OTDR, What does it do?

Optical Time Domain Reflectometers (OTDRs) and fault locators are used to certify new fiber installations and locate faults in deployed fiber optic networks.

OTDR

OTDRs:

  • Scan and characterize fiber optic networks (from one end of the fiber).
  • Display characterized fiber either as a trace showing optical loss and reflectance vs. distance or as a LinkMap providing an icon-based representation of the fiber sections, splices, connectors and any detected faults (breaks or macro-bends).
  • Provide link summary information (end-to-end length, loss, optical return loss).
  • Provide details for each detected connector, splice or fault including event location, event type, loss and reflectance at event and loss to event.

Let’s get a good look at one of the AFL models from their YouTube channel.

OTDRs and fault locators are available for both multi-mode and single-mode networks including passive optical networks (PONs) supporting a range of performance requirements and budgets.

For more information on selecting the proper OTDR check out the AFL selection guide. Once you have a model selected contact your Authorized AFL Distributor Discount-Low-Voltage.com for pricing and availability.

Need the LC connector clip for AFL LC connectors?

When terminating the AFL LC style fiber optic connectors you might need to plug and unplug the connectors from a SFP module repeatedly.

SFP plug into switch

If so, you need to attach that small little clip that holds the two LC connectors together, here’s a look at it from our YouTube channel.

As you can imagine they’re inexpensive and save a headache when plugging and unplugging repeatedly. Order online at Discount-Low-Voltage.com

Fiber Optic Closure for Splicing

Designed with versatility in mind, the LightGuard (LG) 55 sealed closure from AFL offers a variety of solutions including repair, distribution splicing, grounding for Fiber-in-the-Loop applications, and for use as an isolation gap with armored cables.

Here’s a great look from our YouTube channel.

This closure accepts stranded loose tube, Uniflex or ribbon fiber cables in either armored or dielectric configurations and can be utilized in a butt or in-line configuration. The LG-55 closure incorporates a unique cable clamp design sealing the cable, allowing both of the cover halves to be removed without disturbing the contents. In addition, AFL’s Peel & Seal Grommet System is incorporated to ensure a tight fit on various cable diameters, fully sealing the closure and protecting the fiber while eliminating cumbersome tape and washers – making installation fast and easy.

Does armored fiber optic cable need to be grounded? Yes!

How to bond and ground

Understanding how to bond and ground a fiber-optic system with armored cable can be confusing. First, it is important to understand the difference between the terms bonding and grounding. According to the NEC and industry standards, bonding is the permanent connection of metallic parts to form an electrical path that will be conductive and continuous. Grounding is the act of connecting that path to the earth or some conducting body that serves as the earth. When all the components of a system are properly bonded together and grounded to the earth, the risk associated with electrical current harming personnel or damaging property and equipment is reduced.

The first step is to connect/bond the cable armor to a bonding or grounding electrode conductor. This can be accomplished right after the cable is accessed, and the armor is exposed. A bonding conductor or jumper is a short length of conductor, such as copper wire, that maintains electrical conductivity between two metal objects. The bonding conductor is required to be UL-listed and made of either copper or another corrosion-resistant conductive metal. This stranded or solid wire can be insulated, covered or bare. Most cable manufacturers supply an insulated, UL-listed 6-AWG copper strand. The 6-AWG size is preferred for the bonding conductor because that allows it to comply with both the NEC and ANSI-J-STD-607. The bonding conductor can be attached to the armor by the use of a listed clamp, lug or connector, as stated in NEC Article 250.70.

Once the clamp is installed, vinyl tape can be applied around the clamp and exposed armor to protect the installer and the fiber from any sharp edges where the armor is exposed.

grounding armored fiber

For the conductive fiber-optic cable to be fully grounded, the bonding conductor from the cable needs to be bonded to the intersystem bonding termination (if present), or another accessible location per NEC Article 770.100. The intersystem bonding termination is the device that connects the bonding conductors to the building’s grounding electrode and ultimately, to earth. Typically this is accomplished by connecting the bonding conductor to a dedicated path back to the telecommunications main grounding busbar (TMGB) or the telecommunications grounding busbar (TGB). The dedicated path can be a direct run or created by attaching to a rack or cabinet’s bonding system that bonds the rack or cabinet back to the TMGB or TGB. Specific requirements on how the TMGB or TGB are designed can be found in ANSI-J-STD-607 and other industry standards. When the armored cable is correctly bonded and grounded, it minimizes the risk of unwanted electrical current that could potentially harm personnel, property or equipment.

Props to Sara Chase with Corning Cable Systems.