Agilent Technologies 7500 ICP-MS Operator's Manual page 149

Agilent 7500 ICP-MS ChemStation Operator's Manual
Tuning
i. If the sensitivity is low, change the Omega Bias-cs and the Cell Exit to a
lower voltage. In this case, sometimes, the background may increase.
Monitor the background when adjusting.
Typical values of Tuning Parameters in the H
(with ShieldTorch, Micro Flow Nebulizer, self-aspiration)
Parameter
RF Power (W)
Sampling Depth (mm)
Carrier Gas (L/min)
Makeup Gas (L/min)
PeriPump 1 (rps)
ºC
S/C temp ( )
Extract 1 (V)
Extract 2 (V)
-cs
Omega Bias (V)
-cs
Omega Lens (V)
Cell Entrance (V)
QP Focus (V)
Cell Exit (V)
OctP RF (V)
OctPBias (V)
QP Bias (V)
H Gas (ml/min)
2
Typical values of Sensitivity (H
Mass
Integration time = 0.1 sec.
59
Co
89
Y
205
Tl
Mode
2
Typical Value
1500
8
0.8
0.45
0.1
2
5.4
-100
-40
8.6
-30
-12
-40
180
-18
-3
4.5
Mode)
2
Count/1 ppb
> 1500
>8000
>7000
Adjustment
Normally used 1500
7 to 10
0.6 to 1.0
0.3 to 0.7
ºC
Normally used at 2
4 to 8
-150 to -60
-50 to -30
5 to 10
-50 to -30
-20 to 0
-80 to -20
100 to 200
Normally used -18
-Normally used -16
3 to 6
RSD
< 15%
< 15%
< 15%
4-73