DAMAGE AT ARAPUNI

Taranaki Daily News, 25 February 1935, Page 4

DAMAGE AT ARAPUNI

FIRE IN ONE POWER UNIT the COST SEVERAL THOUSANDS. CABLE SENT SWEDEN COSTS DAY’S CHAPTER OF ACCIDENTS. By Telegraph—Press Association. Auckland, Last Night Serious dam a ®®» estimated at several thousands of pounds, was done at the Arapuni power station on February 15, it is now learned, when the windings of No- 1 generator caught fire and toe unit was thrown out of commission, A chapter of accidents happened at Arapuni on that date. An insulator fault in an outdoor station interrupted the service in Jhe whole district supplied by Arapuni for six minutes, A second insulator fault occurred in the outdoor station later and there was another dislocation of the service for a time. The major calamity occurred at 1.25 p.m., when an electrical fault, the cause of which will probably never be known, happened in foe generator windings of the No. 1 unit. The automatic ‘ cutout” apparatus came into play immediately and the load generated by foe plant was taken up by another unit, which previously had not been fa operation except for a “jump fa lighting and power services. The accident was not noticed by anyone outside the station. From the time the fault occurred to the time the rotation of foe unjt could be stopped by the application of the air pressure brakes six minutes elapsed. During that period the cambric and cotton tape insulation covering the copper windings surrounding the stator burst into flames and awe-inspiring sight was presented, t The station staff under the superintendent, Mr. A. C. Thompson, did excellent work with the fire-fighting equipment, and it was not long before the firg was suppressed. Extensive damage was done to the windings, and it was rt first thought that the major portion of the plant would have to be replaced. An order was sent fo foe manufacturers of the unit, the Asea Gompw Sweden, for new Parts, but the company cabled a reply suggesting that foe order should be delayed pending the receipt of a detailed description of foe requirements. The return cable embodying this description cost £5O to send, intricate and technical were the of the parts affected. A reply to this message is being awaited. - j In the meantime, the super-structure and rotor of the unit had been removed, leaving a cavity which, discloses the burnt windings of the stator and the effect of the severe heat which was generated between foe time the fault occurred and the rotation of the unit wa§ stopped. No damage was done; to foe buildings. Mr. $, Lamburd. managing director for New Zealand of foe Asea Company, has spent two days at Arapuni co-operating with the staff of the Public Work? Department ip assessing foe extent of fee damage. Mr. F- M. B - Kwl. ehief eleetrjcgl engineer of the department, Wglifagtop, and Mr. T. MacLeiuian, dirtrlet engineer,’ Hamilton, visited foe works yesterday. Of fop four mafa units installed at Arapufo. foree are operating and are able to cope with the needs of the district served by the station. It is expected that many months will elapse before foe No, 1 unit will again be fa Working order, It wa§ this unit that gave the engineers a great deal of trouble when it was first ’ installed. It was at first believed that it was slightly off balance, but after it had been dismantled the fault was found to be dye to a defective part. When this fault was corrected the machine operated successfully. The engineers are satisfied that the recent fire had nothing to do with foe defect whiph caused so much anxiety two years ago. The stoppage of foe No. 1 unit will cause delay in completing the excavations for two additional units that ar? to be installed.