Inductance tolerance
Oct 18, 2019| Stay Charging Safely with SChitec
Inductance tolerance
The allowable deviation is the allowable error between the nominal inductance and the actual inductance on the inductor.
Generally, inductors used in circuits such as oscillation or filtering require high precision, and the allowable deviation is ±0.2%~±0.5%. The accuracy of coils for coupling and high-frequency choke is not high; the allowable deviation is ±10. %~15%.
The quality factor, also known as the Q value or the figure of merit, is the main parameter for measuring the quality of the inductor.
It refers to the ratio of the inductive reactance exhibited by the inductor to its equivalent loss resistance when operating at an AC voltage of a certain frequency. The higher the Q value of the inductor, the smaller the loss and the higher the efficiency.
The quality factor of the inductor is related to the DC resistance of the coil wire, the dielectric loss of the coil bobbin, and the loss caused by the core and the shield.
The distributed capacitance refers to the capacitance between the turns and turns of the coil, between the coil and the core, between the coil and the ground, and between the coil and the metal. The smaller the distributed capacitance of the inductor, the better its stability. The distributed capacitance can make the equivalent energy dissipation resistance larger and the quality factor becomes larger. Reduce the distributed capacitance commonly used wire wrapped wire or stranded enameled wire, sometimes also using cellular winding method.
Rated current
The rated current is the maximum current that the inductor can withstand under the allowable working environment. If the operating current exceeds the rated current, the inductor will change its performance parameters due to heat generation, and even burn out due to overcurrent.