Abstract: To address issues such as poor adaptability of short-circuit line length, cumbersome storage and usage, and on-site management risks in power equipment maintenance and testing, this paper designs a transformer short-circuit test device that integrates automatic winding and unwinding with anti-retraction functionality. The device features a core body with two independent winding mechanisms symmetrically arranged internally, utilizing torsion springs to provide rebound force for automatic short-circuit line winding. It adopts a ratcheting interlocking brake structure to ensure positional stability after line extension, and incorporates a button-controlled rapid separation mechanism for manual one-touch winding. Practical applications show that this device effectively resolves material waste, low operational efficiency, and safety hazards associated with traditional short-circuit line usage, providing a reliable and efficient specialized tool for maintenance and testing tasks.