DBPC can suppress the conversion of sulfide to sulfoxide by
blocking the generation of peroxide. However, both hydrogen
and DBPC radicals possess no charges. This is different from
the dissociation of BTA. Thus the addition of DBPC in
sulfoxide-added oil is not effective for suppressing the
increase in ECT.
These typical additives are found to have different effects
on the ECT. Thus it is important to ascertain the charging
conditions in insulating oil through the analysis of sulfur
compounds in oil.