HP 3457A Service Manual page 202

Satisfactory completion of the self test routine is indicated by a display message of SELF TEST OK. If
an error is detected, the display message will be TEST FAILED and the front panel ERR annunciator
will flash. This indicates the ERR? register contains a nonzero value. If the ERR? command returns a
value of one (I) there is a hardware error (see ERR? command in Command Reference Section of HP
3457A Operating Manual). Another method of determining the failure mode is to read the ERROR
register (Presy the Blue SHIVT key then the ERROR key). \f there is a hardware error, examine the
AUXERR register by executing the command AUXERR?. A number will be displayed that indicates
the specific test(s) that failed.
This number corresponds to self test failure information in Table 8-2. If,
for example, the number 32 is displayed on the control panel when the AUXERR? command is ex-
ecuted, Table 8-2 shows that AUXERR 32 corresponds to a Current Source, Gain Selection, Input
Divider failure. If more than one test fails, the AUXERR numbers will be summed together. For ex-
ample; if the Front end zero measurement test and the AC attenuator flatness test failed, the AUNERR
number displayed would be 272 (256 + 16). For troubleshooting purposes, the lowest numbered
AUXERR failures should be repaired first. Left of the AUXERR#, in Table 8-2, is a TEST#. This
TEST# corresponds to the test descriptions provided in the Self Test (TEST) paragraphs in this section,
Table 8-2. Self Test Failure Information
TEST# AUXERR# FAILURE DESCRIPTION
N/A 1 Isolation error in normal operation (not during self test)
1 [ 2 A/D controller self test error
2 4 Isolation self test error
3 8 Integrator convergence error
4 16 Front end zero offset error
5 32 Current source, gain select or input divider error
ai |
6 64 Amps function error
4 128 AC amplifier DC offset error
8 256 AC attenuator flatness error
9 512 Ohms precharge circuit error
0 1024 U502 ROM checksum error
0 2048 U503 ROM checksum error
0 4096 Nonvolatile RAM (U511) failure
0 8192 Volatile RAM (U506) failure
0 16384 Calibration Ram (U511) or RAM protection circuit error
* For instruments S.N. 2538A02954 and above see Table 8-3.
HP 3457A Multimeter
8-37