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ilp archive : journals
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public lighting no. 45 vol. 12
April-June 1947
- Editorial p9
- Lighting Restrictions p9
- Whilst many engineerings must have wished for a full resumption of pre-war street lighting,
the order now issued to local authorities by the Minister of Transport, makes it clear that a good
standard of street lighting will be made available to the public after August 10th, at the
end of double summer-time. To save 50% of public lighting, the engineer is free to adopt his
own particular methods. They can "turn off" lights at midnight or reduce side street lighting,
providing always the result is the same - to save 50%.
- Lighting: Energy, Lighting: Legal
- Good Main Road Lighting p9
- One detail should be kept in mind - the main traffic routes need to be well lighted, and
if possible, left alight thoroughout the hours of darkness. It is difficult to reconcile
that it is so important a public service as street lighting should be penalised to such an
extent, in order to save, for the whole country, a mere 200,000 tons of coal per annum. To
give the public all the night lighting they need, it means a total annual fuel consumption of
only 400,000 tons of coal - less than 1% of the total fuel output of the country - it is
hard to understand the reasoning of those in authority. May hten time be not too far
distant when all talk of a 50% reduction shall be a thing of the past.
- Lighting: Energy, Lighting: Legal
- A.P.L.E. Deputation to M.O.T. p9
- Appointed by the Council of the Association, the deputation expressed to the Minister
the considered views of the Association in: matters relating to restrictions in street lighting;
the need for improved standards; greater uniformity and consideration of the financial
needs of smaller authorities (required to light traffic routes in their area). The Minister
has acted as far as possible on some of these recommendations, and has embodied them in his
latest circular to local authorities.
- Lighting: Authority Organisation, Lighting: Energy, Lighting: Legal, Lighting: Specifications
- The Southport Conference p9
- Arrangements are well advanced for the next conference which is to be held
at Southport in September (15th-19th). Street lighting apparatus and equipment will be
displayed on several of the highways adjacent to the Conference Hall and the lamps will
be lighted each evening. There will be a display of modern street lamp columns, which will
be erected together in the gardens on the seafront. This exhibition of columns is most
appropriate, especially in view of the renewed interest now been taken in street furniture by
the Royal Fine Art Commission. The Secretary of the Commission will be delivering an
address on the subject at the conference.
- APLE: Conference
- The A.P.L.E. Sends a Deputation to the Minister of Transport p10
- In a brief submitted to the Minister before the deputation:
- They expresssed satisfaction that the Department has now become the central authoritiy authorised by H.M. Government to deal with matters
concerning street lighting.
- 1. Existing Street Lighting Restrictions: The existing restrict on street lighting,
issued by the Minister of Fuel and Power, should be withdrawn. It is appreciated that
these restrictions are the results of a request only, and have not been covered by the issue
of a Statutory Rule and Order under the Defence (General) Regulations 1939. No definite indication
has been given as to the method to be adopted in making restrictions, with the result that lighting
authorities have interpreted the request in many different ways, causing considerable inefficiency
of lighting, and confusion to road users. There is no doubt that considerable dissatisfaction
is felt by many lighting authorities as to these suggested restrictions, due to varying
interpretation by adjoining authorities.
- 1. Group "A" Road Lighting: The limitation has altered completely the usefulness
of the scientific siting and arrangement of the lamps and has prodcued dark patches and black
spots to the observer; thus pedestrians and cyclists are under the altered conditions unseen
by motorists.
- 2. Group "B" Road Lighting: The situation is even worse in secondary roads ("Class B") as some lighting authorities
have switched off all street lamps. This is completely wrong and should be officially discouraged.
When motorists leave a well-lighted main road for an unlighted, or semi-lighted, secondary
road, drivers fail to be "dark-adapted" in sufficient time to prevent accidents.
- 3. Policing of Roads: Darkened streets, and in particular Class "B"
(secondary roads) cause considerable additional difficulties for the police. Police from
many authorities have informed the Association that undr present conditions, crime has risen
considerably. A large number of cases of assault is being reported. This is detrimental
to the general well-being of the public and have a tendency to lower still the general morale,
already taxed by long period of war-weariness and stress.
