COMMON DIELECTRIC FLUID TESTS
Our experts routinely perform a complete series of diagnostic tests to optimize the health and long-life of your transformers and electrical equipment, including:
Dielectric Breakdown Testing
These tests assess the ability of the fluid to withstand electrical stress without breaking down. They measure the breakdown voltage, which can indicate contamination, degradation of insulation, and even moisture content.
Moisture Analysis
Determines the amount of moisture in the fluid. Moisture is detrimental as it reduces the dielectric strength and accelerates insulation aging.
Dissolved Gas Analysis (DGA)
Identifies the presence and types of gases dissolved in the fluid, which can indicate overheating or electrical discharges within the equipment.
Interfacial Tension
Measures the tension at the oil-water interface, with a decrease indicating oil degradation and increased contaminants like oxidation products and polar substances.
Color Number & Visual
The test is an indicator of fluid quality. Higher color number values indicate the probability of contamination or deterioration of the fluid. The visual test will also indication contamination in the fluid.
Liquid Power Factor
Measures the insulating quality and purity of the oil by assessing its dielectric losses under an AC field. A low power factor indicates good, clean, and dry oil, while an increasing power factor signifies moisture, oxidation, or other contaminants, signaling a need for maintenance, filtering, or replacement.
Neutralization Number (Acid)
Measures the acidity of insulating oil, typically by titration with a potassium hydroxide (KOH) solution. A low neutralization number is desirable, as excessive acid can degrade the transformer’s insulation and shorten its lifespan.
Specific Gravity
Measures the density of the oil relative to water, providing insights into its purity, type, and potential contamination by other fluids or water.
Oxidation Inhibitor Content
Measures the concentration of antioxidant additives in the oil to ensure the oil’s longevity and the transformer’s operational reliability.
Metals-in-Oil
Dissolved metals such as copper, iron, aluminum, and lead can indicate specific fault types and locations, complementing other tests like Dissolved Gas Analysis and electrical tests.
Furan Analysis
By measuring furan levels, companies can understand the extent of the cellulose breakdown, estimate the remaining life of the paper, and predict potential failures, allowing for timely maintenance or replacement decisions.
PCB Analysis
Determine the levels of polychlorinated biphenyl contamination in the dielectric fluid.