EN 50173/A1:2000
This amendment to EN 50173:1995 introduces - among others - the concept of the "permanent link". This leads to partial changes in existing text (addition of single words).
New abbreviations:
ELFEXT - Equal level far-end crosstalk loss
FEXT - Far-end crosstalk loss
PSACR - Power sum attenuation to crosstalk loss ratio
PSELFEXT - Power sum equal level far-end crosstalk loss
PSNEXT - Power sum near-end crosstalk loss
Important in this draft amendment:
Permanent link and channel specification.
Permanent links
The performance of a permanent link is specified at and between interfaces to the link. The permanent link comprises only passive sections of cable and connecting hardware. A transition point may also be included in the horizontal subsystem. The interface of the permanent link is the far end of the plug or connecting block, where the cable enters. The cable connected outside of the plug is not part of the permanent link.
Channels
The performance of a balanced cabling channel is specified at and between connections to active equipment. The cabling comprises only passive sections of cable, connecting hardware, work area cords, equipment cords and patch cords.
The interface of the channel is the far end of the work area or equipment cord just before the plug which is connected to the equipment.