First, verify that the Active Head has the same cal date stored internally as that on the sticker/cert. To verify this connect the head then press MODE - Config - Head Config. The displayed information will show the cal date.
If it doesn't match what the sticker says, change the date in the 9500 or 9500B Mainframe to match the information on the sticker.
1) Put the 9500 or 9500B in Cal mode:
The calibration switch is on the back of the 9500 or 9500B (most likely under a calibration sticker). This switch must be enabled to allow you access to the calibration mode. (This is also discussed in section 2.7 of the 9500B Manual.)
2) Enter the Cal Password
To enter the default password enter this: 2->3->5->7 (-> is the arrow symbol on the 9500 keypad) then press the “enter” key on the keyboard.
Note: if the default calibration password has been changed, and you do not know it, the unit will need to be returned to a Fluke Authorized Service Center for resetting.
3) to apply the changes
Press MODE - Config - DATE TIME (use numbers and the "square key" + E to generate the "/" between numbers)
Press the "enter" key.
To store changes press Mode - Calib - Head cal - Store head cal - STORE (no need to adjust anything or change anything else).