Independent Laboratory Services edicated to the Electrical Power Industry
Timely and effective lab services !
Dissolved gas analysis is probably the most widely used preventative maintenance technique in use today to monitor the operation of transformers. Properly used it can be a powerful tool in a well disciplined maintenance program. Depending on the location of a transformer and the nature of its usage, an appropriate dissolved gas analysis schedule can be set up.
NTT performs tests according to standards approved by the American Society for Testing and Materials (ASTM). These tests are designed to evaluate the ability of the oil to perform its job. Tests include 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.
The EPA has classified electrical equipment and insulating fluids according to the level of PCB contamination. The EPA’s classifications of equipment and fluids are shown in the table below. Regulations set forth by the EPA have made it cost effective to determine the level of PCB contamination prior to disposal of eqipment or fluids. Delays caused by slow laboratory service may leave a repair shop idle while wating for PCB test results. Inaccurate determination can lead to an unnecessary increase in disposal costs. Prompt, reliable results are mandatory for PCB analysis.