ELECTRICAL ENERGY

Manawatu Standard, Volume XLV, Issue 120, 23 April 1925, Page 4

ELECTRICAL ENERGY

BUNNYTHORPE SUB-STATION. A MODEL INSTALLATION. To the layman, perhaps, the most Striking feature of the work of the Mana-watu-Uroua Power Board is its sub-station at Bunnythorpo. whence the board distributes hydro-electric power to all quartern of the Manawatu district. The sub station, which has now been successfully in commission for a considerable -time, will be officially opened on Monday afternoon, when a suitable tablet will be affixed to the building. Through the courtesy of Mr \\. A. Waters, chief engineer to the board, a “Standard” reporter was yesterday enabled to inspect" the building and apparatus which was explained in detail by the expert mentioned. The building itself, and to a certain degreo the apparatus, have been described before. Tho structure of brick presents a pleasing architectural appearance, while the mnze of wires leading to the polos outside leaves the visitor in no doubt as to its character. The substation was first placed in commission in September, 1924, and, together with the cost of the operator’s cottage near-by, involved an outlay of over £BOOO. The contract price of the switciigeur was £3750. and of the lightning arrestors £SOO, apart from the cost of erection. BEST MONEY CAN BUY.

The impression formed on tho layman w ho for the first time sees the interior of tlie building is first admiration for the orderly array of masses of electrical gear extending high overhead, tho whole guarded by a steel netting cage, for within arc hundreds of wires which if touched would result in instant electrocution. One cannot fail to be impressed with the silent efficiency of the scheme for, though there is not a sound within the station, 300 horsepower—sometimes more and sometimes [ess—is being distributed to industries and homes' throughout the district and every bit of the output is registered with infallible accuracy. The future holds no terrors for tho board, for the plant has been designed to handle 7000 lc.v.a. if necessary, or as much power as ever the Government schemes could be called upon to supply to the Manawatu. “All of the apparatus is the best that money can buy,” said Mr ’Waters, adding that any part if necessary 4 could be repaired without interruption to the rest of the scheme. “We don’t expect to have to do much repair work though.” he commented confidently. In the sub-station are telephones with direct communication with Palmerston North, Feilding, and Mongahao, while Dannevirke and Marton can be communicated with without delgy. The Power Board officers, therefore, are fully prepared in tho event of trouble with tne general scheme, and the board’s efficiency in remedying any breakdowns at any hour has already become proverbial in this district. That at Bunnvthorpe is one of the largest power board sub-stations in the Dominion, while alongside it stands the Public Works Department’s sub-station which in years to come will be the greatest power concentration point in New Zealand, for it will connect up with the whole of the North Island system of hydroschemes. Tho building is liberally lighted and about the walls ure electric lamps in ornamental fixtures and served by an independent battery should there be a com plete breakdown by night. WHEN THE MILKING STARTS.

In a long row stand the recording devices which operate all through the 24 hours and which with infallible precision record on a chart tho amount of power received from Mangaliao and the amount of current sent to every quarter of the district and which also records just how the load was made up at any time. “See here,” said the chief engineer, drawing the reporter’s attention to the instruments and pulling out a roll of paper from one of them, “lliat red ink line shows how the demand was made up on this section ior the past 24 hours. That little jog in tho line denotes the starting up of tho first milking plant at 3.16 a.m. Yes, it is an ear(y hour to the townsman all right. Tho next motor was switched on soon after and you observe that the record has many ‘wavers’ denoting the starting up of other plants in more rapid about 5.30 a.m. The line falls again during tho period when milk is being taken to the factory and recovers steeply on this section When the freezer at the factory is started up and the general machinery is put into motion to deal with supplies. “Take another chart. The red line shows a continuous up aud-down blur for some inches and then remains straight for about half an inch and then goes on aguin marking emphatically. That is the record of the working of a fiaxmill at Karere with the ‘smoko’ time faithfully recorded. That the pulse of industry throughout the Manawatu should bo so sensitively felt ie jgk wonderful medhanical achievement, burc that is only a. minor feature of the substation. BAFFLING THE LIGHTNING. Naturally, in an electrical undertaking of magnitude, the danger from lightning has to be guarded against effectively. That is why nearly Half of the interior of tl»e sub-station is occupied by the lightning arrestors. “This is one of the worst districts for lightning I have known,” said Mr Waters. "On occasions we have received 70 discharges an hour through the apparatus, which removes all risk of danger. We can tell which way an electrical storm is travelling by the order in which the various sections, are affected. Through this apparatus we do not need to wait for an audible storm to receive discharges. We get them on a warm afternoon or when ‘statio,’ the bugbear of the wireless en thusiast, is unduly prevalent.” SAFETY PRECAUTIONS.

Mr Waters explained the procedure in guarding against injury to men who went out to vvork on lines controlled from the sub-station. He showed the rows of master switches whioh were locked out and made doubly safe by withdrawing an extra control high overhead, when a gang was on the line. When u man went out he first reported to the sub-station and was given a card with u code number after signing his nume on a card which was time-punched by an automatic device and placed in a receptacle which displayed it over the locked-out switch. No one could replace the switch until the man had advised that the lino was oleur and Jtad cited his oode number. If he forgot ft, or lost his card, ho had to report in person before current was restored. OTHER DETAILS. There are elaborate arrangement# for giving warning automatically when anything goes wrong and a complete record of where and when a fault occurs is kept by the recording machines. Tho 12 switches at present serving different quarters of the district aro all in separate fireproof steel boxes, for a switch might, bum out and ignite the bath of oil attached to it. To describe in detail the apparatus would not afford much know ledge to the layman and it is only by personal inspection that the whole splendid unit can be fully realised.

THE GOVERNMENT SUB-STATION. Close by the board’s premises is a mas« of 'battleship grey” steel-work in the open air, extending over a space some -182 feet long, 50 feet wide and some 60 feet nigh. That is the Public Works Depart meat's switch-gear from which radiate the power transmission fines from Mangahao (duplicated) and outwards already as fair as Mastorton, Waipawa in the Hawke’s Bay, and nearly to Wanganui. It j s a vast control system destined to become the electrical hub of the North Island I here is a noise like the sound of hun‘ dreds of crickets, caused by the “spit, ting of the current as it posses through the devices overhead inbp the transform, era, which themselves maintain a subdued hum. At night little stabs of blue flame are the only visible evidences of the vas* power which is here being controlled ami sold as is any other commodity essential to the industry of a country.