Re: Inductor question

Really what you want to know here is the quality of the inductor, the 'Q'
factor.

The bigger the Q, the better the inductor.

The basic equation for the Q factor is that the Q is proportional to the
inductor's reactance, and inversely proportional to its internal series
resistance.
The reactance is related to the frequency, the operating frequency, of the
inductor.

Thus the equation to figure out the Q factor is:

Q = XL / Ri

where 'Ri' is the series resistance of the inductor,
and
where 'XL' is the reactance, or XL = 2(pi)fL
     where f is the operating frequency, and L is the inductance in H, and
pi is 3.1415926blahblahblah.

So you can see that there is an inverse relationship between the Q and the
Ri of the inductor.
--The higher the Ri, the lower the Q.
--The lower the Ri, the higher the Q.

 From a practical standpoint, if the Q of an inductor is greater than about
100, then the internal resistance, Ri, is basically negligible since the
reactance would have to be more than a hundred times greater than Ri.

-Anders.

At 11:09 AM 10/17/00 -0400, Chris wrote:
>On Tue, 17 Oct 2000, Christopher X. Candreva wrote:
>
> > 830 mA, .29ohm, 1.0uH
> >
> > I've never speced an inductor, but from theory you would ideally want
> it not
> > to have any resistance. So the current rating should be a minimum, a LOWER
> > ohm rating would be OK, and obviously the correct number of uH .
>
>To clarify, I am saying that the replacement should be rated at LEAST 830mA,
>and at MOST .29 ohm.
>
>Am I correct ?

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Received on Thu Oct 19 11:44:34 2000