Communications line testing

A communications system having a capability for testing the working condition of spare line pairs, the system comprising:

• an electrically conductive communications cable which extends from a node to a remote distribution point and has a plurality of spare line pairs,
• a test access facility associated with exchange equipment terminations,
• means for applying test signals to the test access facility,
• means for determining the relative conditions of the test signals when applied on the tested line pair;
• a plurality of identical test devices connected between the ends of a respective plurality of spare line pairs at the remote distribution point, the other ends of the respective plurality of spare line pairs being terminated at the node in respective exchange equipment terminations
• the means for applying signals being arranged to apply signals of both polarities via the test access facility to a selected one of the spare line pairs connected to its respective test device;
• and
• the means for determining being arranged to determine from the relative conditions of the test signals whether the line pair under test is in working condition.

A method for conditioning spare conductive line-pairs in a communication signal distribution system so that a spare line-pair can be subsequently tested from a proximal end distribution site before being removed from its spare status and utilized by connection of its distal end for utilization, said method comprising the steps of:

• connecting a respectively corresponding substantially identical test unit to the distal end of each of a plurality of spare line-pairs in a communication system and leaving said test units so-connected until a designated spare line-pair is to be utilized;
• prior to connection of the distal end of the designated spare line-pair for utilization, applying test signals to the proximal end of the designated line-pair and thereby ascertaining its operational status;
• and
• if the designated line-pair tests as operational, then disconnecting the test unit from its distal end and re-connecting the distal end of the designated line pair for utilization.