Industrial Networking Solutions Tips and Tricks: How to Select Fiber Optic Cables

When selecting fiber optic cables, there are some basic pieces of information you should have:

1. What Speed are your switch ports going to run?

2. What Fiber type does your switch recommend? (62.5, 50 or Singlemode)

3. What is the distance between devices?

4. Where are you going to install the Fiber? (Conduit, Tray, Riser or Plenum)

Let’s start with some basic definitions:

Singlemode - Singlemode uses a single strand of glass fiber for a single ray (or mode) of light transmission. This allows for greater signal distances.

Multimode - Multimode fiber light waves are dispersed into numerous paths as they travel through the cable's core Hence, it has more loss, and cannot travel as far as Singlemode. Multimode fiber comes in multiple variations: 62.5 micron (OM1), 50 micron (OM2) and 50 micron (OM3). Each one of these performs at varying degrees depending on the distance and signal type being transmitted. For example, 50 micron (OM3) Fiber is Laser Optimized for 10Gigabit Ethernet Applications. The Chart below will tell you how far you can run each transmission speed depending on the Fiber Optic Type chosen. The default Fiber choice for 10/100 Mbps is 62.5 micron. See Chart 1.

We can also make a price comparison between the Fiber types. For example, if we use 62.5 as the baseline, 50 micron (OM3) will be a 50% adder on the price/ft. Comparably, SM will cost 50% less than 62.5, but the connectors will be 50% more expensive.
Next, you need to choose between Distribution or Breakout Style.

Distribution Style Fiber: All Buffered Fibers are protected by one jacket. This allows for smaller OD’s, lighter weight, less cost, and more flexibility. This cable is most often chosen in doing Point-to-Point (Enclosure to Enclosure) installations.

Breakout Style Fiber: Each Fiber has its own individual jacket, under an overall jacket. This cable style typically is more durable than Distribution, but is more expensive, has a larger OD, and is less flexible. This type of Fiber Cable can be terminated Point-to-Multipoint. You can terminate multiple devices via one cable run. Thus, you can “Breakout” the fiber because each fiber has its own jacket. This cable is also good for Direct Buried Applications.