When testing the twisted pair cable, the possible problems are: the near-end crosstalk is not passed, the attenuation is not passed, the wiring diagram is not passed, and the length is not passed:
1. Causes of inpass of near-end crosstalk may be:
1) there is a problem with the endpoint;
2) Short Circuit at the remote connection point;
3) string pairs;
4) External Noise;
5) The performance of link cables and connectors is incorrect or is not the same type of product;
6) there is a problem with the end connection quality of the cable.
2. possible causes of attenuation failure include:
1) The length is too long;
2) The temperature is too high;
3) There is a problem with the connection point;
4) The performance of link cables and connectors is incorrect or is not the same type of product;
5) there is a problem with the connection quality of the cable.
3. Possible reasons for dispassing the wiring diagram:
1) the two ends of the joint are open circuit, short circuit, cross, open circuit rupture;
2) cross-connection error (some networks need to be cross-connected between the sender and acceptor. When a test link is built for these networks, the wiring diagram of the test will be crossed due to the inter-connection of the device line ).
4. possible causes of failed length:
1) NVP settings are incorrect. The NVP can be determined by a known good line and re-calibrated n v P;
2) The actual length is too long;
3) open or short circuit;
4) the total length of the device connection and cross-wiring is too long.
5. tester Problems
1) if the tester is not started, the battery can be replaced or charged;
2) The tester shall not work or shall not perform remote calibration. Both testers shall be able to start and have enough battery or change the test line;
3) if the tester is set to an incorrect cable type, the tester parameters, types, impedance and nominal transmission speed should be reset;
4) The tester is set to an incorrect link structure, and the tester is set to a basic link or path link as required;
5) The tester cannot store the automatic test results, confirm that the selected test results are named unique, or check the available memory capacity;
6) The tester cannot print the stored automatic test results. The interface parameters of the printer and the tester should be set to the same, or the validation test results have been selected as printed output.