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7. Cobb River Scheme. —Construction and erection of penstocks was completed, and after satisfactory test the generating plant was put on commercial load early in the year. Supply to the Golden Bay and Waimea Electric-power Boards and the Golden Bay Cement Co. was given on 6th June, 1944. The 66 kV. transmission-line to Blenheim was completed in December, and supply was given to the Marlborough Electric-power Board on Ist January, 1945. The system maximum demand was 5,400 kW., and occurred at 1930 hours on 28th January. The system output was 19,540,739 units, and transmission and distribution losses were 5-3 per cent. The generating plant required considerable attention for the first six months of service, but all other power-station and substation equipment and all transmission-lines operated satisfactorily and only the normal amount of maintenance work was necessary. A survey party has commenced work on a reconnaissance survey to explore the best route for connecting the Cobb Scheme with the South Island network via the West Coast. Registration of Electrical Wiremen Examinations were held for electrical wiremen, electrical servicemen, radio servicemen, radio transmitters, cinematograph operators, and luminous-discharge-tube servicemen. Special examinations were again held in the Pacific and Middle East areas for members of the Armed Forces. Credit tables dealing with electrical experience obtained by electrical apprentices and other personnel whilst in the Armed Forces were prepared and distributed, and have proved valuable in enabling a uniform assessment of credit to be granted, irrespective of in which Service the experience has been obtained. For the September, 1944, examinations, 625 candidates sat, which constituted a record, the previous highest number being 600 candidates in September, 1929. During the year the Registration Board assumed full control of the actual conduct of the examinations, this work having previously been carried out by the Education Department. Consideration of the experience of prospective rehabilitation trainees has figured largely in the business of the Board during the year, and will continue to do so as demobilization proceeds. Design Office Structural Section Further preliminary planning was carried out for Tekapo and Maraetai Power-stations on receipt of tender data and drawings from the contractors for the machinery. Other design work for powerstations included control-room alterations at Waikaremoana Main Station, structural alterations at Lake Coleridge to suit new outdoor station, and two-stall and seven-stall concrete garages at Cobb River. The latter, which are for rental to the operating staff, are very necessary in view of the isolation and the unfavourable climatic conditions. Switch-room buildings were designed for Greytown, Marton, Pahautanui, Upper Hutt, and Waiuku Substations, and a new workshop building for Mangamaire Substation. Plans were prepared for a workshop at Nelson Depot, and for a furnace-room at Hamilton administrative building. Drawings and specifications were prepared for a new hostel at Highbank and for additional staff quarters at Bombay and Dobson. Other staff accommodations was designed by the Housing Department. Electrical Section The requirements of lightning-arresters for all districts were investigated and essential data for specifications was prepared. The cable requirements for all districts were scheduled for the annual bulk order for cable. The metering procedure at all power-stations was investigated, and a uniform metering scheme developed for all installations. Numerous short-circuit calculations were carried out in connection with inductive interference calculations and investigations of circuit-breaker rupturing duties. Inspection of locally manufactured transformers was made at various times. Preliminary designs were prepared for 220 kV. switching structures sufficient to determine the quantity and type of equipment required for Maraetai, Whakamaru, Otahuhu, and Bunnythorpe. Drawings of the various items of equipment were prepared for specification purposes. A preliminary structure layout was prepared for Otahuhu Substation to determine the amount of land required. Preliminary layouts were also prepared to confirm the suitability of a site at Haywards for a future 220 kV. substation in the Wellington area. The equipment required for 220 kV. transmission made it necessary to investigate transport problems. Arrangements were made with the Railways Department for the construction of a special well-type wagon capable of carrying a load 20 ft. long by 10 ft. 6 in. wide by 12 ft. high and weighing 40 tons. Essential specification data was prepared for the ordering of a well-type road trailer of similar capacity. In the case of equipment for the new substation at Bunnythorpe it will be necessary to use road transport from Wellington to Paekakariki and rail transport between there and Bunnythorpe, because the loads are too large for some of the railway tunnels and too heavy for the road bridges at the Waikanae, Otaki, and Ohau Rivers. With the large amount of design and construction work in view in the near future it was felt that some form of standardization was necessary, and a considerable amount of time and effort was expanded in compiling a folder of over sixty standard drawings. These drawings refer mainly to the details of construction wiring and layout of equipment inside the substation building and have already had considerable application.

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