- 4. Saving Of Fuel: Street lighting should not be restricted against the interests of public safety. Returns made
in 1938 showed that the amount of coal used for the full street lighting in the preceeding 12 months was only 0.1% of
the total coal output of the British Isles. It is a small percentage of the full use for domestic purposes and is negligilbe
compared to the cost of increased accidents. Such accidents, apart from the terrible results in death and injury,
result in the loss of working time, damage to property, vehicles etc. A more valuable saving would be obtained by the closing
down of radio transmission at 10PM thus resulting in a direct saving of fuel consumed after that hour in the use of radio,
use of lighting in the home and heating.
- 5. Information To Public: Present restrictions on street lighting have been prompted more by psychological reasons
than by the need for fuel saving, the Government being of the opinion that the public would complain of unrestricted
street lighting while they were restricted in their homes. By means of well-chosen Press announcements, radio talks and
poster appeals, the public would quickly become informed to the definite and increasing need for well-lighted streets in
the interests of road safety, freedom from assault and security against crime.
- 2. Future Ministerial Recommendations Regarding Street Lighting
- We would request that future information as to street lighting restrictions should be given to lighting authorities
and their officials at an early stage. Such early advice is necessary to enable officials to undertake the work involved.
- 3. Revised Procedure
- The assumption by your Department as the central authority in matters connected with street lighting has raised the need
for some clear information and guidance for lighting authorities and their officials in street lighting matters. Such information
would concern:
- 1. The exact spheres of the several Government Departments responsible in relation to the public lighting of England, Wales and
Scotland.
- 2. The exact procedure to be followed by lighting authorities when obtaining Government authority where required for the purchase of
various lighting materials.
- 3. The exact procedure to be followed by lighting authorities obtaining Government authority to borrow money for new installations.
- 4. The exact procedure to be followed by lighting authorities obtaining Government grant towards capital commitment and maintenance.
- 4. Greater Uniformity
- The Association has consistently advocated to members and road engineers, the need for complying with the 1937 MOT Report.
We are anxious that you will give adequate guidance to all lighting authorities on this matter. We recommend the need for
greater co-operation between adjoining lighting authorities, especially between London Boroughs and authorities on the outer London
County.
- 5. Financial Aspect
- It is appreciated that many local authorities with areas of low rateable value, with long lengths of roadways, are unable
to meet the costs involved in providing adequate street lighting and we would urge that some consideration should be given for
revision of the finance of street lighting. We suggest it be considered on lines similar to those originally operating with roadway
provision and maintenance. In the same way, futher consideration should be given to more practical liaison between authorities.
Consideration of the financial aspect would also enable authorities to have the benefit of an official whose duties would be solely
connected with the provision and maintenance of adequate street lighting. Only larger authorities can afford such an official.
- 6. Street Lighting Should Be Compulsory
- Street lighting should not be a permissive service. It is a service which shuld have the full weight of law and should
be a compulsory duty to affected local authorities. Street lighting is compulsory in certain areas of Scotland and the introduction
of similar laws to cover the rest of Great Britain would be appreciated.
- Signed, W. N. C. Clinch, T. Wilkie, E. J Stewart, E. C. Lennox, H. Pryce-Jones
- Lighting: Authority Organisation, Lighting: Energy, Lighting: Funding, Lighting: Legal, Lighting: Safety, Lighting: Specifications
- The American Approach to Public Lighting (Part One) by H. L. Juliusburger, F.I.E.S. p12
- The great variety of nations linked up in the pre-war days on research and appliction problems
in the Street Lighting field have virtually been reduced to a group of two: Great Britain and
the American Continent. And between these two there is one marked different: Paper Shortage.
No fundamental divergency of approach to Street Lighting problems, in a technical sense has been
discovered so far.
- Reasons for the Campaign of Good Street Lighting.
