Fluke 8508A, Руководство по обслуживанию

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8508A
Service Manual
3-28
Table 3-7. AC Current Calibration Points and Sequence
8508A Range Point Current Frequency
Zero (5 % Range)
10
μ
A
300 Hz
200
μ
A
Range Gain
100
μ
A
300 Hz
Zero (0.5 % Range)
10
μ
A
300 Hz 2 mA
Range Gain 1 mA 300 Hz
Zero (0.5 % Range)
100
μ
A
300 Hz 20 mA
Range Gain 10 mA 300 Hz
Zero (5 % Range) 10 mA 300 Hz 200 mA
Range Gain 100 mA 300 Hz
Zero (5 % Range) 100 mA 300 Hz 2 A
Range Gain 1 A 300 Hz
Zero (5 % Range) 1 A 300 Hz 20 A
Range Gain 10 A 300 Hz
The procedure assumes the user has knowledge of the actual output value of the
calibrator at each point, from a measurement or from a certificate of calibration. The
Set
feature allows a user to enter the true output value of the calibration standard where it
differs from the nominal point. If the calibrator output is considered to be exactly
nominal, use of the
Set
feature is not required, also omit steps 3-5.
On each range, the Multimeter automatically recognizes the appropriate value as range
zero or range gain from the applied signal amplitude.
1.
On the Multimeter, select the required Range.
2. On the Calibrator select Output Current and Frequency, Operate.
3. On the Multimeter, Press
CAL
to revert to
CALIBRATION
menu.
4. Select
Set
on the
CALIBRATION menu
.
5. Use the numeric keys with the
SET VALUE
menu to key in the true output value of
the calibrator, then press Enter.
6. Press
SAMPLE
to initiate the calibration operation.
Calibration is complete when the
Busy
legend goes out and the calibrated
measurement is displayed.
7. On the Calibrator, set Output to
STANDBY
.
8. On the Multimeter, press
ACI
key to revert to the ranges menu.
Frequency Calibration
The Multimeter frequency calibration operation requires a signal at exactly 1MHz (
Set
is
not available on the Multimeter for frequency calibration). If the calibrator frequency
output is not exactly nominal or sufficiently close to nominal it may be phase locked to
an external reference frequency at the required output frequency applied to its rear panel
phase lock input, for example from a laboratory frequency standard or off-air reference
receiver. If used, the calibrator should be disconnected from the frequency reference and
phase locking disabled before attempting any other calibration operations with the
calibrator.