Voltage Safety Warning (Live Sample); Determining And Measuring Vp Values; Selecting A Library Cable Or Setting Vp; Cable Library - Chauvin Arnoux CA 7024 Manual De Instrucciones

4.7

Voltage Safety Warning (Live Sample)

The Fault Mapper™ is designed to work on non-energized cables only.
In this situation the operator should immediately disconnect the Fault Mapper™ from the
cable.
* * * * * * * * * * * * * * * * * * *
Voltage Detected
* * * * * * * * * * * * * * * * * * *
4.8

Determining and Measuring Vp Values

Velocity of Propagation (Vp) values are characteristic of each cable type and brand.
The Vp is used to measure the length of a cable and to measure a fault location. The more
accurate the Vp, the more accurate the measurement result will be.
The cable manufacturer may list the Vp on their specification sheet or may be able to
provide it when asked. Sometimes this value is not readily available, or the user may wish to
determine it specifically to compensate for cable batch variations, or for special cable
applications.
This is quite easy:
1. Take a cable sample of exact length increments (ft or m) longer than 60ft (20m).
2. Measure the exact length of the cable using a tape measure.
3. Connect one end of the cable to the Fault Mapper™ (see § 4.10). Leave the end
unterminated and make sure the wires do not short to each other.
4. Measure the length and adjust the Vp until the exact length is displayed.
5. When the exact length is displayed, Vp is established.
4.9

Selecting a Library Cable or Setting Vp

Press the Vp and Vp buttons to move up and down through the library.
! ! ! !
! ! ! !
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4.9.1

Cable Library

Appletalk Ethernet 9903
Berden 8102 Ethernet 9907
Berden 9903 IBM 1/2A/6
BT2002 IBM Type 3
CAT5 STP IBM Type 9
CAT5 UTP Mains BS6500
Coax Air Multicore PVC
Coax Air Space RG6/U
Coax Foam PE RG58 (8219)
Coax Solid PE RG58 C/U
Ethernet 9880 RG59 B/U
Ethernet 9901 RG62 A/U
If the cable to be tested is not listed in the library, or a different Vp is required, continue
pressing the Vp button, past the top of the library.
Vp will be displayed with a value, which can be selected from 1% to 99%. If the Vp value is
not known, see § 4.8.
4.10

Attaching a Cable to the Fault Mapper™

1. Make sure that there is no power supply or equipment attached to the cable to be
tested.
2. Check that the far end of the cable is either open or shorted (not fitted with a
resistive termination).
3. Attach the Fault Mapper™ to one end of the cable to be tested.
The cable attachment is via a BNC connector located at the top of the unit. For unterminated
cables use the alligator clip attachment provided.
T/Pair Jelly PE
T/PairPE
T/Pair PTFE
T/Pair PVC
T/Pair Paper 72nF
T/Pair Paper 83nF
Twinax
URM70
URM76
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