Hach QuikChem 8500 2 Series, Операции

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Table 1 Port connections
Port connection Description
Sample tubing The sample moves from the sampler or the sample probe to port 6 on the injection valve.
Sample loop There is tubing between ports 1 and 4. The sample loop finds the volume of sample to be put
on the manifold for analysis.
Carrier tubing The carrier is an artificial blank solution that will move the sample on the manifold. The carrier
tubing input is always connected to port 2. The carrier solution and the carrier tubing to be
used for an analysis are specified in the QuikChem method.
Manifold The carrier stream exits the valve at port 3 and flows to the manifold.
Waste tubing When only one channel operates, the waste tubing is connected to port 5 on the injection
valve. When two or more channels operate simultaneously, port 5 of the first injection valve is
connected to port 6 of the second injection valve. Port 5 of the second injection valve is
connected to waste or to the next valve in the series. The connection between ports 5 and
6 have 15 cm Teflon
®
tubing 0.8 mm ID.
Inject position
At the inject position, the carrier flows through the sample loop to the manifold. When the valve
moves to the load position, some of the carrier is caught in the sample loop. The carrier that is
caught in the sample loop at the inject position is moved out to waste by the sample stream. The
sample stream moves through the sample loop and goes to waste.
When the valve is back in the inject position, the carrier stream flows to port 2, then to port 1 and
through the sample loop. The carrier moves the sample out through port 3 and to the manifold. The
sample stream goes in port 6 and out of port 5 to waste. Refer to
Figure 9 .
Figure 9 Inject position
1 Waste tubing/next valve 4 Carrier line in
2 Sample in from sampler or adjacent valve 5 Flow to manifold
3 Sample loop
Load position
At the load position, the sample loop is filled with sample. When the valve moves back to the inject
position, the sample that flows through the sample loop is caught momentarily.
The sample volume can be calculated from the length and the inner diameter of the tubing used. The
sample is moved on the manifold by carrier for reaction and analysis. Refer to
Figure 10 .
English 9