Inductive vs. Non-Inductive Resistors


The induction of a resistor is a very important item to keep in mind when building a circuit, especially if you are dealing with switching or high frequency circuits. The construction of most resistors are very similar to that of an inductor. They take a specific length of wire or film, determined by the resistance value they are trying to achieve, and wrap it around a core made of ceramic, plastic, fiberglass, or another non-conductive material. A non-inductive resistor is wound one way then again in the other direction, as shown below. This will cancel out the magnetic fields generated by each of the wires.

Most resistors are created in this same manner but with different materials. For example, film based resistors are using film instead of wire which has proved to be more precise. Ceramic and carbon composition, not to be confused with carbon film, are naturally non-inductive because they don’t have any windings.

A non-inductive resistor can be used to replace an inductive resistor, but that might not be a realistic goal. Inductive resistors are typically cheaper to construct and are more commonly made with higher power ratings.

DC circuits don’t have to worry about the inductance of a resistor since there isn’t any fluctuation in the current to create the altering magnetic fields.

Resistors that have been specifically constructed to be non-inductive will be labeled as such under the Features filter on our website.

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