Cable Routing, Dressing & Strain Relief

From Leviton:

Cat5e and Cat6 is manufactured to deliver high speed performance to multiple end points and does its job best when it’s handled appropriately. It is not a forgiving material that can be pulled, stretched and stapled without taking its delicacy into account. A light touch on the installer’s part goes a long way towards guaranteeing all system components function properly.

These are some recommended materials for cable installations:

J-hooks and similar cable supports instead of staples for supporting cable along joists.

Velcro tie wraps and cable straps for wrapping multiple cables and for securing to studs.

The methods mentioned above are substantially more forgiving. The labor cost spent tracing and replacing one damaged cable will surpass any lower material expense saved by using less expensive staples.

In the event of routing cabling through studs in a framed wall, use nail-plates to ensure cabling isn’t damaged by drywall screws.

Cable Bend Radius

The cable bend radius for Cat5e or Cat6 must not be less than 4x the cable diameter or about one inch.

Service Loops

A service loop is simply extra cable to be stored and made available in the event of damage to the wire at its termination. Service loops can be used in the event of:

A change of devices- The extra cable can be re-terminated or relocated in the event of a device change.
Errors when installing a connector- Let’s be honest. Not everyone completes a perfect termination 100% of the time. In the event of your termination failing, a service loop will provide enough cable to give it another try.

A minimum 24-inch service loop is recommended for Cat5e or Cat6.

Labeling

It is extremely important that cabling is properly labeled. This will save you the time of tracing cable that is either misplaced or doesn’t perform properly. Proper labeling will include:

A master list of all cables.
A letter or number system for identification.
A label on both ends of all cables.

Labels should be placed near the termination point, but far enough away so that you can re-terminate and not have to replace the label.

Floor Plan

From Leviton’s Basic Residential Installation Guide:

A well-prepared floor plan done in advance of your installation will save you headaches later. It isn’t enough to simply plan one camera installation or cable termination per room. Your plan or a designer’s plan must be thoroughly discussed. This plan should include the specific locations for each type of device (NVR, camera, switch, etc.)

The cable routing.
Allowance for future expansion as your customer’s needs change.
Allowance for changes as the role of various rooms change (a bedroom becoming a home office for example)

Remember that low-voltage structured cable requires gentler handling during installation. When developing the floor plan, be sure that you have sufficient access to pull the cable without damaging it.

This list comes from Brocade’s “Best Practices Guide: Cabling the Data Center”

Over-bundling cables or placing multiple bundles on top of each other can degrade performance. Try to keep fiber and copper runs separated, as the weight from copper cabling can crush fiber cables that are placed beneath them.
Don’t mount cabling components in locations that block access to other equipment within and outside of racks. Also, avoid routing cables over other patch panel ports.
A good rule of thumb is to keep all cable runs under 90 percent of the maximum distance supported for each media type, per relevant standards. This extra headroom will accommodate additional patch cabling to be included in the end-to-end connection.
Install additional cables as spares for both backbone and horizontal runs. Install higher cabling categories to futureproof for forthcoming application requirements.
Don’t leave loose cabling on the floor; it’s a safety hazard. Employ horizontal, vertical or overhead cable managers to route cables within and between racks.
Don’t stress cables by doing any of the following: applying additional twists; pulling or stretching cables beyond specified pull load ratings; bending beyond the specified bend radius; creating tension in suspended runs; stapling or applying pressure with zip ties. Use hook-and-loop-style ties wherever possible.
For horizontal and backbone twisted-pair cabling, preserve the same density of twists in cable pairs up to the point of termination. Use thin and high-density cables wherever possible (per relevant standard specifications) to allow for more cable runs in tight spaces.
As much as possible, test and label every cable as it is installed and terminated. Document all cabling components and links between components and keep this information up to date.
Bundle cables together in relevant groups to ease management and troubleshooting.

Calver Brewer

Structured Cabling Guide