Technical Information
Functions
Step-mode / Fixed mode
The high voltage provided to an Ion pump can change from 3kV up to 7kV.
The user can set the Fixed mode with the voltage of 3kV or 5kV or 7kV using the
front panel or through the serial commands or through the remote I/O.
In order to optimize the pumping speed of the Ion pump and to minimize the
influence of the leakage current, the controller implements the Step-mode function.
With this function the controller provides 7kV for about 5 seconds, then it changes
the voltage among 3 – 5 – 7 kV depending on the current drawn by the ion pump
and on the ion pump type.
To change from step to fixed voltage and viceversa: while pressing the key
FIXED/STEP, press the HV-x, where x corresponds to the HV channel, and
select 3 – 5 – 7 KV.
When the STEP I active, a square is visible on the display, corresponding to
the relative HV channel.
Table 3
Pump
Type
1000 Diode
500 diode
300 diode
150 diode
75-55-40 diode
20 diode
10 diode
1000 Starcell
800 StarCel
500 StarCell
300 StarCell
150 StarCell
75-55-40 StarCell
20 StarCell
Agilent 4UHV Ion Pump Controller User Manual
Current for switching
from 7kV to 5kV
7.3E-4
1.4E-3 A
7.2E-4 A
3.6E-4 A
2.2E-4 A
2.0E-4 A
2.0E-5 A
3.6E-3A
2.0E-3A
9.0E-4 A
5.5E-4 A
3.0E-4 A
1.3E-4 A
6.5E-5 A
Current for switching
from 5kV to 3kV
2.0E-5A
3.9E-5 A
2.1E-5 A
9.5E-6 A
6.7E-6 A
2.7E-6 A
6.0E-6 A
9.8E-5A
5.0E-5A
2.5E-5 A
1.6E-5 A
8.5E-6 A
3.8E-6 A
1.9E-6 A
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