Agilent Technologies 4263B - Selecting Circuit Model for Inductance Measurement; Small Inductance Values; Large Inductance Values; Inductance Circuit Model Selection

4263B
Selecting
Circuit
Model
for
Inductance
Measurement
The
following
description
gives
some
practical
guide
lines
for
selecting
the appropriate
inductance
measurement
circuit
model.
Small
Inductance
V
alues
F
or
low
values
of
inductance
the
reactance
is
typically
small so
Rs is
more signicant.
Therefore
,
the
series
circuit
model
(Ls-D,
Ls-Q, or
Ls-Rs) is
appropriate.
(Refer
to
Figure
7-3
(a).)
Large
Inductance
V
alues
Conversely
for
large
inductances
,
the
reactance is
typically large
,so
Rp becomes
more
signicant
than
Rs
.
So,
a measurement
in the
parallel
circuit
model
(Lp-D
,
Lp-Q,
or
Lp-G)
is
more
suitable
.
(Refer
to Figure
7-3 (b).)
Figure
7-3.
Inductance
Circuit
Model
Selection
The
following
are
rules
of
thumb
for
selecting
the
circuit
model
according
to
the
reactance of
the
inductor
.

Above
approx.
10
k
:
Use
the
parallel
circuit
model

Below
approx.
10

:
Use
the
series
circuit
model

Between
above
values
:
F
ollow the
manufacturer's recommendation
F
or
example
,
to
measure
a1
 H
inductor at
1kHz
(reactance
is
approximately
6.3
m),
the
series
circuit
model
is
suitable
.
Impedance Measurement Basics 7-5