User guide

Options 3

Advanced User Guide 63

Measure the actual flow rate through the column using a

bubble meter. Record the value. Reinstall the column.

5 Press [Options], scroll to Calibration and press [Enter].

6 From the calibration list, select the column and press [Enter].

The GC displays the current calibration mode for the

column.

7 To recalibrate or to change calibration mode, press

[Mode/Type] to see the column calibration mode menu.

8 Scroll to Length or Diameter and press [Enter]. The following

choices appear:

• Mode

• Measured flow

• Unretained peak

• Calculated length or Calculated diameter

• Not calibrated

9 Scroll to Measured flow and enter the corrected column flow

rate (in mL• min) from the run performed above.

10 When you press [Enter], the GC will estimate the column

length or diameter based on the elution time input and will

now use that data for all calculations.

To estimate the actual column length and diameter

1 Set oven ramp 1 to 0.00, then verify that the column is

defined.

2 Perform a run using an unretained compound and record

the elution time.

3 Set the oven, inlet, and detectors temperatures to 35 °C and

allow them to cool to room temperature.

4 Remove the column from the detector.

CAUTION

When you measure the column flow rate, be sure to convert the

measurement to normal temperature and pressure if your

measurement device does not report data at NTP. If you enter

uncorrected data, the calibration will be wrong.