Calibration Procedures - Front Paneliiiputs: " 3 - HP 3457A Service Manual

3457A
Calibration
f. Lay the plug-in support assembly over the front panel to gain access to the AC convertor frequency
response adjustment (Gain/Flatness A3C332).
g. Reconnect power to the instrument and turn it ON.
h. Run the AC Auto-Cal routine. (Press the AUTO CAL configuration key, enter the number 2 and press the ENT
key ).
i. Enable Diagnostic Routine number 8. (Press the Blue SHIFT key then the AUTO ZERO / D configuration
key. Use the | scroll key to display DIAGNOSTIC. Enter the number 8 and press the ENT key).
j. Use an insulated adjustment tool to adjust A3-C332 (Gain/Flatness adj) until the display reads
PASSED 0.
n, Reconnect power and turn the instrument ON.
5-19. CALIBRATION PROCEDURES - FRONT PANEL INPUTS
5-20. Calibration of the 3457A from the front input terminals consists of calibrating the offset and gain of
each range for the DCV, 2-Wire Ohms, 4-Wire Ohms and DCI Functions and gain of each range for the
ACV and ACI Functions. The FREQ Function is calibrated at one frequency.
The Preliminary Calibration Procedures should be completed before attempting
the following procedures.
5-21. DC Volts Offset Calibration - Front Terminals
5-22. Equipment Required. A low thermal short (copper wire) is required for this procedure.
a. Select the DC Voltage Function. (Press the DCV function key ).
b. Connect a short between the front panel HI and LO input terminals.
range).
5-5