Current sense transformers are used to detect and measure current. There are two basic types of products: switch-mode transformers for power conversion applications, and precision-measurement transformers for instrumentation applications. Current sense transformers for power conversion applications are used to measure trends, peak values and average values rather than absolute values. These devices are efficient and dense, but do not offer a great amount of accuracy. They are available in a variety of shapes and styles, and are can support most traditional manufacturing processes. Current sense transformers are certified and approved by the American National Standards Institute (ANSI), the Canadian Standards Association (CSA), the International Electrotechnical Commission (IEC), Underwriters Laboratories (UL), TÜV Rheinland/Berlin-Brandenberg (TUV), and Verband Deutscher Elektrotechniker (VDE). Products sold in European Union (EU) nations must comply with the Restriction of Hazardous Substances (RoHS) and Waste Electrical and Electronics Equipment (WEEE) directives.

