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Keysight U1251B/U1252B User’s and Service Guide
6
Performance Tests and Calibration
To unsecure the instrument without the security code
To unsecure the instrument without the correct security
code, follow the steps below.
1
Record the last 4 digits of the multimeter’s serial number.
2
Turn the rotary switch to
.
3
Press
and
simultaneously to enter the
Calibration Security Code entry mode.
The primary display shows 5555 and the secondary
display shows SECUr.
4
Press
for more than 1 second to enter the Set
Default Security Code mode. The secondary display shows
SEr.no and the primary display shows 5555.
5
Use the editing keys
and
to step each
character in the code.
6
Use
and
to select each character.
7
Set the code, same as the last 4 digits of the instrument’s
serial number.
8
Press
(Save) to confirm the entry.
9
If the 4 digits entered are correct, the secondary display
will show PASS.
Now you can use 1234 as the security code. If you want to
enter a new security code, see
“To change the instrument
calibration security code from the front panel” on page 137
.
Make sure you record the new security code.
N O T E
If you do not have a record of the security code, you can try 1234 (the fac-
tory default code) using the front panel.