Patent ID: 7276913

Claim:
A cable tester for testing cable to determine a cable status, comprising: a mode selector that selects one of a first operating mode and a second operating mode: a pretest module that senses activity on the cable and that selectively enables testing based on said sensed activity when in said first operating mode and that enables testing when in said second operating mode; and a test module that is enabled by said pretest module, transmits a test pulse on the cable, measures a reflection amplitude and calculates a cable length, wherein said cable status includes at least one of an open status, a normal status and a short status, wherein said test module determines said cable status based on said measured amplitude and said calculated cable length, and wherein when said pretest module is in said first operating mode, said pretest module enables testing if activity is not detected during a first period and if activity is detected during said first period and is subsequently not detected for a second period after said activity is detected.