2.2 EFFECT OF ADSORPTION OF BTA ON SOLID
INSULATOR
The adsorption of BTA on solid insulators such as
pressboard and coil insulating paper occurs in transformers.
If the concentration of BTA in oil decreases by this
adsorption, there is a possibility that the ECT-suppression
effect of BTA on insulating oil decreases. To examine the
effectiveness of BTA when used together with pressboard,
the relationship between the trends of ECT and BTA
concentrations is investigated by the thermal aging tests.