MAN_Easyflex_com_eng_01.doc
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3.8.2
Testing a Cable with Known Nominal Velocity of Propagation
NVP or with Known Pulse Propagation Velocity (
v
/
2
)
In many instances the route and characteristics of the cable are known in
which case the nature and position of the fault can located quickly. In such
circumstances proceed as follows:
(1) De-energise or disconnect the Faulty pair and, where appropriate, a
good reference, if possible. When a test has to be performed under
voltage, make sure that the voltage does not exceed
≤
250 V AC/DC.
(2) Use the test leads supplied with the
Easyflex Com
to connect the
Faulty pair to Line 1 and, when appropriate, the good pair to Line 2.
(3) Press key
to switch the
Easyflex Com
on. Menu Measurement will
appear after a few seconds.
(4) Press key (Line) to select the appropriate mode of measurement, e.g.
Diff when a good pair is available or L1 when you test the Faulty pair
alone.
Set to the desired unit of measurement (2nd; Menu; Menu Units),
select a measuring range according to the length of the cable to be
tested, set the pulse velocity to the desired option (NVP,
v
/
2
in m/µs or
ft/µs), set the display mode to ”DUAL ”. The sockets of the instrument
are the zero mark of the cursor. Use the marker to subtract the
supplied interconnect line.
(5) Use keys (
v
/
2
) and the rotary encoder to set the cable-specific
propagation time to the value specific value of the cable to be tested.
(6) Match the
Easyflex Com
to the object under test as described in
section 0.
(7) First of all, try to find the (open) end of the cable.
