How to inspect and repair inductors?
The magnetic rod inductors or magnetic loop inductors in the circuit board are mainly used in various power supply circuits. The magnetic rod/magnetic ring inductor can be measured with a digital multimeter or a pointer multimeter. For accurate measurement, the inductor can be measured with an open circuit.
Use a digital multimeter to detect the inductor in the circuit board:
(1) First, disconnect the power supply of the circuit board, and then observe the magnetic bar inductor to be tested to see if the inductor is damaged, whether it is burnt, soldered, or the coil is deformed. If there is, the inductor has been damaged. The figure below shows a magnetic bar inductor to be tested.(2) If the appearance of the magnetic rod inductor to be tested is not damaged, solder the magnetic toroidal inductor to be tested from the circuit board with an electric soldering iron, and clean the pins at both ends of the magnetic toroidal inductor, and clean the remaining pins on both ends The dirt, to ensure the accuracy of the measurement. The desoldering method of the magnetic bar inductor is shown in the figure below.
(3)Turn the digital multimeter to the "200" block of the ohm block.
Since the measured resistance of the magnetic bar inductor is very close to 00.0, it can be judged that the inductor has no open circuit fault. Then select the "200M" gear of the multimeter to detect the resistance between the coil lead of the inductor and the iron core, and between the coil and the coil.
Under normal circumstances, the resistance between the coil lead and the iron core, and between the coil lead and the coil lead is infinite, that is, the dial of the digital multimeter should always display "1" during measurement.
It has been tested that the magnetic bar inductor has good insulation and no leakage.