Outside Plant Voice Cabling

Voice Backbone for Haywood Community College

Haywood Community College recently had the AT&T voice service to their 400 building damaged by a construction crew.  Since AT&T’s repair and re-installation of the voice lines would have been prohibitively expensive, they decided to save money by calling CAT Networks & Security to install a category 3 25 pair cable from their 300 building to the 400 building.

The cable run was a total of 850 feet, and 650 feet of it was between the two buildings and required outdoor direct burial cable.  Direct burial cable is manufactured with a water blocking gel inside the cable jacket to prevent water from damaging the wires.  Upon entering the building, the cable must be surge protected from any dangerous voltages that it might have acquired from the adjacent building or any transient voltages between them such as a lightning strike. The Emerson R66P25QC 25 pair protection unit was chosen for its size, price, and reliability.  It offers a 66 block connection both into and out of the surge suppression unit, which fits neatly and securely onto any standard 66 brackets.  The protection unit accommodates industry standard 5 pin protection modules.  We used the solid-state 303M-12F3GA version by Bourns. Once the outside plant cable entered the 300 building, we transitioned to CMR (riser-rated) cable to get to the building’s Dmarc (AT&T demarcation point).  The additional outdoor conduit was necessary since the building had several construction additions.  We used ¾” PVC conduit for this 20-foot section which we fastened to the building exterior in a small cove used for the building’s heat pumps. End to end testing was performed using a Microtest Penta-Scanner+ with a 66 to RJ11 adapter on one end and alligator clips on the other to test for continuity.