Thermo Scientific 43i, Инструкция по эксплуатации

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Calibration
Permeation Tube System
4-4 Model 43i Trace Level-Enhanced Instruction Manual Thermo Fisher Scientific
A permeation tube system, shown in Figure 4–2 can be constructed. All
connections between components in the system should be made with glass,
Teflon®, or other non-reactive material.
The air flow controllers should be capable of maintaining a constant air
flow within ±2% of the required flow rate. Ensure all devices are properly
calibrated and that all flows are corrected to 25
°
C and 1 atm.
Figure 4–2. Permeation Tube System
The SO
2
output level is calculated from:
F
K x P
=
]
SO
[
T
OUT
2
Where:
[SO
2
]
OUT
= SO
2
output concentration in ppm
P = permeation rate in μg/min
F
T
= total flow rate of gas after mixing chamber (F
P
+ F
D
) in liters/minute
K (SO
2
) = 0.382 constant for SO
2
permeant
Commercial permeation systems, such as the Thermo Scientific Model 146
Multigas Calibration System, are available for this requirement. Refer to
the instrument instruction manual for more information.
Commercial
Permeation Systems