34
HC Adjustment
Follow these steps to adjust the system to the chosen operating conditions.
1. Adjust the beam current.
a. Select the beam voltage (refer to Step
10. on page 33
).
b. Adjust the discharge current to obtain the chosen beam current
(refer to Step
5. on page 31
).
Do not select beam current while in Manual mode.
2. Adjust for a minimum accelerator current.
a. Adjust the accelerator voltage to minimize the accelerator current
(refer to Step
12. on page 33
). Typically, the accelerator current
should be no more than 10% of the beam current.
•
Excessive accelerator currents may be an indication of mis-
aligned grids or a system pressure above 4 x 10
-2
Pa (3 x 10
-4
Torr).
•
Refer to the ion source technical manual for grid alignment
procedures.
b. Adjust the operating conditions and/or gas flow rate to bring the
A/B Ratio within the recommended limits.
When the accelerator-current-to-beam-current ratio exceeds the pro-
grammed A/B Ratio value, an audio alarm will sound, if enabled, and an
E25 error message will appear on the Accelerator Current display.
Operating the ion source with high accelerator current may damage the
grids.
3. Adjust the hollow cathode neutralizer emission current until the emis-
sion current is about 100% to 125% of the beam current (refer to Step
8. on page 32
).
•
When the neutralizer current is satisfactory, the MPS-3000 CE
HC should be completely adjusted for Manual mode opera-
tion.
•
The user may continue operating in Manual mode or may
select Local mode (refer to
“Local Operation” on page 42
).
HC Storing Operating Conditions
All adjustable operating conditions are stored automatically in the selected
memory location when the Adjust knob is turned. This is the only method of
storing parameters.
NOTE
NOTE
CAUTION
Summary of Contents for MPS-3000 CE
Page 1: ...MPS 3000 CE Power Supply Technical Manual 425964...
Page 2: ...MPS 3000 CE Power Supply Technical Manual...
Page 90: ...86 Filament Cathode with Filament Neutralizer or PBN Option...
Page 91: ...87 Hollow Cathode and HCN 7 pin or 2 x 4 pin feedthrough...
Page 92: ...88 Hollow Cathode and Hollow Cathode Neut 6 pin feedthrough...
Page 93: ...89 Filament Cathode with Filament Neutralizer or PBN Option...
Page 94: ...90 3cm Source Filament Cathode and Filament Neutralizer...
Page 95: ...91 3cm Source Hollow Cathode and Hollow Cathode Neutralizer...
