Terminating UTP on 66 blocks made easy

July 1, 1997
Terminating a large unshielded twisted-pair (utp) riser plant on 66 blocks in a building can take considerable time and effort.

Dennis Mazaris,



Terminating a large unshielded twisted-pair (utp) riser plant on 66 blocks in a building can take considerable time and effort.


Structure a repetitive method where utp cables can be terminated quickly and efficiently.


1) Strip jacket from utp riser cable (25-pair cable count or higher). Remember to strip off enough of the jacket to provide an adequate service loop behind the 66 block. This loop is necessary in case a pair is terminated in a wrong position on the block and must be reterminated.

2) In combination with step one, make sure that the 25-pair cable is sorted into the proper 66-block locations.

3) Sort 25 pairs into the five color groups--white, red, black, yellow, and violet--along with the binder group for larger pair counts.

4) Start at the bottom of the block, inserting color groups into the 66-block clips in the following order: violet, yellow, black, red, and white.

5) Make sure that there is adequate space (minimum of 5 pairs) between colors for terminating pair groups.

6) Insert individual pairs into the 66 clips starting at the bottom of the 66 block. Begin with the violet group. By inserting wires this way, you avoid having cable pairs in your way.

7) After all pairs are inserted into the 66 clips, start from the top of the 66 block and begin terminating from top to bottom.

Click here to enlarge image

Once the 25-pair unshielded twisted-pair (utp) cable is sorted into proper 66-block locations, sort wires into appropriate color groups. There will be five pairs in each group. Then remove pairs from their group and insert them into the proper clips.

Dennis Mazaris, registered communications distribution designer (rcdd), is the principal consultant for PerfectSite (Sterling, VA), a consulting firm specializing in premises cabling management and design.

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