On-load tap-changer online oil purifier is a product with independent intellectual property rights independently developed by our company's technical personnel based on the principle of precision filtration. The transformer oil containing impurities is filtered through the two-stage filter, and then enters the on-load tap-changer oil chamber through the gear pump to avoid the impact of impurities on the gear pump caused by blocking, wear too fast, and excessive dry sound. The machine realizes the flexible control of timing start by multi-function time control switch.