Measurement of capacitance and dissipation factor
Please refer to Measurement of capacitance and dissipation factor, page 55.
Thermovision (infrared camera) check for local overheating on connectors
At the maximum rated current, the bushing outer terminal normally operates at a temperature of about
+35 °C to +45 °C above the ambient temperature. Significantly higher temperatures can be a sign of bad
connections, especially at lower current loading.
Checking of oil leakage
Make a visual inspection for oil leakage during regular station supervision.
After repairs
Hitachi ABB Power Grids recommends that the capacitance is measured after repairs have been done, after
maintenance of connected equipment, or after work near the bushing is completed.
It is important to compare the capacitance before energization with the capacitance that was measured at
commisioning. A change in capacitance gives indication of a fault. Refer to Measurement of capacitance and
dissipation factor, page 55.
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Installation and commissioning guide
1ZSC000563-AAF EN, REV. 4, 2021-06-23