commercialisation of thetechnology. Design time is longer, which results in a longer lead time to get a
product ready for the end user
The SuperCaps UPS is unable currently to store as much energy as a battery
because there are no chemical reactions taking place that can sustain the slow
discharge of current to power equipment
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Pros and Cons of the Supercap UPS(Maxwell Technologies)
The very high life cycle life of aSuperCaps UPS means, unlike leadacid batteries, there will likely beittle or no need for constant
replacement
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PRODUCT WATCH
PROVING UNIT LAUNCHIt is a recommendation of the HSE given in guidance note GS38 that voltage indicators should be proved
before use and after use.The Portable battery powered proving unit PU260 has been introduced by Di-Log to carry out this vital
check function for all makes of two pole voltage testers up to 690 V.In addition to proving the correct functioning and voltage output a voltage tester the PU260 ha a number
of unique features which have not been previously found on this type of unit. Continuity test for testing: fuses, test leads etc
Additional touch electrode for quick testing of fuse leads Optical and acoustic continuity indication Low battery indication LED indication of current output in excess of 3.5 mA Protective rubber holster Supplied with batteries
Di Log Test Equipment0161 877 0322www.dilog.co.uk
TINY DRIVES TAKE VERSATILITY TO THE MAXAdditional EMC filtering options, configurable analogue inputs and enhanced fieldbus connectivity are
among the many new features that have been added to the latest M-Max variable speed drives from Eatonselectrical sector, which are available with ratings up to 7.5kW.
Featuring compact book-style construction and very competitively priced, M-Max drives can be configuredby the user for either V/f or sensorless vector control. This makes them an ideal and cost-effective choice forenergy-saving fan and pump applications, and also for generalindustrial applications where accurate speed control is needed.
A large built-in display and operating unit makes it easy toconfigure the drives and to monitor their performance, while anelectronic setpoint potentiometer facilitates accurate speed setting.
Eaton0161 655 8900
www.eaton.com
POWER SUPPLY AND LINE DIAGNOSTICS ON THE BUSR. Stahl's new Advanced Fieldbus Power Supply (A-FPS) is said to be the first and only power supply
module for Foundation fieldbus H1 segments to addi-tionally provide a wide range of physical layerdiagnosis functions. At a 10% premium over the standard supply module from the same series, theintegrated devices enable complete and continuous plant monitoring.
In the past, the integration into asset management systems requiredseparate, cost-intensive diagnosis modules and software tools. EachAdvanced Fieldbus Power Supply (A-FPS) not only detects overload andshort circuits on its seg-ments, but also continuously registers the physicalparameters of the fieldbus, such as voltage and current on the trunk,
communication level, noise level, asymmetries and jitter.
R Stahl0121 767 6400www.rstahl.co.uk
PROTECT MISSION CRITICAL APPLICATIONSThe PowerGem Pro Series has been upgraded with the latest DSP technology to
provide a new Online Double Conversion range from the British Power ConversionCompany. Available in both tower and rackmount configurations from 1kVA up to10kVA is an advanced True Sinewave design combined with our unique isolationtechnology to give you a UPS with all the flexibility and dependability you need.
These modern, compact UPS have an enviable reputation in providing theultimate in no-break power protection making them ideal for sophisticated
computer networks, as well as telecommunications, industrial, defence, medical and process control equipment.
This new range achieves higher reliability and greater immunity from mains power problems to the connectedload by using a Digital Signal Processor (DSP). The front LCD panel display provides real time status andparameter readings allowing simple operation and a full diagnosis for easy servicing.
BPC EMEA01794 521200www.bpc-ups.com
PRE-TERMINATED MULTI-FIBRE TRUNK CABLEASSEMBLIES
Now available from the Amp Netconnectbusiness unit of Tyco Electronics is a range ofmulti-fibre trunk cable assemblies in avariety of configurations.
The new cables are factory terminatedand tested in custom length options up to500 m initially available with 12 fibres asOM3 multi-mode and OS2 single-modeversions and a choice of LC-LC or SC-SCconnectors. They can be used as pre-
terminated links for quick deployment or cutin half to create fibre harness links.
Each cable ends in a staggered fan-outassembly with 2 mm buffered tubes withprotective tube over the connectors. Cable
jacket features internal and external ULSZH(Universal Low Smoke Zero Halogen)construction.
Tyco Electronics UK020 8420 8130www.tycoelectronics.com
SUPPORT FOR SAFETY- RELATEDMACHINE CONTROL
Designed to provide developers and testers ofsafety-related machine controls with comprehensivesupport in the evaluation of safety in the context of ENISO 13849-1, Sistema software is available fordownload on www.wielandsafety.net. Sistema standsfor safety integrity software tool for the evaluation ofmachine applications and enables users to model thestructure of the safety-related control componentsbased upon the designated architectures. This, in turn,allows automated calculation of the reliability valueswith various levels of detail, including that of theattained performance level (PL).
Relevant parameters such as the risk parameters fordetermining the required performance level (PLr), thecategory, measures against common-cause failures(CCFs) on multi-channel systems, the averagecomponent quality (MTTFd) and the average faultdetection level (DCavg) of components and blocks, areentered step by step in forms. Once the required datahave been entered into Sistema, the results arecalculated and displayed instantly.
Wieland01483 531213www.wieland-electric.com
Products continued on p28
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BUILDING SERVICES
26 Electrical Review August 2010
THE SECTOR faces the twin challenges of riding out the
toughest recession in living memory, and delivering new or
refurbished buildings which consume less energy and emit
less carbon. Much of that carbon is emitted by electrical
systems, so the electrical services sector is at the forefront
of the drive to improve our building stock.
