Thermo Scientific 48iQTL, Instruction Manual

Page: 149 / 280

Calibration
Calibration
Thermo Scientific 48iQTL Instruction Manual 4-7
Use the following procedure to calibrate points 1, 2, and 3:
1. Adjust the zero air flow and the CO flow from the standard CO
cylinder to provide a diluted CO concentration of approximately 80%
of the upper range limit (URL) of the instrument. The total air flow
must exceed the total demand of the analyzer connected to the output
manifold to ensure that no ambient air is pulled into the manifold vent.
The exact CO concentration is calculated from:
)
F
+
F
(
)
F
x
]
[CO (
= ] [CO
CO D
CO
STD
OUT
Where:
[CO]
OUT
= diluted CO concentration at the output manifold, ppm
[CO]
STD
= concentration of the undiluted CO standard, ppm
F
CO
= flow rate of CO standard corrected to 25 °C and 760 mmHg, L/min
F
D
= flow rate of dilution air corrected to 25 °C and 760 mmHg, L/min
2. Allow the instrument to sample the CO concentration until a stable
response is obtained.
3. From the Home Screen press Calibration>Advanced
Calibration>Multipoint Calibration>
Point 1 .
4. Enter the span concentration being introduced to the instrument. Press
Calibrate .
The instrument will perform a series of calculations and save the new
parameters.