Low Mass Cut-Off; Conditioning The Detector - Waters GCT Premier Operator's Manual

Low Mass Cut-Off

The low mass cut-off prevents low masses from reaching the detector by
cutting off the beam at a set time before the push.
This saves the detector from becoming saturated with data or burning out,
which can occur if exposed to high signal intensities of background ions that
are not ions of regularly required, such as air, water, CI gas, or helium.
Low Mass Cut-Off parameters:
Parameter
Set Low Mass
Cut-Off
Cut off below mass
Zero transmission
below
Data will be invalid
above

Conditioning the detector

Click Settings > Detector Conditioning to open the Detector Conditioning
dialog box, which is used to condition the detector.
B-16 The MassLynx Tune window
Description
Select the check box to enable low mass cut-off. When
selected, the cut off below mass field is enabled.
Sets a cut off mass, below which masses and
attenuated.
The value where low mass cut-off starts, which
prevents low mass ions being counted as they are
completely attenuated below this mass.
The mass above which data are not valid. High
masses are reduced in intensity and therefore the
accurate mass of the data is adversely affected. This
value can be increased using the Pusher Interval on
the Engineer tab in the Tune window.