Fiber Optic Construction Manual

Fiber Optic Construction Manual
Broadband Applications
& Construction Manual
Fiber Optic Cable Products
Table of Contents
Fiber Optic Cable Applications and Construction Manual
Table of Contents
Section 1.................. Introduction
Section 2 ................. CommScope Fiber Optic Cable Types
Section 3 ................. CommScope Fiber Features
Section 4 ................. Storage and Testing of Fiber Optic Cable
Section 5 ................. Installation Safety Issues
Section 6.................. Installation Basics of Fiber Optic Cable
Section 7 ................. Self-Supporting Aerial Installation of Fiber Optic Cable
Section 8 ................. Underground Installation of Fiber Optic Cable
Section 9 ................. ConQuest® Cable-in-Conduit Installation
Section 10 .............. Fiber Splicing
Section 11 .............. Emergency Restoration
Section 12 .............. Midsheath Entry
Section 13 .............. Plant Maintenance
Section 14............... Appendix
0.1
1.1
Introduction
Fiber Optic Cables for the Broadband Cable Plant
CommScope Fiber Optic Cables for Broadband
No matter who you are, no matter what you do at your company, you want one thing more than
anything else - a cable plant that is reliable, durable and economical to install, operate and maintain.
CommScope’s fiber optic cables can do all of this, delivering maximum performance for
a reasonable installed cost. CommScope’s experience with coaxial cable and broadband
service providers has enabled us to design a family of fiber optic cables that is unmatched for
performance, installability and reliability.
In the following chapters, we will show how CommScope fiber optic cables are the perfect solution for your network
and they are no more difficult to install than traditional cable. We will prove that:
for the system buyer, CommScope fiber cables offer the absolute best signal performance at a surprisingly
affordable cost –
for the engineer, CommScope fiber cable’s combination of optical performance
and mechanical stamina is the best possible choice for both systemwide and partial
upgrades while providing the optimal path to a fully digital network –
for the plant manager, CommScope fiber cables offer time-tested designs that
perform for as long - or longer - than any competitive cable –
CommScope
fiber cables offer
innovation that
translates into
a superior
cabling system
for the system designer, CommScope fiber cables offer benefits such as tighter
mode field diameter tolerance for splice compatibility to matched clad singlemode regardless of brand, so they fit
into new or existing construction –
for the craftsman, CommScope fiber optic cables offer innovations like smaller diameter cables that are easier
to pull, strong ripcords to ease fiber access, ‘dry’ moisture barriers that make fiber cables easier to terminate and
other features that speed installation.
CommScope fiber optic cables fit anywhere in the cable plant to ease your migration path to the digital
network. If you are performing a full system upgrade, or just augmenting an existing network, you’ll discover that
CommScope’s fiber optic cables are the obvious choice.
Introduction Design Details and Advantages
Features and Benefits of CommScope Fiber Optic Cables
Like their coaxial counterparts, fiber optic cables are expected to withstand the rigors of life in their application.
CommScope cables are designed to meet that challenge.
Broadband fiber optic cables can be grouped into three categories:
Outside Plant Cables - These cables are designed specifically for outdoor applications, including
aerial, underground and direct burial. They feature polyethylene jackets and may also be armored.
CommScope outside plant cables meet or exceed the Telcordia GR-20-CORE Mechanical and Environmental
requirements, as well as ANSI/ICEA 640 requirements.
Indoor/Outdoor Cables - These cables offer a unique blend of abilities. They are tough enough to withstand
the rigors of the outside plant environment, yet are riser-rated (NEC 770 OFNR) or plenum-rated (NEC 770
OFNP) for indoor use. The advantage of an indoor/outdoor cable is that it can pass from the outside to the inside
intact, with no need to transition from one cable type to another, thus saving the time and labor involved in creating
an additional splice point. CommScope cables meet or exceed the Telcordia GR-20-CORE Mechanical and
Environmental requirements, as well as GR-20-CORE requirements for crush resistance, impact resistance, flexing
and twist/bend.
Premise Cables - These cables are designed to handle the stresses of indoor applications. They include
distribution and cordage cable constructions available with a riser or plenum-rated jacket (meeting the critical
NEC/CEC riser [OFNR] or plenum [OFNP] safety standards).
Dry Stranded Loose Tube Cables – Available with up to 288 fibers
CommScope’s Dry water blocking technology used in stranded loose tube cables provides both ease of
handling and smaller overall cable diameters. By eliminating the use of gel in the core and buffer tubes,
CommScope is able to provide a product that enables you to have an improved work environment that is
cleaner and greener. You can decrease the amount of time it takes to prep the cable while also decreasing
the amount of consumable materials required. These materials include the potentially hazardous solvents that
can be bad for you and the environment. The lightweight cable design offers a smaller overall cable diameter
and smaller buffer tubes which improves ease of handling, maximizes the reel capacity and the available space
inside the enclosure.
1.2
1.3
Introduction
Quality Control and Testing
Precise Production Control and
Rigorous Testing Ensure a Trouble-Free Cable
The superior performance of CommScope fiber optic cables derives as much from the manufacturing process as
from the components. CommScope manufactures its cables in an ISO 9001:2008 registered facility with leading
edge SPC and PLC equipment. Because we have been involved with broadband cable systems since 1966, we
offer a combination of extra features:
Controlled Cable Traverse - CommScope fiber optic cables are traversed so they coil neatly and permit the
smoothest possible payoff, thus avoiding cable kinking and snagging during payoff in the field.
Water Penetration Testing - Both ends of the cable are cut off and tested to Telcordia and ICEA standards
for water penetration. The one-meter sections are connected to a one-meter column of water. The cable section
should be able to prevent seepage over its length for a 24-hour period.
