MKS Spectra 138A, Инструкция по эксплуатации

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PAS Trolley Manual
LP101017 Rev 1.02
Page 23
RGA is operating at its optimum pressure and that all interlocks are
satisfied.
For process pressures between 1x10
-3
and 10 mbar, the high
conductance valve should be closed and the needle isolation valve
opened which allows the needle valve itself to be adjusted to attain
the required operating pressure as described above.
Note that the needle isolation valve should be opened during
pumpdown to allow the interspace between the valve and the needle
valve to be evacuated.
4.9. Operation with remote mounted analyser
To minimise pump down times of the connecting bellows, and to
minimise water contamination in the bellows, the analyser assembly
can be used remotely from the base unit (cart). This mode of
operation also minimises any low background noise sometimes
associated with close coupled diaphragm pumps.
Ensure that the instrument has been shut down and the mains power
removed from the system. In addition it is recommended to check
that the turbo pump has stopped. This can take up to 5 minutes after
the system has been switched off.
To remove the analyser assembly from the base unit, loosen the
securing hand wheel and lift the assembly clear of the cart. Care
should be taken to avoid damaging any cables or connectors on the
analyser assembly when the assembly is removed and that the
umbilical cord is neatly coiled when re-assembling.