Abstract: The measurement of capacitance and dielectric loss factor of capacitive voltage transformers (CVT) is the most effective method to reflect their healthy operation status. As a commonly used measuring instrument, the dielectric loss tester features excellent measurement accuracy and sensitivity. However, affected by various factors including equipment grounding conditions, the number of voltage-dividing capacitors, and differences in secondary terminals, the test wiring methods are complex and varied. This paper analyzes the test scenarios of different voltage levels, draws the schematic diagrams and equivalent circuits of various wiring methods by combining the working principle of the dielectric loss tester, provides theoretical guidance and practical reference for on-site test personnel, ensures the accuracy of test wiring, and offers technical support for the state assessment and diagnosis of power equipment.