TELETECH TX 916, Руководство оператора

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pg. 13
However, should the technician wish to perform additional tests
following the Pair Identification process, it is recommended that the
following connections be made prior to commencing Pair
Identification:

Red test lead with:

Red clip to Exchange 'a' wire (+’ve);

Black clip to Exchange 'b' wire (-‘ve);

Blue test lead with:
o
Red clip to Exchange 'a' wire (+’ve);
o
Black clip to Customer 'b' wire (-‘ve);

Connect White lead to the cable sheath (‘e’);

Remove jumper.
Note: If the leads are not connected this way then it is possible to
short a customer's working service if the cross-connection (links,
jumper, etc.) have not been opened and the OSCILLATOR is
switched to EXCHANGE CONNECT mode. Similarly, a short
circuit can occur when the cross-connection is being restored and
the Oscillator has been left in EXCHANGE CONNECT mode.
Move to the Far End of the Line and use the PROBE tip to identify
the cable pair carrying the OSCILLATOR tone signal. Confirm the
pair by selecting a different mode and checking that the
OSCILLATOR’s tone stops. The PROBE’s sensitivity (volume)
can be adjusted by using the TONE key (refer to section 5.3
TONES).
6.2. CHECK FOR BALANCED PAIR
This is accomplished by moving the PROBE tip between the ‘a’ and
‘b’ wires of the cable pair carrying the signal and identifying a null
point (place of negligible signal volume). If no null point is found
then the cable pair is unbalanced and a cable fault is likely present
(refer to section 6.3 FAULT LOCATION).
6.3. FAULT LOCATION
A technician should refer to their fault location test instrument’s
manual for more details. In these manuals the Oscillator is often
referred to as a Remote or Far End Device (FED).
Two Wire Test
This test is performed on a pair containing one good wire and one
faulty wire with leakage to ground. The test requires the use of a
Resistance Bridge in addition to the Loop-a-Line. The test is as
follows:

At the Exchange, connect the Blue and Red
OSCILLATOR leads (refer section 6.1 PAIR
IDENTIFICATION);