Preliminary Calibration - HP 3457A Service Manual

c. The display will show CALNUM? and the current calibration number.
& d. Press any key to return the instrument to normal operation,
5-13, PRELIMINARY CALIBRATION PROCEDURES
5-14, The following steps should be performed prior to calibration of the 3457A:
a, Select the calibration area. The 3457A may be calibrated in a "bench" environment or in a system
cabinet. For greatest accuracy, select an area where the temperature is between 18°C and 28°C and
stable within +5°C.
b. Connect the 3457A to an appropriate power source and turn the instrument ON. The 3457A can
operate on line voltages from 100 Vac to 240 Vac, 50 Hz or 60 Hz. Refer to Section II, Line Voltage
Selection, for proper rear panel switch settings and fuse selection.
c. Remove all external input signals from the front and rear/scanner input terminals.
d. Run the instrument Self Test. (Press the Blue SHIFT key then the © / TEST key). The display will show
TESTING while the test routine is running.
1. If the display shows SELF TEST OK after the test has completed, continue with step "e".
2. If the display shows TEST FAILED, check the ERROR message. (Press the Blue SHIFT key then the
- / ERROR key).
© If the Error Message reads OUT OF CALIBRATION, continue with step "e". (It is probable
ee that performing the Calibration Procedures will eliminate this error).
© If the Error Message reads HARDWARE ERR, check the AUXERR? (Auxiliary Error) mes-
sage for additional information. (Press the Blue SHIFT key then the NPLC / A configuration key. Use
the |, scroll key to display AUXERR. Press the ENT key).
O An AUXERR? message of 16 indicates the Input Amplifier Offset is beyond tolerance.
Perform the Input Amplifier Offset adjustment (Paragraph 5-15) and repeat steps "d"
through "h " of this procedure.
O An AUXERR? message of 256 indicates the AC attenuator frequency compensation is
beyond tolerance. Perform the AC Convertor Frequency Response adjustment (Paragraph
5-17) and repeat steps "d "through "h" of this procedure.
O An AUXERR? message, other than 16 or 256 indicates a component failure. Refer to
Section VIII for repair procedures.
e. Allow the instrument to warm-up for a period of one hour.
f. Run the AUTO CAL (Auto-calibration) routine. (Press the AUTO CAL configuration key, to display the
ACAL command, enter the number | and press the ENT key ).
g. Record the Calibration Number if desired. (Refer to paragraph 5-10).
h. Proceed to the calibration procedures beginning at paragraph 5-19.