bz transformer oil regenerator series utilizing physical chemistry methods recover deteriorated transformer oil and switch oil while removing the acid, suspended particles and precipitated residua in oil. it utilizes a special purification agent, which can work while transformer still running properly. the basic contents and anti-oxygenic property of oil remains the same after treatment, and can be back to the specifications of new oil; insulation performance and safety of equipment are enhanced while cost is reduced by 90% compared with conventional way of oil-change. it is recommended to use the recycling device after oil breakdown voltage is recovered to an acceptable degree in this case cost will be even lower and its effect will be more evident.