- Street and Highway lighting is discussed at length in the American Press including such
items as Recreation Grounds and Air Terminus Lighting. Contributions are made from all quarters of
the manufacturers' and consumers' world, research engineer, fittings manufacturer, civic official,
traffic safety engineer and professional organisations like the I.E.S. Public discussion is
bearing marks of a nation-wide "mobilisation" of manufacturer and consumer (Municipalities)
foreshadowing action of a magnitude which cannot fail to impress any person
desirous to see good Street Lighting widely recognised as a necessity. Two sets of conditions
appear to have prompted this campaign: Road Traffic Development and the organisation of
Municipal Administration. There is a genuine anxiety underlying this campaign shared by
authorities and professional organisations regarding the safety aspect of road traffic,
and a serious attempt is proposed to bring road accidents under control.
- Traffic Safety Lighting
- L. J. Schrenk, Lighting Superintendent of Detroit, is credited with the first
practical move to demonstrate the relationship between road accidents at night and Road
Lighting, and today he is called the "Father of the Traffic Safety Lighting" idea. The
belief is that adequate street and highway lighting will be the quickest and possibly the
cheapest means to reduce night traffic accidents and economic loss. This has to be put
over to the man who authorises the orders i.e. the Civic Official.
- He is in charge of Road Lighting. He does not have a technical background nor is he employed
on the base of a service agreement. His position is subject to election. Improved street lighting
might mean increased taxes and this is considered a danger to popularity. In justifying
such an expense he requires arguments which are convincing when he has to face the electorate.
A professional body like the A.P.L.E. could do a great deal of good in the USA today. Even
non-member municipalities, and the civic official, would come to look on the A.P.L.E. as
representing his interest and soon appreciate the value of its professional advice. There
seem to be few municipalities in the USA employing the services of a professional man
on a proper contract basis. A campaign is aligned to the motto: "A community pays for
good Highway Lighting whether it actually has it or not.
- Traffic Safety is the main theme, and Traffic Safety Lighting the main objective. The days
when Stret Lighting was provided essentially for decorative purposes are gone, it is only
a by-product of the main endeavour.
- The Facts: Traffic and Accident Records
- The facts i.e. the traffic and accident statistics are a very weighty argument. The fatality
rate in road accidents for the whole country is 7,500 or which only 2,500 occurred during the
day-time. This refers to accident records covering 30,000 miles of "Main Traffic Roads"
for the year 1941. The claim is that effective improvements of street lighting and the
erection of new installations to the required extent could result in the annual saving of
3,000 lives, 100,000 injuries and 450,000 cases of property damage on the Highways alone. As
there was so little action in this field during these years, practically no statistical
records of wider than regional importance are available. In Los Angeles, where the revision
of lighting installations at 25 road intersections resulted in an immediate reduction of
accidents: Night accidents 78%; night fatalities 92%; personal injuries 79%.
- No evaluation system as yet exists to yield direct and adequate answers regarding the
factors governining Street Lighting influence on accident rate. The target should be
to reduce the accident rates at night to an amount qeual to that occurring in daylight. A
Canadian authority expressed the belief that the provision of adequate Road Lighting along
10% of the total length of major traffic arteries will suffice to "make" it.
- A recent survey states that Accident Insurance rates, based on the accident records of
the municipality, are lowest in cities with "plenty of artifical light on the roads."
This can be believed considering the results of the Connecticut statistics, which show a
55% increased of personal injury and property damage during the dim-out. Great efforts have
been made in the Press in the years 1944-1945 to exploit the general psychological reaction
to dim-out conditions not merely in the direction to make everyone appreciative of some form
of light in the road, but to go further and create a desire on the part of the public
to see adequate Street Lighting installed.
- The "Yardstick" for adequate Road Lighting and Expenditure
- What is adequate street lighting. To answer this question everyone turns immediately to
the Recommendations of the I.E.S. However, it is pointed out that these Recommendations are
somewhat tempered by what is expected to be available in the nature of funds - and it is
strongly advocated to exceed the individual values shown in these Recommendations where financial
means permit. But if laymen are the responsible officers then a simplified version is required.
It is proposed to make the values recommended for Light Traffic Thoroughfares the Yardstick for
improvement. These provide for a minimum average illumination of approximately .3 f.c. The average,
operation and maintenance cost of such an installation will ammount to 30-40 cts. per lineal ft. road
length.
