Yokogawa GC8000 Process Gas Chromatograph - Manual (Page 179)

<3. Basic Operation and Startup>
3-28
IM 11B08A01-01E
(1) Type of calibration method
For a method of calculating concentration from the area or height obtained in the chromatogram,
see the Appendix E Mechanism of Calculation. A method of calculating concentration differs
depending on the Process specifi cation in the Individual peak setting.
When the Process specifi cation is the External third (external standard), conduct calibration with
the standard sample. The following are the equation of concentration by External third:
C = RK (α Si / Sb) (A (αSi / Sb) 2 + B (αSi / Sb) + 1)
C: concentration
α: calibration factor
Sb: reference area or height
Si: measured area or height
R: measuring range
K: factor
A: factor
B: factor
If the area or height is confi rmed to be proportional to the concentration, the following equation
applies:
K=1, A=0, and B=0
C = RαSi / Sb
If the user want to calculate concentration and enter the calibration value by yourself, fi rst obtain
the calibration factor or the reference area (height) by using the area (height) measured with the
standard sample and the above equation, and then enter the value in the Individual peak setting
of the calibration stream (Figure 3.23). For more information about the entering method, see the
Individual peak specifi cation by EtherLCD.
11/03/22
15:15:45
Peak Setup-Specifi c (1/5)
Stream #1 Peak #1
Using/Assigned peak num 1/10
> - Process (Type) Peak
- Process (Detail) External 3rd
- Name PK1-1
- Execution Excuted
- Synchronize to #00 #000
- Output fl ag Provided (31001)
- Range number **
- Auto gain value 0
Menu Copy1 Copy2 Atm Strm# Peak#
F1 F2 F3 F4 F5 F6
Figure 3.23 Example of calibration peak setting screen
GC8000 has two automatic calibration methods. Both automatically change the Reference area
or the Calibration factor based on a set value in the Calibration factor range in the Common peak
setting (Figure 3.24).
2nd Edition : May 11, 2012-00