BASIC OPERATIONS
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1. Response level in pair 4-5 is significantly higher, than on other pairs.
2. In pair 4-5, the distance to the heterogeneity is less than the cable length.
CONCLUSION:
the reference structure is broken. The probable cause of structural disruption is
a defect in pair 4-5 (parallel connection at a distance of ≈10 m from the beginning of the cable).
Preparation of cable for testing
All electronic devices must be disconnected from the cable. If the cable has branches, it is
necessary to test each cable segment separately, having previously disconnected it from the main
cable.
When using REF it is assumed that the cable segment under test or the cable as a whole does
not have heterogeneities. It is recommended to use idle mode (a pair of wires is open at the
opposite end).
Testing in AUTOMATED mode
Testing of a multi-wire cable begins with test in the AUTOMATED mode. The test consists in
comparing the obtained structure with the reference structure of the cable of the corresponding
type.
The purpose of the test
is to identify abnormal structural changes and identify the type of
defect detected.
Testing in MANUAL mode
Testing in MANUAL mode is performed when testing a two-wire cable or after testing in
AUTOMATED mode of a multi-wire cable.
The purpose of testing
is to localize the heterogeneity in the tested pair. MANUAL mode
testing is to compare the test results of one pair of wires from different ends of the cable.
7.4.2. TESTING OF THE MULTI-WIRE CABLE
1.
Test cable in AUTOMATED mode. Determine the structure (response levels in different
pairs and distances to heterogeneity with maximum response levels).
2.
Compare the resulting structure with the reference structure of this type of cable.
3.
If there are no differences in structures, test is end.
4.
If there are anomalies in the resulting structure, find a pair or wire with a defect. Try to
identify a defect.
5.
In MANUAL mode, test a defective pair (or pairs with a defective wire) by connecting
alternately from both sides of the cable.
6.
Analyze the results received in the MANUAL mode and specify distance to heterogeneity.
7.
By means of a cable locator, a usual NLJD and the other equipment for search to localize
the place of connection to the cable of the eavesdropping device.
7.4.3. TESTING OF THE TWO-WIRE CABLE (PAIR OF THE MULTI-WIRE CABLE)
IN MANUAL MODE
1.
Connect the Analyzer to one of the ends of the tested cable.
2.
In the MANUAL mode to take measurements in the SET 1 table.
