The CB system (IEC system for conformity testing and certification of electrical products) is an international system operated by IECEE. The certification bodies of IECEE member countries test the safety performance of electrical products based on IEC standards. The test results are the CB test report and CB The test certificate is a system recognized by each member of IECEE. The purpose is to reduce the barriers to international trade arising from the need to meet the certification or approval criteria of different countries. IECEE is the abbreviation of the International Electrotechnical Commission's organization for conformity testing and certification of electrical products.