- This leads to the importnat question of expense and taxpayer's contribution. The "Municipal Index"
covers statistics of 1036 municupalities with a total population of 46,000,000 and a total of
76,604 miles of road length. The average Lighting Rates per indiviudal tax-payer are assessed at
2.6 dollars on the basis of this proposal. The bigger towns will not have to raise their expenditure
by more than .6 dollars per capita on the average to comply with the new standard, but it is realised
that smaller municipalities will have to step up more drastically.
- In the case of rural Highways the position is different. Here it is suggested to cover operation
and maintenance costs by revenues from petrol taxes and registration fees. In 1941 a sum
of 1,452,011,000 dollars has been received and of that 215,000,000 dollars were divered to non-highway
purposes. About 4% of the total highway mileage is said to require adequate lighting, a length
of approximately 20,000 miles. It is confidentially expected that a budget of 21,000,000 dollars
would cover all respective operation and maintenance cost.
- This publication was made as a reply to an article by F. H. Pulvermacher published in
the Electrical Review on Trunk Road Lighting. It was given close attention in the U.S.A.
and watched for divergencies of opinion on technical or commercial aspects. No differences on technical
points have been traced by the Americans but items of expenditure are criticised. The British
article shows a figure of £3000 dollars per mile road length [which might be a currency conversion mistake]
for operation and maintenance cost, but this is considered extremely high. The British costs are
based on a higher rate of electricity supply and seem to provide for a higher illumination on the
road.
- (To be concluded in the next issue)
- Lighting: Funding, Lighting: Levels, Lighting: Safety, Lighting: Specifications, Statistics: Accident Data
- B.T.H. Lighting Exhibits at the B.I.F. p15
- Mazdalux Street Lighting Lanterns
- The Mazdalux fluorescent street lighting lantern exhibited has been developed from the
prototype used in an experimental installation in Rugby. It was followed by similar installations
in London and in other cities and towns. The lantern provides illumination which preserves the
natural colours of the surroundings and is substantially free from glare. The comparatively large
light source gives very full coverage of the road and a broad even light distribution which embraces kerbs,
pathways and buildings. The Mazdalux fluorescent street lighting lantern is designed
for use with three Mazda 80-watt 5-ft. fluorescent lamps. It is neat and compact and
all the auxiliary lamp gear is housed within the lantern.
- A great deal of time and research has been directed towards the development of entirely new
lanterns to accommodate the Mazda electric discharge and tungsten filament lamps which
have been used for street lighting for years.
- Examples from the new "Stylised" range of Mazdalux side-entry lanterns were exhibited.
This range consists of 16 lanterns, each with the same design and appearance except for variations
in size, lampholder, reflector and glasswar. There are many advantages in this standardisation.
Lamps and glassware can be interchanged with only minor modification, and the same system of simple
maintenance can be applied to all the lanterns. For the first time, lanterns with a uniform
appearance can be installed throughout an entire city or town, the varied requirements of
such locations, as busy shopping centres, side streets and car parks all being catered for.
The shape and appearance of the lantern has been carefully designed to blend well with all types
of surroundings and to match both steel and concrete standards.
- The new Mazdalux horizontally enclosed lantern incorporates the results of many
years of research. The lantern is designed for use with either the 250-watt or 400-watt
Mazda mercury vapour lamp and well-known BTH principle of controlled cut-off
to give constant visual accommodation with a minimum of glare. Has a very pleasing daylight
appearance.
- Metrovick Range
- Particular interest was shown in the "Ripplay" centralised control system by which an electricity
supply authority can control off-peak loads. This involves an audio-frequency generating set at the control
centre and special relays or switches at each of the remote points where a switching operation is
performed. The generator unit injects into the power supply system a series of pre-arranged impulses
of a particular audio-frequency to which only the appropriately tuned relays or switches will
respond. Thus the load circuit can be opened or closed by the operator at the remote control point.
