Contents
1. Introduction
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1.1 Required tools
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1.2 Required material
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1.3 Oil
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1.4 Oil conservator
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1.5 Filter unit for continuous oil filtration
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1.6 Weights
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1.7 Tightening torque
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2. Receiving
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2.1 Unpacking
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2.2 Inspection upon receiving
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2.3 Temporary storage before assembly
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3. Drying ____________________________________________________________
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4. Installation on the transformer
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4.1 Attaching the on-load tap-changer to the transformer
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4.1.1 Welding
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4.1.2 Bolting
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4.1.3 Assembly of accessories
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4.1.4 Retightening
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4.2 Connection of the regulating winding of the transformer
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4.3 Connection to the oil conservator
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5. Pressure relay
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5.1 General
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5.2 Installation
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5.3 Checking when commissioning the transformer
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6. Oil filling
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6.1 Filling methods and restrictions
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6.1.1 Retightening
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6.2 Filling at atmospheric pressure
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6.3 Filling under vacuum
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6.4 Correct oil level
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7. Electrical connection and testing
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7.1 General
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7.2 Connecting and testing
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7.3 Electrical tests on transformer
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7.4 After energizing
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7.5 Resistance measurement
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8. Transport
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8.1 Oil level during transport
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8.1.1 Transformer filled with oil
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8.1.2 Transformer drained
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