GE MicroCal iTC200, Руководство по эксплуатации

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MicroCal iTC
200
Operating Instructions 28-9639-77 AA
45
Operation 4
Instrument controls 4.7
The Pulse Control section allows for manually administering a DP calibration pulse.
While this is not the most thorough method of checking the y-axis calibration, it is the
quickest method. Pulses may be applied any time the DP signal is equilibrated and the
resulting deflection used as a crude calibration assessment. If Origin for real-time
plotting is enabled, Origin will calculate the error. If this is greater than 1%, please see
Section 5.8 for a more thorough check of the DP calibration.
The Pipette Control panel at the center of this tab provides the controls for loading and
cleaning the syringe. The Open Port button moves the plunger tip to above the fill port
in the side of the syringe. C lose Port moves the plunger tip down so that it blocks the fill
port. Purge/Refill pushes the pipette tip all the way down and back up again, dislodging
bubbles on the sides of the syringe. The Pipette Maintenance section provides the
software controls used for changing the pipette tip. Please see Section 5.5 for details on
performing this maintenance.
Insert the cell cleaning apparatus into the sample cell (see pictures below). Be sure to
push down until the device is firmly seated. Attach the syringe connector to the syringe.
Click the
Cell and Syringe Wash button in the Instrument Controls tab of the iTC200
software. The software will prompt the user to be sure the cleaning tubing is inserted.
The program will first execute the
Cell Buffer Rinse (Short) procedure.
A prompt will appear after the cell wash portion of the sequence is complete. The user
may then load the cell. Click
OK to continue and clean the syringe. The program then
executes the Syringe Wash (Short) procedure. The syringe cleaning takes about nine
minutes. Once that has completed, the syringe may be loaded with sample.
Leave the tubing connected to the syringe. Leave the syringe in the wash position or the
rest position.
Click Syringe Load .
The plunger will move to the bottom of the syringe to prepare for loading. This must be
performed with the syringe NOT in the titrant to prevent turbulence and gassing of the
sample. The software will prompt the user to move the pipette to the titrant.
Click OK to continue. The pipette tip will move, filling the syringe. After the tip reaches
the open port position, the pump will remove the air bubble, reducing titrant usage. The
port will move to the close position and the vacuum will remove any excess titrant. Once
this has completed, the software will prompt the user to disconnect the syringe tubing,
make sure the cells are filled, and move the pipette into the sample cell.
The cell cleaning device must be inserted into the sample cell until it seats firmly.
Connect the syringe tubing to the vacuum block port at the rear of the Washing Module
to prevent leakage. Click
Cell Buffer Rinse (Short) . The Washing Module will perform a
short cleaning routine, rinsing the cell with buffer.
The program will rinse the cells with buffer and then with water. It will then empty the
cell, although not all the liquid will be removed. The entire sequence takes a little over a
minute. The user may then remove the excess water and load the cell with sample,
using the Hamilton loading syringe.
The cell cleaning apparatus must be inserted into the sample cell until it seats firmly.
Connect the syringe tubing to the vacuum block port to prevent leakage. Click
Cell
Water Rinse (Long) . The Washing Module will perform a more thorough cleaning
routine, which takes about 80 seconds. Like the Cell Buffer Rinse (Short) , the program