It is very important to take samples of paper from the windings of transformers at the end of their life, to improve the models of furans interpretation and to have indications on the thermal aging of similar equipment.
A brief list of controls on failed/dead transformers is:
- Visual inspection of windings degradation
- Paper DP, sampling from higher side of windings
- Detection of moisture and polar compounds in the paper
- Metal content in the paper
- Analysis on sludge and deposits
- XRF or EDX spectroscopy on paper and pressboards
Paper sampling
