EXFO FTB-610 Wideband Copper Test Module - Manual (Page 195)

Copper Test 187
12 TDR Test
The TDR test is a useful tool on the large FTB screen to locate cable faults.
The test is used after a fault has been identified running other tests, since
TDR reacts to all faults and conditions on a typical cable pair, revealing
multiple events, some of which may be acceptable conditions. TDR first
attempts to find the length of the circuit and then searches all ranges from
shortest to longest for significant events. Upon completion, the test selects
the nearest major event, sets the range to match, and aligns the cursor with
the event. TDR can see events as close as the ends of the test leads. The
graph controls allow you to see the reflections and their distances so that
you can find and resolve faults.
There are 3 modes of operation to choose from:

Auto TDR

Manual TDR

Xtalk TDR