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These pictures are from Wairau Valley Road substation in Glenfield, North Shore, Auckland.

This substation is fed from 3 x 110 kV lines ( double cct 110 and single cct 110 lines ).

Maintenance was done on the double 110 kV line to replace the aerial earth wire.
The cct 1 and cct 2 lines were shut down for the whole weekend during the earthing upgrade.
Saturday afternoon the temperature shot up in the switchyard which is in a valley to 35°C(95F),no wind,
This happened on Saturday 10 March 2007 around 1400 hrs.
The 33 kV load went up from 1000 to 1200 Amps.
110 kV current was around 340 Amperes.
Temperature meters increase to critical tripping point 85°C
OFAF rating is for 2 hours only with oil pump running and fans on.
Simple solution I suggested, knocked down the temperature around 5°C within the hour by applying 2 garden hose sprays atop the radiators to assist with extra cooling of the oil. ( We did this also in the Auckland CBD meltdown in 2000 ).

We managed to avoid a trip and large area black out on the north shore.
For the rest of the Saturday and Sunday, during daylight hours we left the hoses running.
At night they were turned off and ammeter readings dropped to around 800 Amperes.

I will add more comments when the photo's are posted.

Raymond ( Rodalco )