TB 9-4931-405-40
(4) Record resulting value in table 4, section A, calculated calibrator output
(A) column.
(5) Repeat technique of (2) through (4) above for remaining calibrator nominal
outputs listed in table 4, substituting standard resistors as specified.
(6) Connect equipment as shown in figure 2.
(7) Insert TI plugs in .000015 AMPERES position. Set calibrator for a nominal
10 A dc output.
(8) Allow sufficient time for stabilization (1 to 3 minutes), then record new
multimeter dc voltage indication in table 4, section B.
(9) Transcribe calculated calibrator output data from section A to section B.
(10) Calculate resistance of .000015 AMPERES plug position using formula:
Multimeter dc V indication
Plug position
=
Calculated calibrator output (in A)
(11) Record resulting resistance value in table 4, Section B., calculated resistance
value column.
(12) Set plug positions as specified and repeat technique of (7) through (11) above for
remaining plug positions listed in table 3, Section B.
(13) Transcribe calculated resistance value from table 4, section B, to calibration test
report.
b. Adjustments. No adjustments can be made.
14. Calibration Test Report. Calibration test report is required for this TI. The purpose
of the test report is to allow utilization of:
a. Instruments whose values have drifted outside manufacturer's specifications when
referenced to nominal values, yet the drift rate is sufficiently low to allow use within
manufacturer's specified accuracy of the previous test report value.
b. Instruments that have values and stability better than manufacturers specifications
may be utilized at greater accuracies when test report values are used. The performance
specifications shall be ascertained by referencing present measured values to previous
measured values, in lieu of present to nominal values. If present measured values are not
within manufacturer's accuracy specifications of last measured value, the TI must be red-
tagged. Calibration activities will maintain a case history file of test reports for the TI.
The file will contain an accumulation of at least six of the most recent test reports. If, in
four successive calibrations, the measured value drifts from the nominal value as much as
three times the manufacturer's accuracy specification, the TI must be red-tagged. An
example of calibration data to be annotated on the test report is shown on the sample test
report.