Zeiss EVO - Switching Off the Microscope System

5 First Operating Steps | 5.8 Switching Off the Microscope System ZEISS
5.8 Switching Off the Microscope System
5.8.1 Finishing the Work Session | LaB₆ Filament
To obtain the maximum lifetime of a LaB₆ emitter, switch off the EHT when the microscope is not
in use and switch the gun to STANDBY mode when the microscope is not used for longer peri-
ods of time. In STANDBY mode, the filament continues to be heated, and the vacuum in the
electron column and in the specimen chamber are maintained. It is recommended that you do not
turn off the gun during its service lifetime.
The STANDBY mode is also the recommended mode to store the microscope. In this case, acti-
vate the Partial Vent on Standby checkbox in the Vacuum tab of the SEM Controls panel. This
can help to prevent oil vapors from penetrating into the specimen chamber during the period of
storage.
To further extend the service life time, you can activate the Long Fil. Life checkbox in the Gun
tab of the SEM Controls panel. This reduces the filament current to “first peak” conditions,
which provides satisfactory operating conditions for general microscopy. If optimum performance
is required, the Long Fil. Life checkbox should be deactivated.
Prerequisite
ü
The microscope is in ON mode.
Procedure
1. Click the All: button in the status bar.
2. Select EHT Off from the pop-up menu.
3. Only when interrupting work for longer periods between 2 and 7 days: In the Vacuum tab
activate the Partial Vent on Standby checkbox.
à This maintains the gun vacuum, and switches off and protects the turbo pump.
4. Exit the SmartSEM user interface. Refer to Closing the SmartSEM User Interface [
} 109].
5. Close all programs and software.
6. Select Windows start button > Power icon > Shut down.
7. At the front of the plinth, press the Standby button.
à
The microscope switches to Standby mode.
5.8.2 Finishing the Work Session | Tungsten Filament
Info
If you operate the microscope with a tungsten filament, then the EHT and the gun are always
switched on or switched off together. You cannot separately switch on or off the EHT or the
gun.
Info
The tungsten filaments have only a limited lifetime of 100–300 operating hours. If you operate
the microscope with a tungsten filament, then do the following:
4 If the microscope is not in operation, then always switch off the EHT and gun to preserve
the filament.
Prerequisite
ü
The microscope is in ON mode.
108 Instruction Manual ZEISS EVO | en-US | Rev. 10 | 354706-0780-006