With the Brazilian market to international industrial products, it is necessary to check the quality conformity of these products in order to protect the consumer, encouraging continuous quality improvement and promote competition between manufactures [1]. The Compact fluorescent lamps (CFL's or LFC's) are one of the several products that the National Institute of metrology, quality and technology (INMETRO) regulates the quality. One of the LFC's testing stages is to keep the LFC's supplied with electric power for a time period and after this period switch off the LFC's in according to a predefined schedule. The construction of the LFC's supplied circuit is done using semiconductors, and these electronics components can cause an undesirable effect (harmonics) in electrical network. These effects cause a variety of problems in driving, conduction and stabilization laboratory circuits. This paper presents an analysis and suggests a solution to the problem of energy quality in one of the laboratories accredited by INMETRO.