Cable tester

A cable tester that tests cable including multiple pairs and that determines a cable status of the cable, comprising:

• pretest means for sensing activity on one of the pairs and for selectively enabling testing based on said sensed activity is not detected for a first period;
• and
• test means, that is enabled by said pretest means, for transmitting a test pulse on said one of the pairs, measuring a reflection amplitude and calculating a cable length,
• wherein said cable status includes an open status, a short status, and a normal status, wherein said test means determines said cable status based on said measured amplitude and said calculated cable length, and wherein said test means measures received signals on at least one other pair after transmitting said test pulse on said one of the pairs, compares said received signals on said at least one other pair to a predetermined threshold, and determines a pair short status between said one of the pairs and said at least one other pair if said received signals exceed said predetermined threshold.

A method for operating cable tester that tests cable including pairs and that determines a cable status, comprising:

• sensing activity on one of the pairs;
• selectively enabling testing based on said sensed activity;
• transmitting a test pulse on said one of the pairs;
• measuring a reflection amplitude;
• calculating a cable length, wherein said cable status includes an open status, a short status, and a normal status;
• determining said cable status based on said measured amplitude and said calculated cable length;
• measuring received signals on at least one other pair after transmitting said test pulse on said one of the pairs;
• comparing said received signals on said at least one other pair to a predetermined threshold;
• and
• determining a pair short status between said one of the pairs and said at least one other pair if said received signals exceed said predetermined threshold.