Fluke 8508A, Руководство по обслуживанию

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Calibration and Verification
Performance Verification
3
3-31
To Calibrate at Spot Frequencies
Spot Calibration is available only when in AC Voltage function with Spot already
selected on the
ACV CONFIG
menu. Each spot (six per range) can be calibrated at a valid
input frequency to a non-nominal RMS value. In subsequent use, frequency response
flatness errors are reduced within ±10 % of the calibrated spot frequency.
Assuming that the Multimeter is in calibration mode and the setup is connected as
described above under Initial Setup and Connections for routine calibration. The
configuration defaults to
Tfer
and
RESL6
(both required).
Proceed as follows:
1.
Select
ACV
and select the required Range.
2. Press the
CONFIG
key and select
Spot
.
3. Press the
CAL
key.
The
CALIBRATION
menu is displayed.
4. Select
Set
.
The
SPOT CAL
menu is displayed.
5. Select the soft key for the required spot, 1 to 6 (
Sp1
to
Sp6
).
The SPOT (x = 1 to 6) RMS menu is displayed.
6. Key in the true RMS output value of the standard, then select
Enter
.
The
SPOT FREQUENCY
menu is displayed, showing the frequency at which the
spot will be calibrated.
7. Press
SAMPLE
to initiate the calibration operation.
Calibration is complete when the
Busy
legend goes out and the calibrated
measurement is displayed. The menu display reverts to the
SPOT CAL
menu.
8. On the Calibrator, set
STANDBY
.
9. On the Multimeter, select other spots as required, repeating the process for each
selection.
10. Exit from the
SPOT CAL
menu by pressing any hard key.
Performance Verification
The 8508A Digital Reference Multimeter offers state of the art performance. This
procedure is intended as a guide for qualified metrology personnel who have access to a
standards laboratory with equipment available to verify the performance of an instrument
of this level of accuracy. The procedure assumes users are familiar with relevant best
measurement practice, and will take precautions to avoid introducing errors from sources
such as thermal emfs, leakages, electromagnetic interference, etc. It also assumes users
will make adequate allowance for equipment stabilization and measurement settling
times.
This routine performance verification procedure describes the test points and sequence of
operations required to check the Multimeter and assumes calibration references of
adequate traceable uncertainty are available – in this case a Fluke 5720A calibrator and
5725A amplifier used with an 8508A-7000 Calibration Kit. The procedure assumes the
user is able to calibrate and characterize the calibration standards, without describing the
process required to do so. Refer to the Routine Calibration section for more information
on the characterization process.