Predictive oil analysis.
• There are five tests available to maintenance engineers, which are widely recommended since when conducted together, they offer a precise diagnostic of the oil’s operating conditions. These are: dielectric rigidity, power factor, resistance, interfacial tension and acidity.

Dissolved gases Chromatography.
• The analysis of dissolved gases in oil is a useful tool for early detection of failures in transformers that could become permanent failures if not corrected in time.

Possible failures caused by Gas in the Oil.
• Halo-effect discharges.
• Overheating of cellulose.
• Overheating of cables.
• Oil arcing.

Oil maintenance tests: • Dielectric rigidity ASTM D 877 and D 1816: Indicates the ability o fan oil to support electrical forces without failure. • Power factor at 25°C and at 100°C ASTM D 924: Indicates dielectric losses.

• Resistance ASTM D1169: Indicates the resistance of oil to D.C. flow.
• Interfacial tension ASTM D2285: Determines the concentration of sludge particles.
• Acidity ASTM D974: Determines the deterioration of the oil due to acids formation.
• Humidity content ASTM 1533: Determines the amount of water dissolved in the oil, in PPM.
• Analysis of dissolved gases in the oil ASTM D3612: Determines the presence of combustible gases.
• Analysis of BPC’s content ASTM D 4059: Determines the content of Biphenyl Polychlorides (highly contaminant).