5-18 682XXB/683XXB MM
Internal DVM Tests
Error 100 DVM Ground Offset Failed, or
Error 101 DVM Positive 10V Reference, or
Error 102 DVM Negative 10V Reference
Description: The DVM circuitry, located on the A16 CPU Interface
PCB, is calibrated using the ±10 volts from the reference supplies on
the A12 Analog Instruction PCB. The error messages indicate a
calibration-related problem or a defective ±10 volt reference.
Step 1. Perform a manual pre-calibration. (Refer to chapter 4 for the
calibration procedure.)
Step 2. Run self-test.
If no error message is displayed, the problem is cleared.
If any of the error messages, 100, 101, and 102, are dis-
played, go to step 3.
Step 3. Connect the negative lead of the DMM to A12TP1.
Step 4. Measure the ±10V reference voltages at A12TP4 and
A12TP8. A12TP4 should be –10V ±0.036V; A12TP8 should
be +10V ±0.036V.
If the ±10V reference voltages are correct, go to step 5.
If incorrect, replace the A12 PCB.
NOTE
Even if the ±10V reference voltages are correct, there could
still be a malfunction of the DVM multiplexer on the A12
PCB or the DVM circuitry on the A16 CPU Interface PCB.
Step 5. Replace the A12 PCB and run self-test again.
If no error message is displayed, the problem is cleared.
If any of the error messages, 100, 101, and 102, are dis
-
played, go to step 6.
Step 6. Replace the A16 PCB, then run self-test.
If no error message is displayed, the problem is cleared.
If any of the error messages, 100, 101, and 102, are dis
-
played, contact your local ANRITSU service center for
assistance.
Table 5-5. Error Messages 100, 101, and 102
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