Abstract: To address the difficulties associated with power outages caused by the protection retrofit of 10kV single-source distribution lines, this study investigated a non-power outage protection retrofit technology based on external temporary protection substitutes. It analyzed the differences between non-power outage and power outage retrofit models, the functional circuit design of temporary protection devices, operational procedures, and key risks. Combined with practical engineering applications, the study evaluated the effectiveness and value of the non-power outage retrofit technology, providing a new technical solution for the protection retrofit of 10kV distribution lines.