Calibration; Introduction; Calibration Secu; Security Code - HP 3457A Service Manual

SECTION V
CALIBRATION
The information contained in this section is intended for the use of service trained
personnel who understand electronic circuitry and are aware of the hazards invol-
ved. Do not attempt to perform any of the procedures outlined in this section unless
you are qualified to do so.
5-1. INTRODUCTION
5-2, Section V contains Manual Calibration Procedures for the HP 3457A Multimeter. Section V also con-
tains information explaining the Calibration Security features built into the 3457A. The 3457A has only
two screwdriver adjustments which, under normal conditions, do not require adjusting. All calibration is ac-
complished from the front panel or through computer control.
5-3. An Automatic Calibration procedure, which includes software and instructions, is available by ordering
HP Part Number 03457-10085 (for use with the HP Model 85B) or 03457-10200 (for use with the
HP Series 200 computer), The equipment listed below is preferred for use with the Automatic Calibration
Procedure, however, other equipment may be used.
Controller - - - - --------------- HP Model 85B Computer or HP Series 200 Computer
Frequency Counter - - - --------+----++-- rrr rrr ree HP 5314A or HP 3457A
DC Voltage/Current Resistance Calibrator Datron 4000A
AC Voltage/Current/Frequency Calibrator - Datron 4200
5-4. CALIBRATION SECURITY
5-5. The Calibration Security feature of the 3457A allows the person responsible for calibration of the unit
to enter a Security Code to prevent accidental or unauthorized calibration.
5-6. Security Code
5-7. The Security Code is a six digit integer number from 0 through 999,999 (if the number entered is not an
integer number, it will be rounded to an integer value and then used). The instrument is shipped from the
factory with the Security Code set to 3457. Setting the code to zero disables the security feature.
5-8. Changing the Security Code (SECURE <old security code> , <new security code>). The procedure for
changing the Security Code is as follows:
a. Access the SECURE command. (Press the Blue SHIFT key, then the RECALL / S configuration key. Use the
| scroll key to display the SECURE command).
b. Enter the old Security Code, the delimiter ( , ) and the new Security Code. (The instrument is shipped
from the factory with the security code set to 3457). Example: To change the Security Code from 3457 to
7543, enter 3457 , 7543.
c. Press the ENT key. The instrument will now respond to the new Security Code.
5-1