With the latest revisions to Part L of the Building
Regulations coming into force in October 2010, and with
the recently introduced Carbon Reduction Commitment in
place, developers and building owners will have to allocate
more resources to adapting their buildings for future
climate changes.
The current cost of adaptation, using some technologies
that are not 100% tested and proven, is not considered to
offer a fast enough payback, and in many cases is seen as
relatively expensive in offsetting the short-term cost of
carbon emissions. Several adaptation technologies such as
photovoltaic, on-shore wind farms, hydro and wave power,
demand large open spaces, or require planning
permissions, or both, which can be hard to obtain. There is
a growing conflict between the desire of government to
cut carbon emissions and invest in renewable, and the
willingness of planners to sanction them.Whilst some building integrated low or zero carbon
technologies are well established, such as solar thermal
water heating, photovoltaics, or heat pumps, they may
require substantial upfront capital investments. There are
only a handful of exemplar projects provided by the
Carbon Trust and Energy Saving Trust to demonstrate real
life energy and carbon emissions reduction. The
Technology Strategy Board is funding a number of further
projects in this area to demonstrate how buildings can be
adapted to meet the requirements of our anticipated
future climate, but these will take time to influence and to
stimulate investments by the private sector.
The introduction of the Feed in Tariff provides some
incentives to install renewable technology, with the
prospect of ongoing revenue to encourage initial capital
outlay. The tariff came in in April, and it is too early to see
how much of an impact it is having on demand. There are
therefore a number of measures which can be expected to
stimulate demand for electrical services, but not in the
immediate future. Whether this demand will materialise intime to support the sector through the current period of
reduced workload remains to be seen.
What we ought to see at this time, with the prospect of
IN MARCH 2010, THE TIMESREPORTED UK CONTRACTORSGROUPS OUTLOOK FOR THENEXT FEW YEARS IS DEEP PUBLICSPENDING CUTS WILL LEAD TO
SOARING UNEMPLOYMENT INTHE CONSTRUCTION INDUSTRY.AT THE SAME TIME, THE UKFACES CHALLENGING CARBONEMISSIONS REDUCTION TARGETSBETWEEN NOW AND 2050,WHICH COULD BE JEOPARDISEDBY THE LOSS OF KEY SKILLS
FROM THE SECTOR EXPLAINSTONY SUNG, CHAIRMAN OFCIBSE GROUP AND TECHNICALDIRECTOR AT HYWEL DAVIES
New skills for new
OPPORTUNITIES?
Tony Sung
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steadily increasing demand for energy efficient
refurbishment and renewable technologies, is increasing
training to meet the emerging demand for these skills. But at
present training in the sector is falling, as firms, many of
them SMEs, cut back on all non essential spending to
conserve cash and protect the business.
One of the measures introduced in response to the
Climate Change Act is the Carbon Reduction Commitment
Energy Efficiency Scheme, or CRC. This started in April 2010,
with the primary objective of helping medium to large size
organizations whose total half hourly electricity consumption
exceeds 6,000MWh, to cut their energy use and carbon
emissions. To enable the For CRC to be a success, Britain
needs to up-skill the current M&E workforce (electricians,
design and installation engineers) competently to apply,
install, test and commission the low zero carbon and smart
metering technologies in tens of thousands of existing
buildings rather than just for new buildings.
Again, looking at the figures for compliance with the
requirement for Energy Performance Certificates, Display
Energy Certificates and Air Conditioning Inspections, we should
be cautious about the prospects of CRC stimulating a wholenew wave of activity in the current economic conditions.
Another area of development is the new amended
BS7671:2010, currently issued in draft for public comments.
This includes vital changes necessary to maintain technical
alignment with Cenelec harmonisation documents. One of
the perceived advantages of the technical alignment is it
should help British companies to win work in the EU.
Cibse, through its Electrical Services Group, provides
electrical services engineers with a network of like minded
professionals who are active in all of these areas. Through
Group events and through the website, http://www.cibse-
electricalservicesgroup.co.uk members can access the
collective knowledge and expertise of the group.
Additionally, Cibse runs a number of events and training
courses for electrical services engineers, and recently
launched a new web based learning initiative, to provide
training in electrical services (and other building services
disciplines) that is flexible and adaptable to user needs. Cibse
and the Electrical Contractors Association recently signed a
Memorandum of Understanding, which commits both
bodies to work together more closely to help develop and
deliver electrical skills and services, to better meet the
challenges of climate change.
If we are to meet the carbon emissions reduction targets
for 2030 and 2050, we will need to see greater investment,both in new technologies and in skills. Cibse will be looking
to work with engineers and employers in the sector to
deliver both.
BUILDING SERVICES
Image courtesy of Shutterstock
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PRODUCT WATCH
AC DRIVE CONTROLLEDSCROLL COMPRESSORIMPROVES EFFICIENCY
A chiller unit utilising a scroll compressor is setto generate 15% lower energy consumption thanmodels with a traditional compressor design.
The unit has been produced by air conditioningmanufacturer Rhoss, using an ABB standard drive.
Scroll compressors pressurise the refrigerant between two interleaved spirals or scrolls,resulting in a design with fewer moving parts, less noise and reduced vibrations comparedto other compressor types. Variation of output is traditionally provided by mechanicalmeans, for instance by splitting the cooling capacity of the chiller into several circuits.However, by using the ABB standard drive, Rhoss has achieved better performance whileusing a simple design with a single circuit.
ABB01925 741 111www.abb.co.uk/energy
ETHERNET SWITCH WITH FAST TACK
SWITCHING TECHNOLOGYThe Ha-VIS FTS 3100s-A is the first switch in the HARTING
family of industrial Ethernet switches to offer the companysinnovative Fast Track Switching technology: a solution thatsatisfies the majority of perf