Metrohm 884 Professional VA, Руководство - Краткие инструкции

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5 Operation and maintenance
884 Professional VA
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5.2 Performing a Dummy cell test
Should you note any problems or irregularities during or after determina-
tions (e.g. noisy curves), you can perform a dummy cell test. In this test,
the hardware and the electrode cables up to the measuring head are
checked; this allows potential problems to be localized or excluded. The
electrodes are not tested with the
Dummy cell test .
Proceed as follows:
1 Load the Dummy cell test method template in viva .
2 Plug the three electrode cables onto the contacts of the dummy cell
(6.2813.050).
Observe the correct assignment of the electrode cables (WE, RE and
AE).
3 Place the measuring head cover and the stopper (7- 5 ) onto the
measuring head.
4 Start the determination; at the prompt, select the name of the 884
Professional VA being used from the list and wait until the measure-
ment is completed.
If the curve meets the following conditions, then defects in the hard-
ware or the electrode cables can be ruled out:
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The curve must be linear.
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At –2.0 V, the current should be –1.67 mA ± 0.33 mA.
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At +2.0 V, the current should be +1.67 mA ± 0.33 mA.