1.3.2 Laying of optical fiber cables (part four)

Maintaining bending radius

1. Always maintain the minimum permissible cable bend radius. Dropping below the minimum bending radius leads to damage of the PROFIBUS cable and changing of its optical properties. The minimum bend radius can be found on the manufacturer’s data sheets.
   
   
   
   
2. During laying, the PROFIBUS cable is mechanically subjected to additional tensile forces. For this reason, a larger bend radius must be maintained during pull-in than when in its final position. Pulling PROFIBUS cable around a corner is a particular problem. For this reason, you must use pulleys to avoid any excessive stress and sharp bends when pulling PROFIBUS cables around corners..
   
   
   

Avoid looping

1. Pull the PROFIBUS cable straight off the drum, which should be free to rotate. Never unwind cable from a stationary drum..
   
   
   
   
2. Use auxiliary equipment, such as drum feeders or rotary plates for this purpose. This prevents the formation of loops and associated cable kinking. In addition, it prevents the PROFIBUS cable from being twisted.
   
   
   
   
3. If a loop should have occurred, wind the loop out of the PROFIBUS cable. Do not simply pull the PROFIBUS cable straight since this would damage the optical PROFIBUS cable!

Avoid sharp edges

1. Sharp edges can lead to PROFIBUS cable damage. For this reason, remove sharp edges and burrs with a file or a triangular scraper. This includes cut edges on cable trays.
   
   
   
   
2. Protect edges at the end and corners with edge protection strip.