Rev. 11/10/00
42
Trouble Shooting Inside Wiring
Except for wire length considerations, Inside Wire Trouble Shooting is the
same as Outside Plant. Because Inside Wire lengths are much shorter, various test
values will differ significantly. Successful Fault Analysis is dependent upon the
following tests and meter readings.
Testing for Good Ground
1.
Connect the Green lead to Ground.
2.
Connect the Tip (black) or Ring (red) lead (not both) to one side of the
Inside Wiring.
3.
Turn the Mode switch to
STRESS TEST
.
4.
The Ground is good if the meter’s black scale reads 40-45 or higher.
Stressing the pair
1.
With the Green and either the Tip or Ring leads still connected, connect the
remaining Tip or Ring test lead.
2.
With the meter still in the
STRESS TEST
Mode, determine the quality of the
pair by comparing the meter reading on the black scale to the following
Noise Metallic levels.
Stress Test: Measured in dBrnC
Scale:
0 to 90 dBrnC
Acceptable:
0 to 20 dBrnC
Marginal:
20 to 25 dBrnC (test further)
Unacceptable:
25 dBrnC or higher
Resistance Testing – Fault Isolation
1.
Disconnect
ALL
the subscriber’s equipment after finding a high (20+)
reading.
a.
If the Stress reading drops, the fault is in the phones.
b.
If the Stress reading remains the same, the fault is in the Inside Wiring.
2.
If the fault is in the phones, reconnect each phone (one at a time) until the
phone(s) have been isolated.
3.
If the fault is in the Inside Wiring, remove and
Stress
each Inside Wire (one
at a time and with the phones disconnect) at the station protector until the
wire(s) have been isolated.
