TEC is an employee-owned company based in Knoxville, Tennessee, USA, that designs and manufactures diagnostic instruments for four diverse industries. These industries are represented by TEC's four divisions: Aviation, also known as ACES Systems; Materials Testing; Nuclear Power; and Electric Power, or Powermetrix. AVIATION - The combination of experience and reputation in the industrial world provided TEC with a natural entry into the world of aircraft maintenance and condition monitoring equipment. ACES Systems' instruments are used worldwide as on-wing ground support maintenance equipment and in engine manufacturers' test cells and overhaul facilities. These instruments are used for many aircraft maintenance applications including measuring engine vibration and noise levels, monitoring and trending turbine engine performance, and performing dynamic balancing. MATERIALS TESTING - In 1984, TEC began designing and manufacturing residual stress analysis systems--instruments that use x-ray diffraction to analyze the surface of metal and ceramic components for stresses that occur during manufacturing, reworking or operation of the part. NUCLEAR - TEC was founded in 1975 and quickly became known in the industry for its quality design and manufacturing of monitoring systems for nuclear power production companies. TEC's Nuclear Products Division continues to serve the nuclear industry today. ELECTRIC POWER - In 1998, TEC further expanded its expertise in monitoring and analytical instruments with its acquisition of Powermetrix Corporation. Now called the TEC Powermetrix Division, this division designs and manufactures electric power measurement instruments for the power industry.