Agilent Technologies 9191610, User Manual

Page: 52 / 98

4 Installation Procedure
Operating Procedure
52/98 VacIon Plus 300 pumps User Manual / 87-900-103-01 (H)
Operating Procedure
Check that the controller HV polarity is correct for the pump:
positive polarity for Diode pumps and negative for StarCell or Triode
pumps. Refer to the relevant pump control unit instruction manual
and follow the procedure below when operating the pump:
1
With a clean roughing pump, establish a minimum starting
pressure in the vacuum system per the table on page 9 for the
type of ion pump.
2
Plug the control unit into a suitable power source and switch the
power ON.
3
Observe the voltage, current, and roughing pressure. If started at
5x10
-2
Torr (mbar), a controller voltage of approximately 300 to
400 volts is typical. A current value near the short-circuit current
of the control unit could indicate that an unconfined flow
discharge exists in the pump and system. A temporary rise in
roughing pressure will usually be noticed during any starting
procedure.
4
Allow the roughing valve to remain open after turning on the ion
pump until an adequate starting pressure is reached. If the ion
pump voltage drops after closing the roughing valves, reopen the
valve for additional rough pumping. As the pressure decreases,
the voltage again will rise, and the roughing valve may be closed.
5
When the voltage has increased to 2-3 kV, place the control unit
in the PROTECT condition. The system is now automatically
protected against pressure increases to 10
-4
Torr (mbar) when the
pump is left unattended. If such an increase should occur, the
control unit will be turned off automatically.
6
The pressure in the pump can also be determined by reading the
current and converting this reading to pressure with the
appropriate pressure versus current graph shown in the
appendix “Technical Information” of this manual.