NAVAIR 17-20AQ-347
7
SECTION 4
CALIBRATION PROCESS
NOTE
Unless otherwise specified, verify the results of each test and take corrective action whenever the test
requirement is not met, before proceeding.
4.1 DIRECT VOLTAGE TESTS
4.1.1 Zero Tests
4.1.1.1 Connect a low thermal short to the TI HI and LO terminals. Depress the TI ZERO pushbutton. Wait until the TI
BUSY light is extinguished. Depress the TI DCV pushbutton, and depress the RANGE pushbutton to select from the TI RANGE
listed in the following table, one range at a time.
4.1.1.2 Verify that the TI indication is within the tolerance limits listed in the following table.
TI RANGE
Nominal
(V)
Tolerance Limits
(V)
100
mV
0.0000
-3
-0.0090
-3
to +0.0090
-3
1
V
0.000000
-0.000009
to
+0.000009
10 V
0.00000
-0.00009 to +0.00009
100
V
0.0000
-0.0009
to
+0.0009
1
kV
0.000
-0.009
to
+0.009
4.1.1.3 Disconnect the low thermal short from the TI INPUT HI and LO terminals.
4.1.2 Establish Reference Voltage. Referring to Figure 1, set the DV source power switch to OPR. Adjust the controls of the
DV source and the null detector, as necessary, to obtain a reference null on the null detector. The DV source output indication at
null should be approximately 22 V.
4.1.3 Taking precautions, disconnect the ERS (item 2.1.5) and the null detector from the reference setup. Connect the TI as
shown in Figure 2.