Detecting shorted turns with a standard LCR meter can be difficult because the impedance may change very little. A more reliable method is the Ring Test technique, commonly used for servicing transformers, flybacks, motors, deflection yokes, magnetic heads, and other inductive components.
To use the Ring Coil Tester with the LCR-Reader-MPA/MPB, connect the Coil Ring Tester attachment to the micro-USB port and attach the coil to the hook connectors. Push joystick to the left when in the “Frequency” menu and select “Winding Turns” . The display will show the coil response after excitation.
A good coil produces several decaying oscillations, while a coil with a shorted turn shows heavy damping with only 1–2 cycles. This method is based on the resonant response of a coil-capacitor circuit to a pulse excitation, where shorted turns significantly increase losses and reduce oscillation duration.