In its improved form, the "Ripplay" system allocates a single audio-frequency to each network,
and discrimination by sensitive relays of the vibrating reed pattern is provided by a method of low
frequency pulsing that givs twelve switching channels. An advantage of the single audio-frequency
is that it enables the injection plant to be simplified and thus reduces capital expenditure; further
it makes the system immune from interference caused by spill-over signals from adjacent and
interconnected networks.
- The Trafford and Welwyn were on show. The Trafford is an enclosed
weatherproof Group A lantern and is designed to take horizontal burning mercury discharge lamps of
250W or less. It can have either top or side entry. The Welwyn is for Group B. The body
and reflector comprise a one-piece casting which is fitted with a 6" single-piece refractor;
the lantern is suitable for 100, 150 or 200W metal filament lamps or 80 to 125W mercury discharge
lamps. The canopies of both these lanterns are made of a special alloy designed to reduce corrosion;
this alloy has been demobilised from war service, when it was one of several developed for the
manufacture of deck fittings and the like for warships.
- Lighting: Control, Lighting: Luminaires
- Westminster Adopts New "Keep Left" Guardposts p16
- Details of order of 600 gas and 600 electrically illuminated "Keep Left" guardposts by
Gowshall for the City Of Westminster.
- Other
- Letter from the Ripple Control Technical Committee p16
- After the reading of the paper "Remote Control by Superimposed Currents" by J. L. Carr
before the Institution of Electrical Engineers, comments were made on certain aspects of
ripple control notably concerning the possibility of interference due to spillover of
ripple signals from one undertaking to others. In the course of these his remarks,
Mr. H. Nimmo read a draft regulation which had been prepared for inclusion in the
Electricity Commissioners Safety Regulations and which stipulated certain standards by which
spillover and interference were to be judged.
- It is now appreciated that some degree of spillover of ripple signals between interconnected
A.C. networks cannot be avoided entirely. At the same time, methods other than using voltage
discrimination are available in practice which would ensure that such spillover signals would not
cause actual maloperations of relays on other networks.
- The manufacturers actively interested in this situation are Automatic Telephone and Electric Co. Ltd.,
General Electric Co. Ltd., Measurement Ltd. and Metropolitan-Vickers Electrical Co. Ltd.. As
a result of technical discussions between their representatives an alternative draft has been
evolved: "An undertaker shall not install or operate a new ripple control installation unless the
method of signal injection and layout of the undertaker's only network and that of adjacent networks
will not prevent the correct functioning of any existing ripple control installations."
- In order to ensure that details of the policy can be satisfactorily agreed should, for example,
difficult or unusual conditions occur on any jobs, the four manufacturers named above have agreed
to maintain technical liaison on matters pertaining to ripple control generally, and from January 1st, 1947,
they have formed a co-ordinating technical body, to be known as the "Ripple Control Technical Committee" for this
purpose. The proposals have been discussed with Mr. H. Nimmo who has, on behalf of the
Electricity Commissioners, indicated his approval of them. Mr. Nimmo has stated that
there is no present intention of making the original draft statutory before the electricity supply
industry is nationalised and as an interim measure the steps being taken by the Committee would
assist in ensuring that the non-interference policy would be effectively applied for all new ripple
control installations.
- Lighting: Control
- Southport Conference p17
- Details about the forthcoming 1947 Conference.
- APLE: Conference
- Public Lighting In Parishes p18
- Attention is increasingly and rightly being given to the important of providing public
lighting in streets, roads and public places in parishes. It is felt that those Parish Councils
which are already providing street lighting or which contemplate doing so will welcome a statement
of their powers and duties under the Lighting and Watching Act, 1833, and a summary
of the recent circular issued by the Ministry of Transport (Circular No. 599) relating to street
lighting generally. A very comprehensive and instructive handbook has been issued by
The National Council of Social Service entitled "Public Lighting in Rural Parishes" which provides
the Officials of Parish Councils with invaluable information.
- Lighting: Authority Organisation
- Lighting Service Bureau Engineer in Scotland p18
- Mr. C. J. King, B.Sc.(Eng)., A.M.I.E.E. has been appointed Lighting Service Bureau
Area Engineer in Scotland.
