NTT performs tests according to standards approved by ASTM International, the international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services including the Electrical Power Industry.
Dissolved Gas Analysis – DGA
DGA has now become a standard in the utility industry throughout the world and is considered to be the most important oil test for insulating liquids in electrical apparatus.
Oil Quality Assessment
NTT performs a variety of tests designed to evaluate the ability of the oil to perform its job and to monitor operational conditions. Tests include dissolved gas analysis, moisture in oil, interfacial tension, acid number, color number, visual, dielectric strength, viscosity, specific gravity, power factor at 25oC & 100oC, oxidation inhibitor, refractive index, pour point, and flash point.