Agilent Technologies 16451B, Руководство по эксплуатации

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Compensation Result Example
If the measured capacitance values are 227.6 pF , 185.2 pF and 156.58
pF , when the set values of the micrometer are 40 m, 50 m, and 60
m. Each theoretical capacitance values and equivalent electrode
distance errors are listed in T able 3-11 .
T able 3-11. Compensation Result Example
t
set
[m] C
m
[pF] C
t
[pF] 1t
e
[m]
40 227.60 252.48 4.4
50 185.20 202.11 4.6
60 156.58 168.51 4.6
So , the average of equivalent electrode distance error is obtained as
follows:
1t
a
=
4: 6 + 4: 6 + 4: 4
3
' 4: 5 [m]
In this case , the equivalent electrode distance is as follows:
t
eq
= t
set
+ 4: 5 [m]
Use the equivalent electrode distance (t
eq
) to accurately calculate
accurately the dielectric constant
r
.
Eective Area of Electrode
This error is included in capacitance values measured C
s1
and C
s2
. It
is caused by the stray capacitance at electrode's edge even though
a guard electrode is used. T o reduce the error , divide capacitance
value C
s1
and C
s2
by eective area constants
a
and
b
as shown in
following equation.
r
=
1
1 0 1 0
C
s 1
C
s 2
2
b
a
2
t
eq
t
a
Where , t
eq
is the equivalent electrode distance . F or more information,
refer to \Eective Area of Electrode " in \Error F actor using
Contacting Electrode Method" and \Gap Error".
3-64 Operation