1-4
1.5.4 Humidity verification equipment
Table 1-4 summarizes test equipment recommended to ver-
ify the accuracy of the Model 6517A humidity measurement
function.
1.6
Verification limits
The verification limits stated in this section have been calcu-
lated using only Model 6517A one-year accuracy specifica-
tions, and do not include test equipment uncertainty. In cases
where the Model 6517A apparently does not meet its pub-
lished specifications based on stated reading limits, reading
limits should be recalculated using both Model 6517A accu-
racy specifications and the total absolute uncertainty of the
verification equipment.
Reading limit calculation example
As an example of how reading limits can be calculated using
test equipment uncertainty, assume that the 200µA range is
being tested using a 190µA input value, and the various spec-
ifications are as follows:
Table 1-4
Humidity verification equipment
Mfg.
Model
Description
Specifications*
Fluke
5700A DC voltage calibrator 0V, 0.5V, 1V,
±5ppm basic
accuracy
Banana plugs to clip
leads
2, 1 in. lengths of
solid #20AWG wire
* DC voltage calibrator with better than 0.25% basic accuracy may be
substituted.
• Model 6517A 200µA range one-year accuracy: ±(0.1%
of r 5 counts)
• Calibrator total absolute uncertainty at 190µA output:
±103ppm
The calculated limits are:
Reading limits = 190µA ± [(190µA
×
0.1% + 0.005µA) +
(190µA
×
103ppm)]
Reading limits = 190µA ± 0.21457µA
Reading limits = 189.7854µA to 190.2146µA
1.7
Restoring default conditions
Before performing
each
performance verification procedure,
restore instrument bench default conditions as follows:
1. From the normal display mode, press the MENU key.
The instrument will display the following:
MAIN MENU
SAVESETUP COMMUNICATION CAL
2. Select SAVESETUP, and press ENTER. The following
will be displayed:
SETUP MENU
SAVE RESTORE POWERON RESET
3. Select RESET, and press ENTER. The display will then
appear as follows:
RESET ORIGINAL DFLTS
BENCH GPIB
4. Select BENCH, then press ENTER. The following will
be displayed:
RESETTING INSTRUMENT
ENTER to confirm; EXIT to abort
5. Press ENTER again to confirm instrument reset. The
instrument will return to normal display with bench
defaults restored.