## 2 Quantitative Test Methods for Different Suphides in Transformer Oil
\begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Company** & \multirow{2}{*}{**Transformer Name**} & **Corrosive** & **Voltage** & \multirow{2}{*}{**Delivery Time**} & **Oil Brand** & **Oil** & **Manufacturer** & **Oil Group** \\ \cline{4-9}  & & & & & & & & \\ \hline \multirow{4}{*}{\begin{tabular}{c} Quan \\ Zhou \\ \end{tabular} } & \multirow{2}{*}{Tuzhai No.1} & \multirow{2}{*}{3b–4a} & \multirow{2}{*}{220 kV} & \multirow{2}{*}{2 December 2004} & \multirow{2}{*}{\begin{tabular}{c} Nynas \\ GBX \\ \end{tabular} } & \multirow{2}{*}{Nynas} & \multirow{2}{*}{Cycloalkyl} \\  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \hline \multirow{2}{*}{\begin{tabular}{c} Nan An \\ \end{tabular} } & \multirow{2}{*}{Humei No.3} & \multirow{2}{*}{2e} & \multirow{2}{*}{110 kV} & \multirow{2}{*}{14 December 2008} & \multirow{2}{*}{DB-25\#} & \multirow{2}{*}{Karamay} & \multirow{2}{*}{Cycloalkyl} \\  & & & & & & & \\ \hline \multirow{2}{*}{\begin{tabular}{c} [PERSON] \\ \end{tabular} } & \multirow{2}{*}{Hualin No.2} & \multirow{2}{*}{2b} & \multirow{2}{*}{110 kV} & \multirow{2}{*}{18 December 2006} & \multirow{2}{*}{DB-25\#} & \multirow{2}{*}{Karamay} & \multirow{2}{*}{Cycloalkyl} \\  & & & & & & & \\ \hline \multirow{2}{*}{\begin{tabular}{c} Xia Men \\ \end{tabular} } & \multirow{2}{*}{Wuli No.2} & \multirow{2}{*}{3b–4a} & \multirow{2}{*}{220 kV} & \multirow{2}{*}{18 September 2001} & \multirow{2}{*}{DB-25\#} & \multirow{2}{*}{Karamay} & \multirow{2}{*}{Cycloalkyl} \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \hline \multirow{2}{*}{\begin{tabular}{c} Fu An \\ \end{tabular} } & \multirow{2}{*}{Bingongchang No.1} & \multirow{2}{*}{1a–1b} & \multirow{2}{*}{Non-operation after detection as corrosive and the oil was} & \multirow{2}{*}{Paraffin base} \\  & & & & & returned oil & & \\ \hline \multirow{6}{*}{\begin{tabular}{c} Overhaul \\ \end{tabular} } & \multirow{2}{*}{Quanzhou No.1} & \multirow{2}{*}{2b} & \multirow{2}{*}{500 kV} & \multirow{2}{*}{29 March 1998} & \multirow{2}{*}{DB-25\#} & \multirow{2}{*}{JOMO} & \multirow{2}{*}{Paraffin base} \\  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \hline \multirow{6}{*}{\
\begin{tabular}{c} Xiamen No.1 \\ \end{tabular} } & \multirow{2}{*}{2b} & \multirow{2}{*}{500 kV} & \multirow{2}{*}{22 March 1999} & \multirow{2}{*}{DB-25\#} & \multirow{2}{*}{Kansasi} & \multirow{2}{*}{Cycloalkyl} \\  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \hline \multirow{6}{*}{
\begin{tabular}{c} Haicang No.1 \\ \end{tabular} } & \multirow{2}{*}{3a} & \multirow{2}{*}{500 kV} & \multirow{2}{*}{7 September 2007} & \multirow{2}{*}{10\#} & \multirow{2}{*}{Nynas} & \multirow{2}{*}{Cycloalkyl} \\ \cline{1-1} \cline{6-8}  & & & & & & & \\ \hline \hline \end{tabular}  
* The corrosive degree are categorized by the standard ASTM D130 (Standard test method for corrosiveness to copper from petroleum products by copper strip test).  
\end{table} 
Table 1: Investigation statistics of corrosive oil samples in Fujian power grid. The Shanghai Electric Power Research Institute once studied the relationship between the total sulfur content and the active corrosive sulfur in transformer oil. Three typical transformer oils were selected for experiments at four temperature levels. The results showed that the main form of active sulfur in transformer oil is bisulphide and mercaptan sulfur, and the content of elemental sulfur is very low. The content of mercaptan sulfur is lower than the minimum testing standard at low temperatures, while it can be detected when the temperature is higher. It indicates that one sulphide could be converted to another at high temperatures, and some non-corrosive sulfide may be converted to active corrosive sulfide.