[GC Stop Sequence] Screen

Press HOME button - [GC Start/Stop Sequence] while the GC is turned on to display [GC Stop Sequence] screen.
You can set parameters related to the GC shutdown such as stop time, flow off time, and sleep time.

No. Item Description
Stop Time Sets the period of time after [Stop GC] is pressed until the instrument stops temperature/detector control.
Range 0.0 to 6000.0 min
Default 0.0 min
Flow Control Displays the current status of flow control. Press [Off] or [On] to switch the control status. Select [On] to continue the carrier gas flow after the GC shutdown. Select [Off] to end it after the GC shutdown. Select [Off] to stop gas flow after the time set in [Flow Off Time] elapses.
Items Off, On
Default On
Flow Off Time Sets the period of time between the end of temperature/detector control and the end of gas control. This can be set when [Flow Control] is [Off].
Note

  • The system starts to count the flow off time after the temperature reaches the set value in [Makeup Gas Stop Temp] when the detector is TCD or SCD and in [ECD Gas Stop Temp] for ECD.

  • When the detector is BID, set [Flow Off Time] at a value more than 60 minutes because flow control should be stopped after helium purifier is cooled adequately. If flow control stops when helium purifier is hot, it accelerates degradation of helium purifier.
Range 0.0 to 6000.0 min
Default 0.0 min
Sleep When [Enable] is selected, the instrument will go into sleep mode automatically after the time set in [Flow Off Time] elapses. This can be set when [Flow Control] is [Off].
Items Enable, Disable
Default Disable
Restart The action when [Disable] or [Enable] is selected are different depending on the settings in [Sleep].
Sleep Restart Operations after the GC shutdown
Disable Disable None
Enable Disable The instrument goes into sleep mode.
Disable Enable The GC will automatically start after the time set in [Restart Time] elapses.
Enable Enable The instrument will go into sleep mode after the time set in [Flow Off Time] elapses. After the time set in [Restart Time] elapses, the instrument will be automatically turned on and the GC will start.
This can be set when [Flow Control] is [Off].
Items Enable, Disable
Default Disable
Restart Time Sets the time until the instrument will be automatically turned on. Count starts after control of temperature and the detector is stopped. Count starts at the same timing as flow off time. This can be set when [Restart] is set at [Enable]. When the time is set at a value lower than [Flow Off Time], the instrument restarts instead of going into sleep mode even if [Sleep] is set at [Enable].
Range 0.1 to 6000.0 min
Default 0.1 min
Stop GC When you press [Stop GC], the GC will stop according to [GC Stop Sequence] screen settings. If you press [Stop GC] while the instrument is performing analysis, GC stop is scheduled and [Abort] is displayed. Press [Abort] to cancel the GC stop. During the GC Shutdown, [GC Start Sequence] is displayed. Press [GC Start Sequence] to display [GC Start Sequence] screen.
Item Description
GC Start Sequence Displays [GC Start Sequence] screen.
File Displays [File Select] screen. You can change the file to be used.
Clean Up Displays [Clean Up] screen. You can set parameters for clean up during the GC startup.

Examples for the GC stop

The flow off time should be changed depending on the column oven temperature.
The following examples show various GC stop sequence adapted to the conditions of the instrument.

Note

To protect columns, set the time so that the carrier gas flow stops after each parts is cooled during the GC shutdown.

Note

If the carrier gas stops while the column oven temperature is high, the liquid phase of the column may be degraded. The flow off time should be set at a value where the column oven temperature drops adequately.

Note

When the GC is turned off, the oven fan automatically stops based on settings in [Fan Off Temp].