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But it's not a resistor at that frequency

M0DCD
Could someone answer why the manufacturers of wire wound resistors, or indeed any other types, don't quote the self inductance figures for their parts. Even in applications such as SMPSU, the switching frequency may be enough to make this a significant feature of its performance in the circuit. Some of the low resistance value ones, such as the Welwyn W21 series do work much better as RF chokes than some supposedly purely inductive components.
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    Hi Andrew,

     

    You're absolutely right that wirewound resistors make good inductors - indeed in some transient suppression applications it's actually an advantage. They are essentially single layer windings on a low relative permeability core, so can't really compete with purpose built inductors in terms of self inductance per unit volume, but the effect can be important. You'll seldom find details of parasitic reactances on resistor datasheets, but the data is often available. For example, you'll see from the data for W20 series (attached) that inductance increases with body size /rating and is roughly proportional to ohmic value.

    Attachments:
    imageW20 Inductance.pdf