Agilent HP 5890 GC: ApplicationCommands and Tips for Third Party Devices
Agilent HP 5890 GC: Application
Entering a Temperature Gradient
You can enter a temperature gradient either directly, using the Flow command on the Control menu (GC tab page) or by a PGM File.
Under Chromeleon, a temperature profile is possible with a maximum of three ascents or descents. (The HP 5890 GC cannot store more steps.) The maximum temperature change (ascent) is 70°C per minute.
When entering a temperature gradient in the Program, the "base point philosophy" is used (similar to entering a flow or percent gradient in HPLC). Each Temperature command is a base point for the gradient program. Understandably, no gradient is executed before the Inject command. Temperature gradients can only begin after the Inject command. If the program does not contain an Inject command, this does not apply.
Temperature Settings
Use the following commands to enable or disable temperature control of the injector, oven, and detector:
|
0.00 |
InjectorA.TempCtrl = On |
or = Off |
|
0.00 |
InjectorB.TempCtrl = On |
or = Off |
|
0.00 |
GC.TempCtrl = On |
or = Off |
|
0.00 |
DetectorA.TempCtrl = On |
or = Off |
|
0.00 |
DetectorB.TempCtrl = On |
or = Off |
To set the temperature of the single modules, for example, to 80°C, you have to use the following commands:
|
0.00 |
InjectorA.Temperature = 80 |
|
|
0.00 |
InjectorB.Temperature = 80 |
|
|
0.00 |
GC.Temperature = 80 |
|
|
0.00 |
DetectorA.Temperature = 80 |
|
|
0.00 |
DetectorB.Temperature = 80 |
|
The temperature of the injector system and the detector should always be approximately 15 - 20°C (59 - 68°F) above the current oven temperature. Reaching the nominal temperature on the instrument can take some time. Please note that the oven heats faster than the injector and the detector system. As soon as the temperature is reached, the GC sends a Ready signal. An injection via the autosampler is possible only after this signal.
Example:
The following program waits until the nominal temperature of 150°C is reached, before the Inject command is executed:
0.000 GC.Temperature = 150
Wait GC.Ready
Inject
...... ..............
Tip:
After Chromeleon has communicated the nominal temperature value to the instrument, the instrument implements the desired value as fast as possible. If the value is "almost" reached, the Equilibration Time passes until the instrument sends the confirmation message to Chromeleon. You can specify the duration of this time interval using the Equilibration Time parameter in Chromeleon.
For general information and installation instructions for the 5890 GC; refer to Hardware Installation:
Agilent HP5890 GC: Installation