NTT DIAGNOSTICS FOR MINERAL OIL

Rogers' Ratios
The advantages to any ratio method are that they are quantitative and independent of transformer oil volume. However, ratio methods can produce incorrect interpretations or none at all. Therefore they should be used in conjunction with other diagnostic methods such as the key gas method. Additionally minimum levels of gases must be present before results of the ratio methods become significant.

Enter PPM values

Hydrogen H2

Methane CH4

Ethane C2H6

Ethylene C2H4

Acetylene C2H2

Carbon Monoxide CO

Carbon Dioxide CO2

Nitrogen N2

Oxygen O2

Diagnostics

CH4/H2 Code=

C2H6/CH4 Code=

C2H4/C2H6 Code=

C2H2/C2H4 Code=

CO/CO2 TCG=