Ensuring System Wellness (IC Devices)
Calibrating the AS Inject Port Volume

When to calibrate the inject port volume:

After replacing the needle seal assembly, or if reproducibility between injections is poor.

The inject port volume is the volume of tubing between the AS inject port and the injection valve. The autosampler uses this information to determine how much fluid to push through the line in order to position the sample correctly in the loop for precision injections.

Note:

For Sequential mode injections, the volume to be calibrated includes the needle seal line, the path through the diverter valve, and the diverter tubing to the injection valve.

Open the Inject Port Volume Calibration panel:

  1.  Open the Browser and open a panel tabset.

  2.  Select the Autosampler tab.

  3.  In the Wellness group, click the Calibrate IPTV button. The Inject Port Volume Calibration panel appears.

Follow the instructions on the panel to complete the calibration procedure. Refer to the appropriate notes below. The procedure is slightly different, depending on whether the AS is in Normal or Sequential mode.

Notes for Normal Mode:

Preparing:

After disconnecting the needle seal line from the injection valve, route the line outside the autosampler or chromatography compartment.

Step 1:

Clicking Setup empties the needle seal line. The AS then dispenses 25 mL into the inject port. This nearly fills the needle seal line (minus a few microliters).

Step 2:

After clicking +1 uL, wait until the sound of the syringe motor stops before clicking +1 uL again.

Continue clicking +1 uL, until a tiny drop of liquid appears at the end of the needle seal line. If you go too far and more than a single small drop of liquid appears, click -5 uL. The AS empties the line and then fills the line with 5 ml less than was cleared. You can then begin clicking +1 uL again.

Step 3:

After clicking Test, verify that a drop of liquid appears at the end of the needle seal line. If no drop appears, or if the size of the drop is different than previously observed, click -5 uL and repeat the procedure.

Step 4:

After clicking Done, the new calibration value is displayed on the panel. Write this value on the label inside the AS front door.

Finishing:

Reconnect the needle seal line to the injection valve. Tighten the fitting fingertight and then tighten an additional one-quarter turn using a 5/16-in wrench.

Notes for Sequential Mode

Preparing:

After disconnecting the diverter valve lines from the injection valves, route the lines outside the autosampler or chromatography compartment.

Step 1:

Select Diverter Valve Position_1 to calibrate the inject port volume for system 1.

Step 2:

Clicking Setup empties the needle seal line and the diverter line.

Step 3:

Enter an approximate volume using the following formula: ~0.8 ml/cm (~2 ml/in) for the diverter line + the volume of the needle seal line (which is written on a  label on the tubing and also inside the AS door). Then, click Estimate. The AS dispenses the volume entered, which will nearly filsl the diverter and needle seal lines (minus a few microliters).

Note:

The value ~0.8 ml/cm (~2 ml/in) used for calculating the diverter line volume assumes the tubing ID is 0.330 mm (0.130 in). For volume per length values for other tubing IDs, refer to Selecting the Syringe Speed.

Step 4:

After clicking +1 uL, wait until the sound of the syringe motor stops before clicking +1 uL again.

Continue clicking +1 uL, until a tiny drop of liquid appears at the end of the diverter line. If you go too far and more than a single small drop of liquid appears, click -5 uL. The AS empties the line and then fills the line with 5 ml less than was cleared. You can then begin clicking +1 uL again.

Step 5:

After clicking Test, verify that a drop of liquid appears at the end of the needle seal line. If no drop appears, or if the size of the drop is different than previously observed, click -5 uL and repeat the procedure.

Step 6:

After clicking Done, the new calibration value is displayed on the panel. Write this value on the label inside the AS front door.

Calibrate System 2:

Select Diverter Valve Position_2 and repeat the calibration procedure for system 2.

Finishing:

Reconnect the diverter lines to the injection valves. Tighten the fittings fingertight and then tighten an additional one-quarter turn using a 5/16-in wrench.