摘要:

In this paper the author proposes that British manufacturers should collectively standardize overall and fixing dimensions of commercial electric motors covering a range of approximately 1 to 50 h.p. Design within the range quoted having approached finality, it is suggested that the time has arrived when standardization cannot be further delayed without prejudice to our postwar effort to secure a wider market.The advantages quoted for standardization comprise a saving in drawing and erection costs, more prompt deliveries, avoidance of delays, fewer spares, saving of stores space, interchangeability and ease of replacement in the event of breakdown.Suggestions are made as to the dimensions it is desirable to standardize, and attention is called to the importance of fixing a standard position for the terminal block.Objections which have been advanced against the proposal are considered and answered. These comprise the cost of re-drawing and re-tooling, disorganization of production, restriction of development, loss of sales points and the fact that there will be no immediate gain.Reference is made to work already done, and it is suggested that delay may have resulted from there being two schools of thought, one connecting standard dimensions with output and another concerned with laying down standards for frame sizes.The degree of standardization already achieved in the U.S.A. is considered, and the paper concludes with remarks upon the possibility of standardizing control gear.

DOI:10.1049/ji-2.1943.0058

出版商:IEE    

年代:1943

数据来源: IET

摘要:

The paper reviews the considerations which apply more particularly to hospitals than to other public buildings. For permanent work, paper-lead cable is recommended for the circuits to the fuse-boards and wiring in conduit for the subcircuits. Under-floor ducts are not recommended for hospital wiring. Suggestions are made regarding the selection of accessories and fittings. For general ward lighting a comparatively low value of horizontal illumination is recommended, with local lighting at the beds. Capacitance dimming is described. The use in the future of fluorescent lamps is discussed. The shadowless lamp for operating-table lighting is described. Precautions to be taken against explosions in operating theatres are referred to. Requirements for screening in connection with high-frequency (diathermy) apparatus necessitated by war conditions are reviewed, and the opinion is expressed that regulations for this will be continued after the war. The precautions necessary in the construction and use of apparatus for electric therapy are discussed. Developments in X-ray apparatus are mentioned, and questions of voltage-drop and shielding briefly discussed. On ultra-violet treatment, the opinion is expressed that the mercury lamp, possibly supplemented by ordinary tungsten-filament lamps, should eventually entirely displace the more expensive arc-lamp treatment, and that there is no need to aim at an artificial reproduction of sunlight. Other subjects which are dealt with briefly are infrared rays, cardiograph wiring, heating, ventilation of operating theatres, water supply pumps, cooking, refrigeration, lifts and signalling circuits.

DOI:10.1049/ji-2.1943.0060

出版商:IEE    

年代:1943

数据来源: IET

摘要:

The paper examines the history of integrating meters, the large number of early types, and the fact that, the electrical industry having grown so rapidly, any attempt at standardization was not practicable until recent years.The introduction of British Standard Specifications for all classes of electrical equipment helped in standardizing the performance of meters; and the second stage, that of the standardizing of components, is discussed in detail.The author arrives at the conclusion that standardization would be of ultimate benefit to the community, but that it can only be accomplished in stages.

DOI:10.1049/ji-2.1943.0062

出版商:IEE    

年代:1943

数据来源: IET

摘要:

The paper has been prepared as an introduction to this important field of new development.Notable improvements in circuit-breaker design are discussed in particular, with reference firstly to the reduction in oil quantities and subsequently to its elimination. The principal characteristics of air-blast circuit-breakers are reviewed and comparisons between oil and oil-less circuit-breakers are madeThe cross-blast breaker, a recent American development, is referred to, but the paper deals principally with breakers of the axial-blast type developed earlier by Brown Boveri in Switzerland and the A.E.G. in Germany, both of these companies having done much pioneer development for several years with this class of apparatus and both having installations in service in this country to-day.Switching conditions affecting the rate of rise and the magnitude of recovery voltage are discussed, and cathode-ray oscillograms are presented which verify how these factors are affected by the use of resistors connected in parallel with the arc.A description of 11-kV and 66-kV air-blast circuit-breaker designs is given, and the application of these designs to service equipments is reviewed.

DOI:10.1049/ji-2.1943.0064

出版商:IEE    

年代:1943

数据来源: IET

摘要:

The purpose of this paper is twofold:—(a) To draw attention to means of improving the method of installing the electricity services into residential premises. It urges that present-day methods should be improved by the adoption of standard service apparatus and its mode of installation. The service arrangements provided should be made suitable and adequate to deal with the requirements of the consumer, and should anticipate his possible future loading.(b) To show that while it is certain that we shall ultimately develop still better and more convenient systems of wiring if house materials move away from the traditional bricks and mortar it is clear that even with existing materials the small house with all reasonable electric facilities is easily within our reach at a small expenditure. One might almost say that it is within reach for the same expenditure if we spend more intelligently. A very large measure of agreement could be obtained for building houses with the equipment described. Let us accept this as a standard and get on with the job, and reluse to cloud the issue and arouse unnecessary opposition by talking about all-electric houses.

DOI:10.1049/ji-2.1943.0067

出版商:IEE    

年代:1943

数据来源: IET

摘要:

This paper deals with the methods and materials that may be used after immediate post-war needs have been met. It traces the development of wiring methods up to the present time and indicates the direction in which improvements may be considered.The importance of services is particularly emphasized, and it is suggested that the house itself should be designed around the requirements of, and with specially detailed reference to, the services it contains.Alterations to existing regulations to incorporate convenience and adequacy as well as safety are discussed, together with the effect of such alterations on the methods in use at the present time.Proposals are indicated whereby newly developed materials used for the structure of the house may in themselves incorporate the wiring needs, and the paper concludes with notes upon accessories and equipment.

DOI:10.1049/ji-2.1943.0068

出版商:IEE    

年代:1943

数据来源: IET