Veeco MPS-3000 CE, Technical Manual

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b. Select Limit with the FUNCTION switch. The word LIMIT appears
above the switch.
c. Adjust the keeper voltage limit up or down as needed. The value
appears on the Hollow Cathode Neutralizer Keeper Voltage dis-
play.
d. The final selected value is stored automatically in the memory, as
indicated above the MEMORY switch.
8. Select the hollow cathode neutralizer emission current.
Emission current may be selected before the internal HCN starts, but no
current will be provided by the Hollow Cathode Neutralizer power sup-
ply until the internal HCN starts and the keeper voltage is below the
keeper voltage limit.
a. Select the Hollow Cathode Neutralizer power supply with the
MODULE switch and Current with the FUNCTION switch. The
words HCN and CURRENT appear above the appropriate switches.
b. Enter the chosen value by turning the Adjust knob. The value
appears on the Hollow Cathode Neutralizer Emission Current dis-
play.
c. As the Adjust knob is turned, the emission current is entered auto-
matically into the selected memory location.
9. Apply power to the source.
To avoid electrical shock, keep clear of “live” circuits.
a. Press the SOURCE ON/OFF switch. The word SOURCE appears
above the switch. When the SOURCE switch is activated, several
changes may be observed on the front panel:
•
The hollow cathode heater current will ramp to 7.25A.
• The hollow cathode neutralizer heater current will ramp to
7.25A. Select HCN with the MODULE switch and HEATER with
the FUNCTION switch to view the heater current.
• When the source discharge starts, the discharge current will
increase to the programmed value, and the discharge voltage
will decrease.
• When the internal hollow cathode starts, the keeper voltage
will drop below 25V, and the heater current will decrease to
3.75A.
• When the internal hollow cathode neutralizer starts, the keeper
voltage will drop below 25V, and the heater current will
decrease to 3.75A.
• The emission current will increase to the programmed value
after the keeper voltage drops below the keeper voltage limit.
WARNING