Fluke 5790A, Руководство оператора

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5790A
Operators Manual
E-4
Note
With internal sensing on the millivolt ranges, capacitive loading causes an
increase in the 5200A output in the 100-kHz to 1-MHz range. This increase
in output is due to external capacitance being placed in parallel with
internal inductance, resulting in a parallel tuned circuit. The nominal
calibration is at the end of the 1-foot cable with 36-pf capacitance load.
The 5790A input capacitance is 64 pf, causing a 0.08 % increase in the
output at 1 MHz. Subtract this error from the 5790A error reading before
applying the test tolerance. Calculate errors at other frequencies by using
the equation in Table F-3.
Table F-3. Millivolt Ranges Output Accuracy Tests Tolerances
Voltage/Frequency Ranges
Output/Range
10 Hz - 30 Hz
(0.1% + 10
μ
V)
30 Hz - 20 kHz
(0.02% + 10
μ
V)
20 kHz - 100 kHz
(0.05% + 20
μ
V)
0.1 MHz - 1.0 MHz
(0.33% + 30
μ
V)
100 mV /100 mV range
10 mV/10 mV range
1 mV /1 mV range
±
0.11 %
±
0.2 %
±
1.1 %
±
0.03 %
±
0.12 %
±
1.02 %
±
0.07 %
±
0.25 %
±
2.05 %
±
0.36 %*
±
0.63 %
±
3.33 %
* Subtract the following capacitance loading error from the measured readings before comparison to the
test tolerance:
5790A cap loading error in % = 0.08 (f MHz)2
(1 MHz)
6. Connect the equipment as shown in Figure F-4.
7. Set the 5200A output to 10 mV on the 10-mV range at 1 kHz.
8. Set the reference voltage of the 5790A to give a direct error read-out as follows:
a. Set the MODE switch to OPR.
b. Adjust the 5200A output voltage if necessary to give the exact reading of
10.0000 mV (
±
2 counts) and push the SET REF soft key on the 5790A.
c. Push the soft key under the error display units to give PCT.
d. Reset the 5200A to 10 mV.
ff4.bmp
Figure F-4. 10 mV Output Accuracy Equipment Configuration