REI TALAN 3.0, Руководство пользователя

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MANUAL TEST FUNCTIONS
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A wire must be available for the associated wire or pair to be tested, even if the pair is defined
as a balanced pair.
It should be noted that capacitance measurements may vary greatly because capacitive
coupling varies greatly between unbalanced pairs. However, balanced pairs should have very
consistent capacitance measurements.
The example below shows a Samsung digital phone system that uses a 45-volt supply on the
main pair of 4:5. In this example, the balanced pairs are 1:2, 3:6, 4:5 and 7:8.
The balanced pairs should have the same capacitance values (2.97nF in this example) as
indicated for pairs 1:2, 3:6, and 7:8. The capacitance value of 4:5 is not measured because the
pair is active with voltage on the line.
There may be situations where signal conditions are such that a given test does not remain on
the pairs or wire long enough to be able to give a reliable reading. For these instances, the user
can change the
Dwell time selection from Default to Extended .
The
Dwell selection is available in the Manual DMM and Audio tests, as well as the Sequence
DMM and Audio tests.
While the Dwell selection is remembered and used when going between different test types
and test screens, it is NOT retained when the TALAN is powered off then back on.