Fluke 5790B, Руководство по обслуживанию

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Calibration Adjustment and Verification
Calibration Verification
3
3-51
Verifying Absolute AC Error for Region V (2.2 mV through 22 mV)
For the 7 mV through the 22 mV ranges, use a bootstrapping technique. After
you verify the 70 mV range, apply each test voltage and frequency to both the
verified range and the range under test. Accept the reading on the verified range
after showing that it is operating within specifications. Step down through the
ranges as described in the calibration procedures and shown in Figure 3-9 until
the 2.2 mV range is verified. On each range tested, use the following formula and
enter the results in Table 3-12.
AC
err
= AC
DUT_R
- AC
DUT_Ver_R
AC
Nominal
* 10
6
- AC
DUT_Ver_Err
- AC
DUT_Ver_R_Linearity_Err
( (
Where,
AC
err
is the final result for the amplitude/range under test measured in µV/V.
AC
DUT_R
is the mV measurement of the DUT in the range being verified.
AC
DUT_Ver_R
is the bottom scale mV measurement of the DUT in the upper range.
AC
Nominal
is the nominal in mV
AC
DUT_Ver_R_Err
is the measurement error of the upper range from which we
bootstrap in µV/V
AC
DUT_Ver_R_Linearity_Err
is the measured range linearity error in µV/V.
AC
DUT_Ver_R_Linearity_Err
= AC
DUT_Ver_R_1/2Scale_Err
- AC
DUT_Ver_R_FullScale_Err
Where linearity of the upper range is based on measurements with 100:1
resistive divider relative to Fluke 792A. Components are all in µV/V relative to
Fluke 792A and use of 100:1 resistive divider during both steps.
If Wideband option is not present, proceed to the
Update Full Verification Date
section. Otherwise proceed with Verifying the Wideband AC Option .