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Handle cable with care
Limit bend radius whenever possible
Avoid torquing down connector ends
Avoid twisting assembly
Avoid bending the assembly
Avoid pulling by the connector
Never allow assembly to support its own weight
Avoid the use of cable ties
Avoid subjecting the connector to axial loads
Wrap connectors when installing outside
Always provide adequate drip loops
Take extra care on short assemblies
Handle cable with care:
IW cable assemblies are designed to operate at the highest electrical performance level. High performance cables such as these require special handling procedures to ensure optimum electrical performance. Many of these handling procedures are outlined in detail within this document. However taking just a few basic preventative measures during handling could significantly extend the life of the assembly. You should always take care to prevent anything from being placed on an assembly. This could result in internal damage caused by compression. Also, to prevent cable from bending below it's minimum bend radius as this will cause the cable to kink which results in internal damage.
Limit bend radius whenever possible:
Although IW cable assemblies can accommodate a very small bend radius, it is recommend to use the widest possible bend radius to fit the application. This will help to keep mechanical stresses low through the bend and prolong the life of the assembly.
Avoid torquing down connector ends until both connectors are mated in position:
It is important to first hand tighten both connectors into position before any torque is applied. If a connector is torqued down before the assembly is routed into position excessive torsion could be applied at the torqued connector's termination during the routing. These torsion forces could cause the dielectric to change its mechanical position at the connector termination. This could ultimately lead to an electrical failure.
Avoid twisting assembly to orient connectors:
When installing assemblies with right angle connectors do not twist the cable or connectors to orient it with the mating connectors. Twisting the assembly could result in mechanically changing the dielectric position at the termination and ultimately lead to an electrical failure. Assemblies should be purchased with a specific connector offset angle to match the proper mating connector. If an offset angle needs to be changed during assembly installation, proper adjustment procedures can be obtained by calling IW's Technical Support.
Avoid bending the assembly at the connector termination:
A cable assembly should never be bent at the back of the connector. Applying a bend prematurely at the end of an assembly and allowing the bend to encompass the connector could lead to the build up of excessive cable forces against the connector and through the bend area. The applied forces will cause the cable to kink. Electrical degradation and possible failure may result.
Avoid pulling an assembly through channeling by the connector end:
Never pull an assembly by its connector when routing it through a frame work, channeling or building. Doing this could mechanically damage the connector termination. The assembly should always be pulled by the cable itself. Furthermore, the installation should be assisted by pushing the assembly through the channeling while the cable is pulled. Additionally, it is less stressful to the assembly if it is installed in phases (through individual sections) rather than a single run across the entire routing length.
Never allow an assembly to support its own weight when routed in a vertical installation:
Never allow an assembly to hang freely by its own weight; Clamp down the cable at equal intervals along its length. Cable hangers can be used when it is not possible to clamp down the assembly in a vertical installation provided the assembly has been reinforced for such an installation. Using multiple hangers whenever possible is also recommended to help evenly distribute the assembly's weight along the run.
Avoid the use of cable ties.
Most high performance cables use an air filled dielectric core. This makes the cable very soft. Therefore any compressive load applied to the cable has the potential of collapsing the dielectric core within the cable. Cable ties and tie wraps are not recommended for this reason. They offer virtually no load distribution and consequently focus very high compressive forces through the tied down area. A concentrated force such as this almost always deforms the cable and significantly degrades assembly performance. For best holding results with minimal clamping forces, IW recommends rubberized clamps. Be sure to select a clamp that will apply a minimum amount of compression force while still offering the desired holding strength. Selecting a clamp that it too small can do as much damage to an assembly as a cable tie.
Avoid subjecting the connector ends to cable axial loads:
Cable assembly life can be increased by clamping down the cable a few inches from the connector ends in applications where the cable will be moving (such as a moving antenna) or where a high vibration condition exists. Clamping the cable down at the cable ends reduces mechanical loads applied to the connector when the cable is moved.
Always wrap connectors in weather proofing when installing outside:
All cable connections that will be subjected to rain and snow should be wrapped in a weather proofing material. A self fusing silicone tape is recommend to create a weather tight seal over the connection. If weather precautions are not taken, water will eventually work its way into the connector assembly causing high insertion losses.
Always provide adequate drip loops:
Always allow for a drip loop in outside applications to prevent water from flowing down the cable and onto the connector. Over time the water could work its way into the connector assembly causing high insertion losses.
Take extra care on short assemblies:
- Always bend assemblies around mandrels whenever possible:
The use of mandrels or wheels will help to evenly distribute bending loads applied to the cable. This is the preferred method for bending cables. - Take caution when bending cables by hand:
Sometimes bending a cable by hand is the only option. In this case the following method should be used;
- Start at bending point keeping hands close together.
- Bend the cable a little at a time working in an outward direction along the bend.
- Return to the center point of the bend and work in an outward direction making the bend a little tighter.
- Continue to return to the center of the bend, and working outward until the desired bend is reached.
- Take caution bending cables under 12" in length.
An assembly that is 12" in length and smaller can be very rigid depending on the cable type. The cable becomes rigid because its inner and outer conductors are fully (mechanically) terminated to the cable connectors. The cable is terminated this way to yield maximum electrical performance. Unfortunately, it minimizes the bending characteristics of the assembly because the cable is too short to accommodate the total material volume displacement needed for a typical bend. Often, the minimum bend radius can not be achieved without damaging the assembly. Therefore, short cables should only be used in applications where slight jogging bends will be used. A longer assembly that uses a service loop should be considered as a replacement for a short cable in situation where a tight or sharp bend is needed.
Cable Handling - Phase Stable Cables - Cross Reference - Build a Cable
