Abstract: The polarity detection of transformers is an important task to ensure the accuracy of electrical energy measurement. This article designs a new type of intelligent foot nail for preventing accidental climbing of transmission towers. The main structure includes three parts: the foot nail body, the main control box, and the data background. If a live tower is accidentally climbed, the sensor installed on the foot nail emits a signal, and then sends out a warning sound and the background reminds to avoid the occurrence of accidental climbing events.