D—4

Machine-running Times

Dobson. —The Diesel station ran as required until September, when the discovery of cracks in three of the four main engine crankshafts reduced the engine availability to one. Owing to the antiquity of the engines, replacing major parts presented a difficult problem, but arrangements have now been made for the supply of these parts.

Machine-running Times

2. Substations (a) 110 W. Operations at 110 kV. substations were normal. (b) 66 kV. Invercargill. —Extensive trouble was experienced with the two voltage-regulators, there being numerous breakdowns, which are the subject of special reports. A similar regulator was borrowed from Milton Substation and the two damaged ones repaired. Ohai. —An operational error caused damage to the regulator, which was repaired. (c) General Three equipment failures were associated with the heat wave in February, but there is no actual evidence that the heat wave was a contributing factor. 3. Transmission and Distribution (a) 110 hV. Lines Glenavy-Oamaru. —Two large horse-shoe boulder groynes to protect the towers on the north and south banks of the Waitaki River were completed.

21

Time on Load. Time Idle. Time Under Repair. Percentage Availability for Service. Generator No. Hours. Percentage. Hours. Percentage. Not in Demand (Hours). In Demand (Hours). 1 2 3 6,377 6,647 5,955 72-8 75-8 68-0 2,327 2,064 2,699 26-6 23.- 6 30-8 56 49 69 37 99-4 99-4 98-8

Time on Load. Time Idle. Time Under Repair. Percentage Availability for Service. Generator No. Hours. Percentage. Hours. Percentage. Not in Demand (Hours). In Demand (Hours). 1 2 3 4 82 221 103 0-9 2-5 1-2 1,808 8,'539 3,579 20-6 97-5 40-8 6,870 8,760 5^078 21-5 0-0 100-0 42-0