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4.4.5When Emission Current is not Set at Normal Value
When emission current is not set at a normal value when you applied HV, check the followings.
(1)If emission current indicator is not zero but smaller than the value selected in the Set Ie to box in the HV control dialog window, check the value of Vext on the dialog window.
If it is near the maximum (6.4kV) , and it is just after you made flashing, the FE tip may be the end of its life. Contact a service engineer.
If it is long after flashing, carry out flashing again.
(2)If emission current reading is zero and a
CAUTION
Beware of
electric shock
•Voltages up to 100 V AC and 30 kV DC are used in this instrument. Touching the interior could cause an electric shock.
•Never remove the covers of main unit, control unit or power unit and touch internal parts or circuits while power is connected to the instrument. There is a danger of fatal or serious injury due to electric shock.
•Do not detach the covers of the instrument.
4.4.6When Image is not Shown on Screen
If you do not observe image on the image screen or difficult to focus the image, check the followings.
(1)Check if a specimen is set normally, HV is on and emission current is about normal value, the gun valve is open, SE signal is selected, 1st condenser lens is set at 5, magnification is set at lowest and scan is running.
(2)Set contrast at maximum.
(3)Open the Alignment dialog window and start Beam Alignment mode. If a circular image appears at out of the center of screen, carry out column alignment.
(4)Open the Alignment dialog window and start Beam Alignment mode. Set the beam monitor and the objective lens aperture at 0. If a circular image appears, carry out column alignment.
(5)If you can not fix the trouble by checking above, contact a service engineer.