Shimadzu GC-2014 - AFC and APC Offset Calibration

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12 Injection Port
12.4
12.
GC-2014
12.4AFC and APC Offset Calibration
The pressure and flow rate sensors of AFC and APC may become slightly off after long
periods of use. If the sensor values deviate, “0.5 kPa” or “0.5 ml/min” is indicated for
pressure or flow rate instead of zero even when there is no gas flowing.
In this case, perform the offset (zero point) calibration. Calibration is especially effective
when data reproducibility is important.
Calibration procedures are as follows.
1. Set the temperatures of the injection port, column oven, and detector low and wait until
they become 40 °C or lower.
(AFC calibration is performed when there is no gas flowing. Stopping gas when parts'
temperatures are high may cause deterioration of columns.)
2. Press the [SYSTEM] key, select “Start Seq” (PF menu), and check the mode to start the
GC when the power is turned on. If it is not set to “Manual Start,” change it.
3. Turn off the power and reboot it.
Rebooting leaves the unit at the state of SYSTEM OFF.
Do not shut off gas supply by turning off the main valve or by any other measures.
Performing calibration without primary pressure makes the zero point off.
4. To perform AFC calibration, completely empty out the gas by detaching the septum of
the injection port.
To perform APC calibration, wait until when the pressure or flow rate does not fluctuate.
5. Press the toggle key on each flow controller's parameter setup screen until the “Offset”
PF menu is displayed. For AFC, press the [FLOW] key once and the toggle key twice.
6. Press “Offset” (PF menu).
The message “Zero Calibration Start” appears. Approximately 10 seconds later, the
message “Zero calibration completed” appears indicating that the calibration is
complete.
7. Return the septum of the injection port to its original position if it has been detached.
Fig. 12.4.1 (AFC) Fig. 12.4.2 (APC)