Capacitance Measurement Accuracy - IET Labs, Inc. RLC Digibridge 1693 User And Service Manual

1693 RLC Digibridge
HACS-Z
Setting
10 pF
100 pF
1500 pF
1500 pF
1500 pF
6400 pF
10 nF
25 nF
25 nF
25 nF
100 nF
200 nF
400 nF
400 nF
400 nF
1000 pF
* These ranges of acceptable displays are based on specified accuracy of decade capacitor that has recently been calibrated.
If the capacitor values are known to higher accuracy by special calibration of lesser accuracy because of long-term drift, the
acceptable upper and lower limits must be revised accordingly.
** Based on the stated dissipation values of the HACS-Z capacitors, If the dissipation values are known more accurately, the
acceptable QDR display criteria can be reduced accordingly.
Alternative capacitance standards are available for checking the Digibridge. Models available from IET include:
1413 Precision Decade Capacitor
SCA Series
5.8.3 Capacitance Measurement
Accuracy
This procedure follows after paragraph 5.8.2. (Leave
the test frequency at 1 kHz, the test voltage at 1 V, the
measure rate SLOW, the selected parameter Cs/D, and
the RANGE HELD indicator NOT lit.)
1. Connect the 1657-9600 extender cable (with
banana plugs) to the Digibridge test fixture.
Hand-tighten the screws, to provide the
ground (guard) connection.
2. Connect the "high" leads (red and red/white)
together. Separately connect the "low" leads
(black and black white) together.
132
Measure
Accuracy Range
Rate
5.05% 1 SLOW
0.55% SLOW
0.083% SLOW
0.083% MED
0.083% FAST
0.058% SLOW
0.055% 2 SLOW
0.052% SLOW
0.052% MED
0.052% FAST
0.051% SLOW
0.05% 3 SLOW
0.05% SLOW
0.05% MED
0.05% FAST
0.05% SLOW
Table 5-6: Capacitance accuracy checks (Ranges 1-3)
1693 Digibridge
Lower Upper
Accuracy
Limit* Limit*
0.22% 9.4730 10.527
0.04% 99.410 100.59
0.021% 1498.4 1501.6
0.053% 1497.9 1502.1
0.128% 1496.8 1503.2
0.020% 6395.0 6405.0
0.020% 9.9925 10.008
0.020% 24.982 25.018
0.050% 24.974 25.026
0.120% 24.957 25.043
0.020% 99.929 100.07
0.020% 199.86 200.14
0.020% 399.72 400.28
0.050% 399.60 400.40
0.120% 399.32 400.68
0.020% 999.30 1000.7
3. Before measurement, zero the Digibridge
as follows:
A. Leave the high (red) banana plug stack
disconnected from the low (black) stack
B. Press [FUNCTION] key (if necessary) to
select MEASURE.
C. Press [MEASURE MODE] key (if neces-
sary) to select TRIGGERED mode.
D. Press the following keys: [1] [6] [9] [3] [=]
[SHIFT] [OPEN].
E. Confirm that the GO indicator is lit.
F. Keep hands and objects at least 10 cm
(4 in.) from test fixture,
G. Press the START button.
H. Wait for the GO indicator to be lit. The
RLC display should be .000000 pF.
I. Connect the two banana plug stacks to-
gether; leave the guard (black/green) open.
J. Press the following keys: [1] [6] [9] [3] [=]
[SHIFT] [SHORT].
QDR
Max**
6100 ppm
2500 ppm
700 ppm
1000 ppm
1700 ppm
500 ppm
500 ppm
500 ppm
800 ppm
1500 ppm
500 ppm
600 ppm
600 ppm
900 ppm
1600 ppm
600 ppm
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