Baur Sys compact 2000 M pro - Evaluating TDR Reflection Images

Cable fault pre-location Syscompact 2000 M pro
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Procedure
On the IRG 2000
 Follow the user manual for the IRG 2000 time domain reflectometer.
1. Connect the IRG 2000 to the test object.
Further information about connection and earthing is given in the user manual for the IRG
2000.
2. Switch on the IRG 2000 with the key.
3. Press the MENU key.
4. Use the rotary knob to select the Mode menu item and press the rotary knob.
5. Use the rotary knob to select the desired TDR method and press the rotary knob.
The method is selected.
6. To start the measurement, press the rotary knob for 2 seconds.
 TDR method TDR: The measurement is performed. The trace is displayed. The
cursors are positioned automatically on the cable fault or cable end.
 TDR method TDR Continuous: The measurement is started. The measured values
are recorded permanently.
 To stop the measurement, use the rotary knob to select the Stop button and press the
rotary knob.
The trace is displayed. The cursors are positioned automatically on the cable fault or
cable end.
 TDR method TDR Trigger: The IRG 2000 is ready. A measurement is performed as
soon as the measuring device connected to the Trigger Input port detects a current
that lies above the set threshold value. The trace is displayed. The cursors are
positioned automatically on the cable fault or cable end.
12.3.5 Evaluating TDR reflection images
The reflections can be divided into two groups:
 Normal reflections
Even healthy phases can show reflections. These reflections are caused by
inhomogeneities such as bends, connection points, meeting points of cable sections with
different insulations or joints.
 Reflections caused by faults
A faulty phase shows normal reflections as well as reflections caused by faults. Due to the
damping losses in the cable, a fault that is far away reflects a smaller pulse than a fault that
is close by.
To differentiate normal reflections from reflections caused by faults, it is always
recommended comparing the traces of a faulty and a healthy phase.