Megger PFL22M1500 Series, Руководство пользователя

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MTDR USER GUIDE
AVTMPFL22M Rev 1 April 2011
49

“Range”. Select by depressing jog-dial,
where the TDR ranges can be selected
Allows the operator to set the MTDR to
the desired range from 100m to 55km
(fixed ranges).
It is recommended that a higher
range than the anticipated length of the cable is
used.

Scroll to “Pulse Width. Select by
depressing jog-dial, where you will see
options of selecting the width of the
MTDR output pulse.
Allows the operator to set the pulse width
of the outgoing pulse from 5ns to 10µS or
select Auto whereby the pulse width is
automatically selected as determined by the
range selected.
 Scroll to “Gain” , select by depressing jog-
dial.
Allows the operator to adjust the amount
of gain to be applied to the displayed trace.

Scroll to “Velocity” , select by depressing
jog-dial.
Allows the velocity factor to be selected.
This is an important factor as it is this that
determines the electrical speed of the cable,
hence any measurements are made based
on this parameter. Units will be as
determined in preferences.
NOTE: If the Cable length is known, then Velocity can be verified. Place the left
cursor at the start of the cable and the right cursor at the Cable end and
adjust the Velocity. When the Distance shown for the right cursor
matches the known Cable length, the velocity is set to its correct value.