The following table describes the parameters that appear in the Scan Properties pane when the instrument is configured with a FAIMS Pro Duo system.

Parameter

Description

FAIMS Voltages

Select one of the following options:

  • Off: The voltages on the FAIMS Pro Duo system are turned off but experiment methods can still run.
  • Defined CVs (default): If selected, a user can define custom CV values.
  • Scanning: If selected, the method will execute as follows:
    • Automatically start and stop the CV scanning based on the value that you specify in the FAIMS CV Range (V) parameter.
    • Automatically step through the CV values that you specify in the FAIMS CV Step (V) parameter.

FAIMS CVs (V)

Available when the FAIMS voltages is set to the Defined CVs option.

Scan acquisition is repeated at each of the preset FAIMS CV values. For experiments that include both a master scan (for example, a full scan) and ddMS2 scans, the scan acquisition proceeds as follows:

  • At each preset FAIMS CV value, a master scan is acquired.
  • At each preset FAIMS CV value, the precursor ions of each master scan are subjected to ddMS2 scans.
  • NOTE: Using four or more FAIMS CV values for the scan acquisition of such an experiment results in poor performance.

Specify custom compensation voltage (CV) values. You can define 1 to 10 values. When multiple CVs are used, the cycle time is automatically divided by the number of CVs used. For example, when the cycle time is 3 seconds and 3 CVs are used, the cycle time will be 1 second for each CV.

NOTE: If multiple overlapping experiments are present in a method, only one FAIMS CV may be set per experiment.

Range: -300 to 300; Default: -45,-60

FAIMS CV Range (V)

(Available when FAIMS Voltages is set to the Scanning option.)

Specify the start and stop range values in volts for FAIMS CV scanning mode in the method. Most compounds transmit between -100 to 100 volts.

Range: -300 to 300; Default: -70–40

FAIMS CV Step (V)

(Available when FAIMS Voltages is set to the Scanning option.)

Specify the step value in volts for FAIMS CV scanning mode in the method.

Range: 1–20; Default: 5

Number of FAIMS CV Values

(Available when FAIMS Voltages is set to the Scanning option.)

This is a read–only parameter and the values are greyed out. The values are calculated from the settings associated with the values of the FAIMS CV Range (V) and FAIMS CV Step (V).