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M-UM041-04 OTDR 800 6/2020
LOSS:
Event Loss is the loss of the splice, mated pair, or other effect on the fiber considered to be an event. A positive number is the
amount of loss and a negative number indicates a gain normally due to mismatched index of refraction. It is a configurable
threshold for Pass/Fail purposes. The "End" event will always display "N/A".
2-POINT:
2-Point Loss is the loss measured from the end of the dead zone of the previous event to the beginning of current event. The
value in the "Link" row of the table in this column is the link loss, the loss from the beginning of the trace to the event determined
to be the "EOF". This is the value used to determine if the fiber link passes or fails its loss threshold.
dB/Km:
The dB per (dB/...) measurement column is determined by the selected unit of measurement: "KM" for kilometer, "KF" for kilo-
feet, and "MI" for mile. It represents the calculated loss per Km, Kf, or Mi from the end of the dead zone of the previous event to
the beginning of the current event. The value in the "Link" row of the table is the dB loss rate for the total link.
TYPE:
Event Type is the type of event, or the return loss of an event. If the event has no reflection, "splc" is displayed, and if the event
is reflective, the reflectance value is displayed. For the last two events, the first of which is labeled "End", there is not a value
displayed, it simply shows "End". The last row effectively named the "Link" row, the Optical Return Loss for the link is displayed
(System ORL)
8.8 Event Analysis
NOTE:
When using the Event Table or Schematic View, it is necessary to keep in mind that Event Analysis provides approximate
Loss and Distance Measurements to quickly assist in network evaluation. Automatic detection results are not guaranteed
and have their limits by possibly causing erroneous readings or detection failure. User review of the Trace Display is
recommended for final qualitative and quantitative analysis.
8.9 Trace View Screen
EVL
A
RUN
Fig 8.8
DISTANCE INCREMENT INDICATORS
Each line in the grid represents
distance (x axis) or dB scale (y axis)
defined by the Scale/Div chart.
"A-B" CURSOR STATUS / SELECT
Toggles the active cursor between "A" and
"B". When in "EVL" mode, it also toggles
"a" and "b".
ZOOM CONTROL
Displays the zoom level, and also the
values of distance and dB in the vertical
and horizontal grids. Continue to touch the
button to cycle through the zoom levels.
LOSS METHOD
Displays 2 point loss, 4-point/LSA loss,
and dB per Km. Touch anywhere in this
area to cycle through the loss methods.
WAVELENGTH DISPLAY / BUTTON
Displays the wavelength that was tested.
In Dual Mode, this field becomes a button
to swap between the two traces.
EVENT LOSS MODE
Toggling this option on enables the
4-point/LSA loss cursors. "a" and "b"
cursors are shown and enabled for
calculating 4 point loss.
REFLECTIVITY
Displays the measure reflectance value
of the event (if applicable) or N/A if the
event has no reflectance.
"A" CURSOR WITH POSITION DATA
(Active)
"B" CURSOR WITH POSITION DATA
(Inactive)
EVENT NAVIGATION
Jumps to the next recorded event.
CURSOR NAVIGATION
Scrolls the selected cursor.
MAIN TRACE SCREEN