- Lighting: Personnel
- Engineering and Marine Exhibition p18
- Details of the first post-war Engineering and Marine Exhibition to be held in London.
- Other
- A.P.L.E. - I.E.S. p18
- Manchester Centre of the I.E.S. is arranging a joint session with members of the A.P.L.E.
on the 8th January 1948. It is hoped Mr. E. J. Stewart, M.A., B.Sc. will give a lecture
on "The Lighting of Housing Estates."
- Lighting: Theory
- The National Illumination Committee of Great Britain p19
- International connections have been re-established. A comprehensive report has been prepared by the Mine Lighting sub-committee.
Further sub-committees have reconstituted. Some sub-committes were not recommenced as the British Standards Institution already
has sub-committees of the Illumination Industry Committee. During the year, the following British Standards were issued: B.S. 1249 (Cast
iron street-lighting columns) and B.S. 1308 (Reinforced street lighting columns).
- Lighting: Specifications
- A.P.L.E. Session at the First Post-War Public Works, Roads and Transport Congress p19
- This will be held at Olympia, London from Monday, July 21st to Saturday July 26th. A session will be held
under the aupices of the A.P.L.E. on Tuesday 22nd July when Mr. N. Boydell, M.I.E.E. will give the paper
"The Development and Trend of Street Lighting by Electricity."
- APLE: Conference
- Siemens Exhibit at Public Works Exhibition p19
- The main feature of the Siemens display included a range of street lighting lanterns for Group "A" and
"B" roads. The three lanterns shown for Group "A" were the: Weston-Sieray, Dilux and
Halton-Sieray. For Group "B" the Newton-Sieray and Marton-Sieray were exhibited.
- Lighting: Luminaires
- Keith's Raising And Lowering Gear p20
- Description of Keith's Raising And Lowering Gear.
- Lighting: Installations
- Lamp Column at Hereford p23
- The concrete column displayed in the previous issue was made by
Broad and Co., Ltd.
- Lighting: Columns, Lighting: Installations
- Ministry of Transport Circular p23
- The MOT has now become the central authority responsible for street lighting and
has taken over from the Home Secretary the allocation of iron, steel and timber needed for
street lighting equipment. The Minister asks that special consideration should be given in
future to securing reasonable uniformity in lighting standards and draws attention to
the fact that the diversity of lighting standards adopted by lighting authorities on
adjoining lengths of road has, in the past, been a source of danger and inconvenience
to road users. The Minister also expresses the hope that as soon as practicable lighting authorities
will do their best to adopt the appropriate recommendations of the Report of the Departmental
Committe on Stret Lighting 1937. The Minister will issue any necessary authorisation
under the Defence Regulation 56A for street lighting schemes, except in so far
as streets on new housing sites or streets other than public highways are concerned, which
become within the province of the Minister of Health and the Secretary of State for Scotland.
- Lighting: Authority Organisation, Lighting: Specifications
- Personal p23
- Mr. William J. Gilchrist Davey has recently relinquished his position as
Lighting Research Engineer and Technical Adviser to Elm Works Ltd. in order to undertake
private consultative work.
- Mr. C. W. Sully, director of E.L.M.A. from 1922 until early in the war,
celebrated his golden wedding in July.
- Lighting: Personnel
- Superimposed High Frequency Ripples for Central Control of Electric Street Lighting by H. Horwood, A.M.I.E.E. p24
- Introduction
- It is generally agreed that the ideal way of controlling lighting from a central point
without the expense of separate cables is by means of superimposed high frequency currants.
These currents are small in magnitude compared with the main current and are of a frequency
many times higher than the main frequency. This has no effect on apparatus normally connected
to the supply but caused relays tuned to certain frequencies to respond and open or close a switch
when a specific ripple signal is received.
- Historical
- Attempts were first made to employ a ripple emmision of this source about half a century ago.
