Greenlee PE945 Manual De Instrucciones página 12

Using the Test Set for Troubleshooting Circuits
Some general troubleshooting procedures and tips are provided here. These procedures may require
other tools or equipment that are specific to the communications system installation trade. For a
complete selection of VDV (voice-data-video) tools, please refer to a Greenlee full-line catalog or visit
our website at www.greenlee.com.
Symptom*
Test set alarms
Cross-talk
Cross connection
Noise
Power hum
* Wet cables may cause most of these symptoms and may cause multiple symptoms to appear at
the same time.
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Possible Cause /
Troubleshooting Step
Telephone wire
contacting a power line
Split pair
Direct wiring fault
Hiss (white noise);
pulse dialing causes a
momentary change in the
sound of the noise
Popping, crackling
Momentary or impulse
noise
Cable imbalance
A long run of telephone
cable near a power line
Ground fault
Explanation
This is a potentially hazardous situation!
If the test set produces the excessive DC voltage
alarm (low pitch, low pitch, low pitch) or the AC
line voltage alarm (constant ringing), remove the
test set from the line carefully and immediately!
A split pair (a circuit made up of wires from two
separate wire pairs) will be unbalanced and prone
to cross-talk.
Check for crossed pairs.
This is probably due to water in the cables.
The customer has an older carbon transmitter type
of telephone.
This may be due to an unbalanced cable, nearby
power switch gear, or similar equipment.
Break the circuit down into sections and check each
section for an imbalance.
Contact the local electric utility.
Check for the presence of voltage. If voltage is
present, measure the level. If it is typical line
voltage, contact the local electric utility.