4..10 Testing a Cable
After setting the Vp value and cable impedance (Z) to match the tested
cable, attach the Fault Mapper Pro
Press the
TEST /
The following display shows a cable with impedance anomalies on it.
The vertical cursor line is moved left and right along the line of the trace by
pressing the and buttons.
To determine the distance to an event, position the cursor at the beginning
of the event and read off the distance as shown below.
On the fault curve shown in the previous two screens, a low impedance
event occurs at 210 ft, shown by a downward spike on the curve, and a
high impedance event occurs at 413 ft.
The open end of the cable is shown as a large positive spike This is used
to determine the end (length) of the cable.
Fault Mapper Pro
button, to get to the test screen.
Vp=72% Z=100Ω
413ft
Vp=72% Z=100Ω
210ft
Vp=72% Z=100Ω
413ft
®
Model CA7026
to the cable, as described in § 4.9.
®
1