On this day 30 years ago, on July 2, 1995 (June 5, 1995 in the lunar calendar), Guangdong Daya Bay Nuclear Power Plant was re-connected to the grid. On July 2, 1995, the No. 1 unit of Guangdong Daya Bay Nuclear Power Plant completed the first refueling overhaul, and was re-connected to the grid at 16:21 to generate electricity. Unit 1 was shut down as planned in mid-December 1994 for the first refueling overhaul. After the overhaul work was completed at the end of February this year, a series of rigorous re-appraisal tests were carried out. It was found that a few control rods had dropped more than the acceptance criteria. It was decided to check and deal with them. After joint investigation and analysis by Chinese and French experts and confirmation by the manufacturer Famatom Company, the root cause of the above problems was the design problem of the guide tube. To this end, Famatom provided new guide tube spare parts and replaced the guide tube with excessive drop time. The unit reached the hot shutdown state on June 28, 1997, and the drop time test was carried out again. The results all met the acceptance criteria. After being reviewed and approved by the National Nuclear Safety Administration, Unit 1 reached criticality at 5:40 am on June 30 and was re-integrated into the power grid at 16:21.