Fluke 5790B - Calibration Security Passcode; Long-Term Commands

5790B
Operators Manual
6-6
Calibration Security Passcode
The integrity of the Product calibration is protected by a security passcode that
must be entered before new calibration constants can be saved to non-volatile
memory. This passcode replaces the hardware calibration switches found on the
Fluke 5790A. The calibration can be run without the passcode, but the
coefficients cannot be saved until the product is unsecured.
Note
Calibrating the Product while in a secured state results in the new
calibration constants being temporarily used until the Product is
powered off or  or the reset remote command is used. This is a
feature that can be used to temporarily improve the accuracy of a
given range without affecting last full calibration.
As with the 5790A, the passcode protects the ability to set the date for the
internal real-time clock.
Once the passcode is entered, it is unsecured. The Product can be unsecured at
any time over the remote interface with the CAL_SECURE command. The front
panel prompts for the passcode to unsecure the Product before it can accept
new values to be eventually secured. The Product secures itself when it is
powered on or using the *RST remote command.
The passcode contains 1 to 8 decimal digits. The Product is shipped with a
default passcode set to "5790". To change the passcode, touch Setup Menu >
Calibration > Change Cal Passcode. The Product prompts for the current
passcode and then the new passcode. The passcode can also be changed over
the remote interface with the CAL_PASSWD command.
Like the 5790A, the 5790B also has some calibration commands that require you
to set the calibration secure state to “SERVICE” cal mode. This requires a
separate passcode that is only available by contacting Fluke Customer Support.
You will need to know the Product serial number to acquire the SERVICE
passcode. If the passcode is lost, contact Fluke Customer Support. See How to
Contact Fluke Calibration in Chapter 1.
Long-Term Commands
Some remote commands take a relatively long time to execute. These are called
"long-term commands" and they are identified as such in the command
descriptions in this chapter. If a command that produces a change in instrument
state is received during the execution of a long-term command, for example,
CAL_AC, the command is not executed and a device-dependent error occurs.
(Bit 3 in the Event Status Register is set to 1 if enabled, and the error code for
the error is available to be read from the error queue. See the "ERR?" command
for more information.)