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The General Electric Co. Ltd
Magnet House
London WC2

1914 logo

Mid 1930s logo

Exhibits included street lighting lanterns specially designed for Osram Tungsten filament gas-filled and Osram high-pressure Mercury Vapour lamps (MA) including an entirely new type of dual purpose lantern for accommodating either types of lamps. Another new lantern exhibited was one designed especially for use with the 150W MA/H. The well known Lewisham and Di-Fractor types were also on display. - Public Lighting #3, 1936

The firm are exhibiting the "well-known" Di-fractor lantern with 400W MA/V lamps at the Folkestone APLE conference in 1937 to the recommendations of the interim report of the Ministry of Transport Departmental Committee on Street Lighting. A cut-off system of lighting using a new type of GEC lantern is also exhibited, which burns the lamp horizontally without any additional gear, and leads to a very compact lantern with internal silvered mirrors. The Plafractor lantern is also being exhibited. - APLE Conference Programme 1937

The vast possibilities of a system for centralised control of street lighting and air raid signals, developed by the GEC, were demonstrated by a model at the I.M.E.A. Convention at Torquay. The system employs carrier currents of musicial frequencies superimposed upon the supply network conductors. Pilot wires are not required. A variable speed motor-alternator set at the substation provides the range of frequencies from which one can be selected to operate various tuned relays installed at the controlled points. (These frequencies range from 200 to 800 cycles per second and are chosen to avoid the harmonics and resonant frequencies of the power network.) Usually six to eight frequencies can be catered for without difficulty. In light of ARP schemes, and in addition to the advantage of controlling street lights, buzzers can be installed in all houses of air raid wardens and operated from the control point. It would be possible to apply the system to the control of water heaters throughout the supply area if any project should be entertained involving the provision of cheaper current subject to the power for this service being cut off during peak periods. The demonstration model consists of a primary substation feeding a secondary substation, both situated on roads illuminated by street standards. At the primary substation is fitted a small control panel, at which street lights can be switched on or off, either completely or in groups. The model also includes a buzzer as a warning signal in the house of an air raid warden. - Public Lighting #10, 1938

Two new lanterns take centre stage: the new Difractor (for burning mercury lamps vertically) and the new Horizal (for burning them horizontally). The Horizal uses a magnetic deflector to control the arc. Wax filled chokes are also being exhibited along with the GEC's centralised control of street lighting which works on the ripple system. - APLE Conference Programme 1938

A second model was produced in late 1937 or early 1938 to illustrate the recommendations of the MOT Final Report. It featured a realistic system of streets bounded by houses, cinemas and factories. The model measured 5' long by 2' wide, the lighting columns, road and spacing being to a scale of 1':380'. Running the whole length of the model was a main arterial road - this was lighted by columns providing a mounting height of 25'. The two sections of the arterial road, which was divided by a roundabout, was over 40' wide: this was lit by a staggered arrangement of units not more than 150' apart, with an auxiliary unit centrally suspended every third position, so that there was no dark central section of the road. After the roundabout the road was made into a dual carriageway, the central reservation being over 6' broad. Dual carriageways were treated as two separate roads, each having a staggered arrangement of lighting points with an average spacing of 150'. The fact that the central island was more than 6' broad necessitated the use of a column carrying two lanterns, each lantern being suspended over its own carriageway. Where the dual road bent away the lighting points became closer and positioned on the outside of the bend only. Branching from the roundabout was another road which shortly divided into two, the major portion becoming an S bend. Round this bend the spacing became very close in accordance with the rule that says the angular separation between lighting points should not exceed a certain number of degrees. Other examples included lanterns that indicated to side road traffic that a main road is ahead; cross-road lighting with lights arranged just beyond the crossing; and roundabout lighting. The model was installed at Magnet House, London, and could be viewed there. - Public Lighting #11, 1938

The Horizal and the newly introduced Uniway lanterns are being exhibited, and heavily promoted, by the firm for this conference. The Horizal was the first lantern to be designed for side entry whilst the Uniway was an entirely new concept for the lighting of dual carriageways. - APLE Conference Programme 1939

Major emphasis is given to the GEC Ripple Control with a separate advert and demonstration. It works by superimposing an audio frequency signal (or ripple) over the 50Hz power supply at a central point (usually a substation). The ripple signal is picked up at the receiving end (a street light) by a specially tuned relay which only responds to select frequency. They are also display a wide range of modern street lighting lanterns (including the Side Entry Di-Fractor, Double Dish and Totally Enclosed Cut-Off lanterns) but note that the "casual design treatment of earlier years is no longer adequate for modern requirements. The solution is to offer a range of lanterns, each with a specific application rather than a multiplicity of types differing only in their external appearance." - APLE Conference Programme 1945

The Illuminating Engineer 1928
APLE Exhibition Catalogue Blackpool 1932
APLE Conference Programme Folkestone 1937
APLE Conference Programme Bournemouth 1938
APLE Conference Programme Glasgow 1939
APLE Conference Programme Glasgow 1945

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