HACH LANGE QuikChem 8500 2 Serie Wartung Und Fehlerbehebung Seite 19

3. Disconnect the carrier tubing fitting that is attached to the carrier pump tubing adapter, which is
found between the pump tubing and the valve.
a. If the flow problem is still there when the carrier tubing is disconnected, find the clog or crimp
location before the disconnected point.
b. If the flow moves forward, there are no total clogs up to that point. Put the carrier connection
back in place. The flow problem will be back. Continue this process to find the clog or more
blockages down stream.
4. Loosen the connector at port 2 of the valve.
a. If the flow problem goes away, there are no clogs up to that point before the valve. Connect
port 2 and continue to look for the clog.
b. If the problem does not go away after port 2 is disconnected, there is a clog between the
pump tubing adapter and the valve connector.
5. Loosen the valve connector at port 3.
a. If port 3 does not have a leak, there is an internal clog in the valve or a blockage in the sample
loop.
b. If port 3 has a leak, look at each connection on the manifold with this process. To remove
clogs, clean the connectors (tees, unions, etc.) or replace the Teflon tubing.
Sometimes a dye test is necessary to find the a clog or partial clog. Refer to
on page 17.
Identify a detector fault
It is important not to connect a detector to the system unit when the power is set to on. To find out if a
detector is at fault:
1. Operate a method. It can be a dry operation.
2. While the method operates, pull the flow cell out to see if there is a response on the diagram. If
the detector does not give a result, contact technical support.
Note: If the detector is unplugged, the baseline will be located at zero.
Identify the dilutor accuracy
To make sure that the accuracy of the dilutor is correct:
1. Operate five manually-diluted and five autodiluted standards. Compare the results to find out if
the problem is the dilutor or elsewhere.
2. Operate a dye test. Use the dilutor to make a series of standards from the stock universal dye.
Use one manifold. Make sure that the concentrations entered in the sample tab agree with the
dilutions that are used.
3. Make sure that the filter wavelength is 480 to 660 nm and the sample loop is 20 to 25 cm. Make
sure that the calibration curve received is linear and the residuals are less than 1 percent.
4. If the dilutor leaks, contact technical support.
Note: Make sure that the high standard peak amplitude is less than 5 V. If it is higher, change the stock
universal dye 1:2 with deionized water. Otherwise, the calibration will not be linear. Make sure that the
wavelength of the filter used is less than 660 nm. Peaks are not detected with an 880-nm filter.
Do a dye test
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