Products using LEDs are being actively developed, thus there has also been a great demand for LED products that can replace traditional lamps, such as fluorescent lamps and metal halide lamps. But so far there is no proper standard that a manufacturer can use to test their products. As a result manufacturers cannot develop retrofit LED lamps and sell them even if they have the technology. In this study, by analysing the control gear for a fluorescent lamp that is currently used in the market, which is a magnetic or electronic ballast, this study tries to develop a proper test method by investigating the compatibility between an all-type control gear and LED retrofit products.