ELECTRIC WIRES

Press, Volume LXX, Issue 21198, 23 June 1934, Page 14

ELECTRIC WIRES

MELBOURNE SYSTEM EXPLAINED SPECIAL CONDITIONS IN SPECIAL AREAS When a picture of a garden suburb of Melbourne with all the electric cables and telephone wires placed underground was published in "The Press" on May 9, the electricity committee of the Christehurch City Council instructed Mr E. Hitchcock, general manager of the Municipal Electricity Department, to write to the ; electrical authorities in Melbourne and find out all about it. The reply emphasises Ihat it is only in a few isolated areas that the ordinary system of overhead construe- j tion of wires has been departed from, and that those areas are governed by special conditions. It says that the wires have not been placed underground, but along the rear of the properties. and that considerable assistance was given by the builders. Sixpoints for particular note are set out as follows: (1) Lempriere avenue, the street in the picture, is a cul-de-sac street, approximately 220 yards in length, and contains six 100-watt street lamps. Four of these lamps are erectecj on spun concrete posts, and the other two, which are at the end of the street, where there is an entrance to public gardens, are on masonry pillars. The lamps are staggered and are spaced at approximately 55 yards along the street. Poles iii a Lane (2) To service the houses on one side of the street poles have been erected in a lane or right-of-way. and to service houses on the other side the poles have been placed along an 18inch easement adjoining the line. Five of the street lamps are supplied from the mains at the rear of the houses by vulcanised india rubber wires in pipes attached to the dividing fences as far as the low concrete front fences of the residences and thence by underground twin lead-covered vulcanised india rubber wires in earthenware pipes to the lamp pillars. The other street lamp is supplied by a paper insulated lead-covered and armoured cable from the pole at the head of the street—a distance of only three yards. (3) Where underground street mains and services are decided upon we are of the opinion that an 0.1 square inch 4-core cable in three phase areas should be laid along the street, and that such a cable should, taking diversity into account, be sufficient for seveial years to come. The service cables would be made of sufficient capacity _to meet all reasonable increments oi load in individual premises. This particular problem, however, was discussion" tered the locaJit >" undeiA 1 13 houses in the street. All ot the houses have an electric hot water system and two have electric ranges. . There are 17 to 35 lamps intr, 19 ° aCh . r f idence - and also six abniTt i,- ? r l?°. lnts supplying, in total, about 1G I'adiators and various other portable appliances. Assistance From Builders (5) The builders who subdivided the estate supplied and erected the concrete pillars, globes, and earthenware , piping for the street lamps and bore the cost of the wiring ,from the suplily mains to the lamps- The muni-

cipal council pays the annual charge for the lamps, the annual charges for each lamp being that which is applicable to the ordinary standard bracket litlings erected by this undertaking. Also, the builders were required to pay the cost for supplying the premises with electricity over and above that which would be incurred if the ordinary street reticulation had been adopted. This principle k applied generally where parties reojire a variation from standard cone emotion, whether by underground cables or by additional poles along right-of-waVs or easements. (6) As indicated above, departure from the ordinary overhead reticulation in streets has been made only in a very few areas, and consequently we have no general figures of cost readily available. In the letterpress under the picture it was stated that the removal of poles and wires from the inner area of the city had been suggested frequently by members of the Christchurch Beautifying Society. The electricity committee noted that and has sent a copy of the reply to the society.