Fiber Optic Cabinets, Cables, Pedestals and Terminals

By: Scot Bohaychyk

Sometimes the basics are what affect the outcome of an installation the most.

Here are some quick basic tips to use when installing pushable fiber into the ruggedized microduct, whether pre-connectorized or not. These techniques have been used to install single fiber, connectorized fiber and multi-fiber assemblies at distances in excess of 800 feet.

While the ruggedized fiber can be pushed in some instances, it typically can be pulled faster. With that being said, there are a couple of items that need to be addressed prior to pulling so the fiber can be installed without damage to the fiber or the connector.

  1. Use either a series of half-hitch knots to tie the pull string on the fiber, stopping just short of the connector. (Figure 1-3) This keeps the pressure on any one point of the fiber to a minimum.
  2. Never tie onto the fiber connector. This will cause damage to or pull the connector off.
  3. Never use tape over the string. The coating on the outside of the fiber is slippery enough that tape usually comes off and clogs up the microduct.
  4. Never….I repeat NEVER remove the protective plastic cover from the connectorized fiber before you place it in the microduct. If you do this, the connector acts as a sort of “cheese grater” down the length of the microduct. It will shave off the inner liner and then those particles bind around the fiber. In some cases, this causes the fiber to become stuck and usually results in a broken fiber.
  5. When using a push/pull technique, make sure to maintain the same rate of feed/pull on both ends. When pulling faster than pushing, you create the same effect that climbers use when rappelling. The fiber actually rubs on all the bends and in effect creates friction to the point where the fiber cannot move. The most common thing that happens here is that the pulling end feels the need to pull harder and the string breaks. Additionally, when you push faster than you pull, the fiber outruns the pull string and binds in the microduct. The effect is the same as pulling too hard, and usually results in a fiber being stuck in the microduct or the string breaking.
  6. Pull with a constant pressure and speed. This helps overcome the initial friction and allows for a smoother installation. You will probably notice as more fiber enters the microduct, the easier the pull becomes. This is because the fiber has a lower coefficient of friction than the pull string.

Follow these basic steps and you will successfully install the ruggedized fiber into the extreme duty microduct.