How are inductors rated?

Often have net friend to ask: how is inductance rated?In response to this question, Chinese inductance manufacturers answer from the following three aspects:

What is the rated current of an inductor

How to specify the rated current

There are two reasons for the rated current

What is the inductance rating?

Rated current is the maximum current allowed to pass through the inductor when it is in normal operation.Rated current is generally expressed in letters and printed directly on the inductor.In use, the actual working current of the inductor must be less than the rated current, otherwise the inductor coil will be seriously heated or even burned out.

How to specify the rated current?

Rated current represents the maximum amount of current that can flow continuously through the inductor.If you exceed this value, the heat will be too large to guarantee the mass.

In addition to the heating requirement, some products have rated current requirements based on changes in inductance.Specific content please refer to the specific specifications of various products.

Why are there two kinds of rated current of power inductors?

There are two reasons for rated current:

The rated current of power inductor has two kinds of determination methods: "the rated current based on the rise of self temperature" and "the rated current based on the rate of change of the value of inductance".Rated current based on self-temperature rise "is the rated current specified by the calorific value of the component. Use beyond this range may cause component damage and component failure.

At the same time, "rated current based on the rate of change of the inductance value" is the rated current stipulated by the decreasing degree of the inductance value. If used beyond this range, the IC control may be unstable due to the increase of ripple current.

In addition, the tendency of saturation (that is, the decreasing tendency of inductance) varies according to the magnetic circuit construction of inductors.Figure 1 is a schematic diagram showing the changes in inductance caused by different magnetic circuit configurations.For the type of open magnetic circuit, with the increase of dc current, the inductance value is relatively flat until the specified current value, but the inductance value drops sharply with the specified current value as the boundary value.In contrast, as the dc current increases, the value of the transmittance decreases, so the inductance decreases slowly.

That's how the inductor is rated;We are the inductance manufacturer, the product has:fixed inductor,smd inductor;Welcome to consult ~