DBDS corrosive sulfur - C1
is a problem relating to the corrosive properties in oil and other insulating liquids which affect the metal surfaces of some copper or silver components inside transformers and other electrical equipment, such as conductors and contacts. The problem is caused by the presence of an additive in the oil called DBDS (dibenzyl disulfide). “DBDS corrosive sulfur – C1” occurs under normal transformer operating conditions
Corrosive sulfur
Free sulfur and corrosive sulfur compounds detected by subjecting metals such as copper to contact with an insulating liquid under standardized conditions
[SOURCE: IEC 60050-212:2010, 212-18-20]
Dibenzyl disulfide (DBDS)
Aromatic disulfide containing two benzyl funcionalities with a molecular formula C14H14S2, nominal molecular mass of 246 and a melting point of 71-72° C
[from IEC 62697-1 of 2012, para. 3. 1. 7 – p. 10]
The concentration of DBDS as an undeclared additive was used widely between 1989 and 2007, in typical concentrations of 180-200 mg/kg.
