Compared with the traditional oil-immersed light test transformer, the YDQW series gas-filled non-partial discharge test transformer has a weight reduction of 40-65% (depending on the voltage and capacity level), and there is no oil pollution. The voltage level of a single test transformer can reach 300KV. Due to the new production process, the technical performance of the product has been greatly improved, and it is especially suitable for field work and frequent moving working conditions.