Sample Photos—Cabling, Before and After
Wireless systems have their applications, but—when properly engineered and implemented—you can’t beat a hard-wired local area network (LAN) backbone for distance, noise immunity, throughput, and security. This sample project provides an excellent overview of cabling “don’ts" and “dos.”
BEFORE
This client’s original wiring was comprised entirely of twisted pair throughout the large complex, with several issues:
- Distances to many of the users from the central computer/communications room/hub were much longer than the recommended 100 meters.
- The building was rife with electro-magnetic interference (EMI) from the production equipment; this EMI could even be heard as static blasting over radios in cars parked near the building outside.
- Many of the runs had been extended via splices—an unacceptable practice for data.
- A number of connections had failed altogether so that new connections were improvised by running long, unprotected patch cords over walls from office to office.
- The documentation was outdated so that it had become very time consuming to troubleshoot the failing connections.
INSTALLATION
After analyzing the situation, we accomplished a number of improvements:
- We replaced multiple out-of-spec twisted pair connections from the hub with Gigabit fiber optic cables in a hub-spoke network of managed Gigabit Ethernet switches. Each far-flung office area (such as the maintenance room wiring closet) was equipped with its own remote-managed switch, connected via fiber to the hub switch in the central computer/communications room. Each fiber connection could handle far more data than the multiple twisted-pair cables they replaced—with the added benefit of total immunity from the electromagnetic interference (EMI) generated by the factory equipment.
- For maximum integrity we had each fiber cable pre-assembled to a carefully-determined custom length and tested in the factory, with reserve slack protected in a special coil and stored in the plenum area at each end.
- To further protect the fiber optic cables, we had them installed within custom steel conduit where they passed through concrete walls and a tunnel between buildings.
- We procured new twisted pair wiring and/or patch cords for installation from each second-tier switch to its end user devices. One administration area had two levels with multiple walled offices best served by co-locating a patch panel with the switch in one office, then running cables through the walls to wall plates in each of the other offices.
- We developed a standardized system of color-coded patch cords to aid with future troubleshooting and maintenance.
- We thoroughly documented the entire system and posted color-coded diagrams in each office to aid in future connections and diagnostics.
- To minimize labor expense and facilitate future troubleshooting and expansion, we trained the client's maintenance staff—already accustomed to working in the high ceiling areas and familiar with the overhead fixtures—to perform as much as possible of the installation. We then completed cable testing and final hardware connections on follow-up visits.
pre-assembled with
pull-tie to protect end
during installation.
pull-tie being removed
in order to connect
duplex end to Gigabit
managed switch.
Connection of new unshielded twisted pair (UTP) Category 5e cables (yellow for even numbered ports, gray for odd numbered ports) to distribute incoming data from orange fiber optic cable to nearby offices via switch and patch panel, ready for mounting in enclosure high on wall to protect cables.
AFTER
through tunnel between buildings.
