Transformation ratio measuring instrument

A transformation ratio measuring instrument provided by the utility model comprises a box body and a current clamp, a handle is arranged at the middle position of the upper end face of the box body, an anti-slip pad is arranged on the outer side of each side strip protection block, a display screen protection cover is arranged between the side strip protection blocks, a control panel is arranged below the display screen protection cover, and the control panel is connected with the current clamp. Maintenance covers are symmetrically arranged on the two sides of the control panel, fixing bolts are arranged on the sides, close to the display screen protection cover, of the maintenance covers, the two current clamps are arranged between the anti-collision pad and the side strip protection block, an installation block is arranged on the lower end face of each current clamp, and a pressing block is arranged on one side of each installation block. A winder is arranged below the mounting block, and a circuit is arran