The early attempts were small scale experiments. Their line of attack was to aim at a much more
powerful signal than was commonly used, on the principle tht with plenty of power in hand
there would be a greater margin of safety to allow for relay friction interference due to
harmonics and signal attenuation. It also enabled them to employ a more robust and durable
form of relay. But a powerful signal over the whole network could only be achieved by the
installation of a very high-powered alternator, often quite out of proportion to the size of the
undertaking. This difficulty was overcome by series emission in place of parallel emission which
enabled them to inject the full riple strength into one small section of the network at a time.
Successive injections into the remaining sections in turn thus provided a powerful signal
over the whole network involving only a reasonable size of alternator. In this way
Actadis (action at a distance) Ripple Control system was evolved and was first put into
practical use some 20 years ago and is today still in the forefront. Meanwhile the exponents
of the parallel method of injection sought to solve the problem by refinements in relay design,
still endeavourign to retain the low powered signal.
- Modern System
- The modern method is to inject the Ripple currents on the H.T. side at the generating
system busbars. This is found to be more reliable than L.T. emission.
- There are still broadly the two methods in use:
- (1) Actadis Series Emission System: Uses a powerful signal and more robust relay.
- (2) Several forms of Parallel Emission: There are three now on the market. They provide
comparatively low powered signals with correspondingly more delictate and sensitive reception
relays.
- During the past 20 years over 50 installations of Actadis have been put into operation
with remarkable success; no serious failure has been encountered. The exponents of the
parallel emission systems have during the past few years installed a number of sets chiefly
for A.R.P. purposes with varying success. These installations have not yet in the main
had a chance to show their performance over a large scale town street lighting.
- Series Versus Parallel Emission
- It is asked why the series system - which so obviously gives the most reliable results - is
not adopted to the exclusion of the parallel system. There are several reasons:
- 1. High powered signal gives high reliability.
- 2. Maintenance costs reduced to a minimum.
- 3. Extensions to network improve efficiency of signals.
- 4. Freedom from inadvertent operation by harmonics and surges.
- 5. Emission may be sectionalised giving greater flexibility of control.
- 6. Sectional emission permits better ripple voltage control.
- 7. Foolproof operation due to absence of complicated coded relays.
- Disadvantages:
- 1. Networks with very heavy groups of interlinked feeders present difficulties.
- 2. Networks with more than one source of supply present difficulties.
- Operational Results
- Over the last 20 years, operational experience obtained in over 50 networks gives an average reliabiltiy
of 99.998%. The average failure for parallel systems is 1.8% when compared to 0.002% for the
Actadis series system. A fault incidence of 1.8% on a 2000 street lamp network means that 500 lamps
would either not light up or would remain alight during the day time.
- Lighting: Control
- Fluorescent Lighting in Chatham Town Hall p26
- Details of the decorative fluorescent fittings installed in Chatham Town Hall.
- Lighting: Other
- Personnel p26
- Mr. B. C. Ossitt of the Yorkshire Electric Power Co., has been appointed
Street Lighting Superintendent to the Borough of Nuneaton.
- Lighting: Personnel
- Adverts:
Poles Ltd,
The Association Of Metal Sprayers,
Stanton Ironworks Co., Ltd,
Siemens Electric Lamps And Supplies Ltd.,
Automatic Telephone And Electrical Co., Ltd.,
Engineering And Lighting Equipment Co. Ltd.,
British Gas Council,
Stewarts And Lloyds Co., Ltd.,
Holophane Ltd.,
British Electrical Development Association, Inc,
The British Thomson-Houston Co. Ltd.,
Concrete Utilities Co., Ltd.,
Metropolitan Gas Meters Ltd.,
Walter Slingsby and Co., Ltd.,
Willey And Co. Ltd.,
British, Foreign And Colonial Automatic Light Controlling Co., Ltd.,
Falk, Stadelmann Co., Ltd.,
The Horstmann Gear Co., Ltd.,
Broad And Co. Ltd.,
Metropolitan Vickers Electrical Co. Ltd,
William Sugg And Co., Ltd.,
Hobbs, Offen And Co., Ltd.,
James Keith And Blackman Co., Ltd.
Sangamo Weston Ltd. and
The General Electric Co., Ltd.
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