Re: Calculating inductance...

To: tesla-at-pupman-dot-com
Subject: Re: Calculating inductance...
From: Steve Roys <sroys-at-umabnet.ab.umd.edu>
Date: Sun, 19 May 1996 13:24:38 -0400 (EDT)

On Fri, 17 May 1996, Tesla List wrote:

> Z is AC current? (as in V = IR)

Z is the complex impedence or reactance - the analog of resistance for 
inductors and capacitors.  The impedence of a inductor or capacitor is 
frequency dependent.

For an inductor, Z = 2*pi*f*L as mentioned, f = frequence in Hz, L = 
inductance in H.  For a capacitor, Z = 1/(2 * pi * f * C) where f = Hz as 
before and C = capacitance in F.  Just like a resistor, V = I*Z

> What is a sense resistor?  Just a resistor of a known value?

Yes, so you know R and measure V to calculate I = V/R.

> I'll try it this weekend, and if I don't get a reply, I'll try it with the 
> assumptions above.  However, my volt meter is suspect, so I'll try
> to get it to read some roughly known values accurately.

Unless it's a VTVM, your meter will probably not read accurately at 
frequencies in the kHz and higher range.  It's more accurate to use your 
scope to check the voltages.

Steve Roys.