Why it is Important to Keep Fiber Optic Connectors Clean

One of the most overlooked aspects of fiber optic maintenance and troubleshooting is keeping the fiber optic connector endfaces clean. As we will discuss later in this article, a dirty fiber connection can either slow down or completely inhibit network traffic.

Keeping fiber connections clean is different from any other type of cleaning due to the relative sizes of the connectors compared to the particles and contaminants that typically reside on them. Also we need to be diligent in their maintenance by cleaning the connectors every time before they are mated and after each un-mating. Static charges attract dust to the fiber connectors and prevent them from falling off even when blown with a can of compressed air. As we will see later on in this article, dust caps are primarily used to protect the ferrule and do not offer fail safe protection from particle matter. In some cases, the dust caps can actually make a clean connector dirty due to their tendency to keep a static charge. In addition to dust, there are other contaminants like dried liquid compounds that need to be dealt with on the cleanings. 

When troubleshooting fiber, it is important to remember that dirty fiber connections can easily cause a slowdown or a complete shutdown of data traffic. An important tool for a network manager to have is a 200 or 400 power microscope. Dirty fiber connections should not be overlooked when troubleshooting fiber. CAUTION: Never look directly into an illuminated fiber. Laser light can cause permanent eye damage. 

 Frequently Asked Questions:

Q1: We know that dirty connections can cause attenuation. Can the dirty connections can also cause bit errors and/or slowdown of the network?

Yes, dirty connectors will cause Bit Errors because the contamination degrades the signal quality. In optical networks, the signal comes in the form of a beam of light travelling through the fiber’s core. The fiber’s core has a refractive index value of N1. When the light beam comes into contact with end face contamination, it is now coming entering a second medium which has different refractive index value which we will call N2. The signal experiences changes to both reflection and fraction as it enters the second medium. The signal is basically travelling down the fiber core as a sine wave. The contamination changes that sine wave by reducing the amplitude of the sine wave and spreading its wavelength because of the reflection and fraction that happens when the signal enters the second medium or N2. If you remove the contamination, you keep the light s