Vonaq RapidTrace 1200, Руководство пользователя

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4.5 Typical Fault Displays
The following diagrams show typical fault traces to assist you in the
identification of faults using the RapidTrace 1200:
OPEN
CONDUCTOR
SHORTED
CONDUCTOR
SPLICE
BRIDGE TAP
SPLIT/
RESPLIT
WET SPLICE/
WATER
FRAYED
CABLE
WATER
INGRESS
TAP
SPLITTER
4.6 Typical Cable V.P and Impedance Values
Type Vp Z Type Vp Z
Cat5 STP 72 100 T/Pair Jelly PE 64 100
Cat5 UTP 70 100 T/Pair PE 67 100
Coax Air 98 50/75 T/Pair PTFE 71 100
Coax Air Space 94 50/75 T/Pair PVC 58 100
Coax Foam PE 82 50/75 T/Pair Paper 72nF 88 100
Coax Solid PE 67 50/75 T/Pair Paper 83nF 72 100
4.7 How to determine Vp settings
If the TDR RapidTrace 1200 is to be used with a cable type for which the
Vp is unknown, this must first be determined.
1. Take a sample of the cable at least 100m or 300ft long.
2. Measure the actual length of cable using a rule or tape measure, or
some other reliable method.
3. Connect the TDR RapidTrace 1200 and adjust the Vp setting such
that the tester gives a correct reading of the sample length.
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