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Installation and commissioning guide
2750 515-1 EN, REV. 14, 2020-06-26
Waiting time before energization ................................................................................................................................................. 61
Recommended test before energization ..................................................................................................................................... 62
5.2.1
Overview ................................................................................................................................................................... 62
Tightness test between transformer and bushing flange........................................................................................... 62
Tightness test of bushing outer terminal.................................................................................................................... 62
Measurement of capacitance and dissipation factor ................................................................................................. 63
Measurement of through-resistance.......................................................................................................................... 66
Recommended maintenance ...................................................................................................................................................... 67
Checking the oil-level .................................................................................................................................................................. 69
Taking oil samples ....................................................................................................................................................................... 70
Removal of the bushing from the transformer, draw rod ............................................................................................................. 73
Removal of horizontally installed bushings ................................................................................................................................. 76
Re-packing of the bushing........................................................................................................................................................... 78
Summary ..................................................................................................................................................................................... 79
Spare parts.................................................................................................................................................................................. 79
Special tools ................................................................................................................................................................................ 81
Disposal and environmental information
Overview ..................................................................................................................................................................................... 83
Disposal and recycling ................................................................................................................................................................ 83
Summary ..................................................................................................................................................................................... 85
Measurement record ................................................................................................................................................................... 87