4-54
Agilent 7500 ICP-MS ChemStation Operator’s Manual
Tuning
NOTE Once the parameter of the reaction gas flow rate is tuned; only a fine adjustment of
the flow rate is enough for daily tuning.
He Mode (When Helium is used as the Reaction Gas)
It is recommended to tune in He mode after tuning in H
2
mode.
Autotune cannot be used in He mode.
The following is an example of the sensitivity adjustment method in He mode: This
assumes that adjustment in H
2
mode is complete. First, tune the lens voltage with an
appropriate He flow, and then adjust the He flow for optimum conditions.
1 Adjustment of lens voltage
a.Save the tuning parameters from H
2
mode.
b.Aspirate the tuning solution and confirm that Co (59 amu), Y (89 amu), and
Tl (205 amu) show normal counts in the ICP-MS Tuning-Sensitivity
Window.
c.Turn Reaction Mode Check Box ON and set the value 3.5 mL/min. for the
He Gas flow rate.
d.Check the sensitivity. If the sensitivity is not enough, tune same as H
2
mode.