The Pros and Cons of Rebuilding with Fiber

1
The Pros and Cons of Rebuilding with Fiber

• Best Practices for Installation, Care and Handling

Presented by James Graham Sr. Broadcast
Engineer Wight State University
2
QED

• Quantum Electrodynamics is the area of physics
  that studies the properties of the interaction
  between light and matter.

3
Rod in water

• Two mating materials with different indexes of
  refraction will refract a greater percentage of
  photons than the same thickness composed of only
  one material with a consistent index of
  refraction.

4
Rod in water

• Breaks in fibers
• Fusion Splice

5
Fiber as isolation

• EMF
• Lightning
• Ground Loops
• Inductive Coupling

6
Do not use extremely short fibers for equipment
that expects longer runs.

• Reference cable is 10 meters (33ft) with a
  minimum 3 inch coil for excess.
• Saturation of input

7
Do not use extremely short fibers for equipment
that expects longer runs.

• Undesired pathways / Opaque cladding

8
Measurement errors due to mode field diameter
mismatches

• 50 um and 62.5 um
• Gainers
• Exaggerated Losses

9
Installation

• Choose the proper connector for your cable type
• Single-mode connectors may work on multimode
  fiber but not recommended.
• Multimode connectors probably will not work on
  single-mode fiber at all.

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Installation

• Choose the proper connector for your cable type
• ST, SMA, SC and FCPC often selected by default to
  match existing infrastructure or equipment.
  Otherwise perform a benefit analysis to select
  the best connectors for your facility.

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Installation

• Connector installation and care
• Do not share mechanical tools between users.
  Wear and calibration settings will vary according
  to individual technique.
• Do not use calibrated stripping tools that have
  been dropped or damaged until they have been
  verified to be calibrated and in good working
  order.

12
Installation

• Connector installation and care
• Remove the minimum amount of polymer coating as
  required for proper termination. Excess exposed
  fiber will increase the risk of damage or
  inducing flaws.

13
Installation

• Connector installation and care
• Connectors should be installed immediately after
  stripping and cleaving to prevent dust and other
  air borne contaminants from accumulating.
• Polished ends of fiber connections should always
  be protected from contamination and damage.

14
Installation

• Choose the proper type of fiber for the
  application
• Distance
• Bandwidth (Single-mode vs. Multimode vs. both)
• Signal Content
• Baseband vs. RF
• Digital vs. Analog

15
Installation

• Choose the proper type of fiber for the
  application
• Splicing different manufacturers and types
• Plenum
• Innerduct
• Buried vs. Aerial
• Blow in vs. Pull in

16
Installation

• Marking buried cable locations
• Warning tape
• Trace wire
• Electronic marking systems

17
Installation

• Do not exceed specified pull force
• No trucks
• Load limited cable pulling rig with force gauge
• Trenching / Unroll / Blow in / Horizontal boring
• Install service loops

18
Installation

• Do not exceed the loss budget
• Cliff effect for optical receiver
• Typical connector / Splice loss 0.5 dB 0.75 dB
• Attenuation is about 4.5 dB per km at 850nm
• Attenuation is about 3 dB per km at 1300nm
• Attenuation is about 1 dB per km at 1500nm

19
Installation

• Do not exceed the maximum recommended fiber
  length
• Bandwidth is reduced proportionally to distance
• Highest frequency supported is related to
  available bandwidth

20
Installation

• All system designs and specifications should
  include detailed cable management solutions and
  handling procedures including storage
  requirements, bend radius limits and stress
  maximums for pulling stress and drop heights,
  etc

21
Installation

• After each project is completed a thorough
  implementation process audit should be completed
  to identify issues that should be addressed in
  future installations.

22
Installation

• If possible all fiber strands should be tested
  and documented on all major installations while
  the fiber is still on the reel to identify any
  manufacture defects or shipping damage. This
  will help identify damage incurred during
  installation and will give you possible recourse
  if the fiber is installed and does not work as
  expected.

23
Fiber Damage

• Flaws in the surface of the cladding are largely
  responsible for mechanical strength and may lead
  to failure.

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Four types of damage

• Fatigue Damage is the degradation of a fiber over
  time due to applied stress. Exceeding stress
  limits will have a cumulative effect and may lead
  to failure months or years later. Fiber should
  always be installed as straight as possible with
  as minimal mechanical and environmental stresses
  as possible.

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Four types of damage

• Fatigue Damage
• Tensile stress
• Torsional stress
• Heat stress
• Impact stress (drop, rough handling)

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Four types of damage

• Fatigue Damage
• Bending stress. Increased attenuation will
  result from a bend diameter of 20mm (1 inch) or
  less. However the minimum recommended diameter
  is greater than 25mm due to the mechanical stress
  limits and development of stress fractures.

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Four types of damage

• Compressive Damage is due to compressive stress
  which induces flaws.
• Damage to coating
• Damage to glass
• Zip ties
• Tools, squeezing force

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Four types of damage

• Compressive Damage
• Components and equipment
• Doors
• Stepping on

29
Four types of damage

• Abrasive Damage is caused by scraping against
  sharp or rough surfaces.
• Removal of coating
• Creation of flaws in cladding
• Uncontrolled surfaces (floor, racks, etc)
• No solvents (acetone, acids, oxidizers)
• Holding tools, metal vs. plastic or rubber

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Four types of damage

• Abrasive Damage
• Tool inspection for wear, damage, burs, nicks,
  corrosion, clean.
• Fingernails and jewelry
• Non-abrasive cleaning materials. Use appropriate
  lint free cloth with high purity alcohol, limit
  cleaning passes on each fiber and limit the reuse
  of the same cloth.

31
Four types of damage

• Particulate Penetration is a result of materials
  such as scrap fibers or metal splinters that are
  forced through the polymer coating, usually due
  to poor cleanliness of work areas and subsequent
  processing of fiber for installation or
  termination.
• Damage to coating
• Damage to glass

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Four types of damage

• Particulate Penetration
• Cleanliness
• Cutting or breaking fiber over work surface
• Uncontrolled surfaces (floor, racks, etc)
• Static Electricity (particles and tangles)

33
Hazards as identified from the Material Safety
Data Sheet

• Dust or powder from stripping outer coating layer
  can be irritating to eyes, skin, respiratory
  system and gastrointestinal tract.
• Do not rub eyes while handling and keep work area
  clean.
• May cause cuts to skin and splinters may require
  removal.

34
Hazards as identified from the Material Safety
Data Sheet

• May cause lung damage if inhaled in sufficient
  quantities. Use a vacuum cleaner with HEPA
  filter when cleaning work area.
• Wear safety glasses with side shields.
• Wear leather work gloves when appropriate while
  handling.

35
Hazards as identified from the Material Safety
Data Sheet

• When disposing of waste materials enclose in an
  appropriate container for disposal, such as a box
  or multiple layered bag.