Certified Test Report - A report of attenuation and length test results is attached to the reel for proof of
performance and to provide a baseline for installer testing in the field.
In addition to the paper copy of the test reports, we also offer WebTrak®, a web program that puts factory cabling
results on-line for all of our fiber optic cables. The WebTrak® program resides on our commscope.com website
for quick access from any computer. For access to the electronic test reports, all the installers need is the 11-digit
serial number printed on the cable jacket and a footage or meter marker for reference. Installers can then enter
this number and pull up the cable’s factory test results from anywhere in the world at any time of the day or night.
CommScope also takes the extra step of spooling cable onto high quality reels. A good, nonwarped reel helps
payout and lessens the chance of the cable rubbing against the reel to cause abrasion of the cable jacket. A solid
reel also prevents painful splinters - something the experienced installer will appreciate.
Cable Types Drop Cables
CommScope Drop Cables
The Efficient Design for Broadband Networks
The design of Drop cables complements the needs often found in the broadband cable plant. Drop cables offer a
compact, flexible and cost-efficient configuration that provides low-loss performance when twelve fibers or less are
needed.
Drop cables feature the tightest loaded and unloaded bend radii in the industry for
optimum flexibility in installation. These cables meet virtually all Telcordia GR-20-CORE
requirements*. The drop cables were designed to meet the S-110-717-2002
“Standard for Optical Fiber Drop Cable”.
The Flat Drop cable design is a small, lightweight cable construction designed for
ease of handling and installation. The costs associated with bonding and grounding
is eliminated with the all-dielectric design while the Toneable design incorporates a 24
AWG copper conductor that is used to locate the cable after it is buried in the field.
Dual ripcords simplify cable access and installation. Both designs are qualified to the
ANSI/ICEA S-110-717-2002 Standard for Optical Fiber Drop Cable and are both
RUS/RDUP: RD Telecommunications Program listed.
Versions include:
Outside plant armored up to 12 fibers
Outside plant dielectric up to 12 fibers
Flat Drop up to 12 fibers
Toneable Flat Drop up to 12 fibers
Drop cables are commonly used to branch from the main cable route to outlying
distribution points.
All drop cables can be pre-installed in conduit.
*GR-20-CORE requirements call for tensile strength of 600 lbs. Drop cables are rated at 300
lbs., which is more than sufficient because of their smaller size, lighter weight and excellent flexibility.
2.1
2.2
Cable Types
Central Tube Cables
CommScope Central Tube An Efficient Alternate to Stranded Loose Tube
System providers striving to reduce costs and increase network efficiency can choose CommScope’s
central tube design for CommScope fiber optic cable.
Central Tube Cables feature a single buffer tube to accommodate higher fiber
counts. Central tube cables save time and money because the single tube design
reduces termination cost. Their smaller diameter makes them pull easier and take up
less valuable conduit space.
Color-coded high-strength binders are applied in a counter-rotating fashion to
separate fibers into easily-traced bundles of 12. The central tube is gel-filled for
moisture protection.
Outside plant versions meet or exceed the Telcordia GR-20-CORE Mechanical and
Environmental requirements. Riser-rated indoor/outdoor versions meet or exceed
the Telcordia GR-409-CORE, GR-20-CORE and ANSI/ICEA 696 Mechanical and
Environmental requirements.
Available versions include:
Outside plant armored up to 48 fibers
Outside plant dielectric up to 48 fibers
All central tube cables can be pre-installed in conduit.
Cable Types
Stranded Loose Tube Cables
CommScope Stranded Loose Tube Traditional Cables with Innovative Design
In situations requiring high fiber counts, stranded loose tube cables offer the capacity and design flexibility required
for high-traffic trunk applications as well as excellent fiber management.
Stranded Loose Tube Cables offer excellent flexibility and the durability
for long distance pulls. Certain stranded loose tube cables can be ordered in
lengths as long as 7.5 miles (12.2 km). Where more arduous conditions prevail
(temperature extremes, higher incident of rodent damage), CommScope offers
stranded loose tube cables with especially rugged combinations of jackets and
armor.
Outside plant versions meet or exceed all Telcordia GR-20-CORE, as well as
ANSI/ICEA 640 requirements. Indoor/outdoor versions meet or exceed all
Telcordia GR- 409-CORE, GR-20-CORE and ANSI/ICEA 696 requirements.
Available versions include:
Outside plant armored and dielectric up to 576 fibers
Outside plant self-supporting armored and
non-armored Figure-8 up to 288 fibers
Outside plant rugged condition (double jacket/single armor)
up to 288 fibers
Outside plant rugged condition (triple jacket/double armor)
up to 288 fibers
Indoor/outdoor riser-rated dielectric up to 288 fibers
Indoor/outdoor plenum-rated dielectric up to 144 fibers
Loose tube cables are best used for high-traffic trunk and distribution.
All loose tube cables can be pre-installed in conduit.
2.3
2.4
Cable Types
ADSS Cables
CommScope’s ADSS Cables Special Purpose Stranded Loose Tube Cables
ADSS (All-Dielectric Self-Supporting) is a loose tube non-metallic fiber optic cable that is designed
to be installed without the assistance of metal strand. An ADSS cable uses aramid yarn and a high tensile
central strength member for support. ADSS cable attaches directly to the pole or tower with the use of special
attachment hardware (see page 2.5).
Special Note
ADSS fiber optic cables are custom designed to fit the maximum span
lengths of your plant. Be sure to have this information available for
your customer service representative when placing orders.
Cable Types
ADSS Cables
Advantages of ADSS Cable
•ADSS cable offers great strength and flexibility for placement on overhead transmission towers or poles
eliminating the need for a support messenger.
•Tension strength capability required for installation in the toughest environmental and electrical conditions
and completely unaffected by electromagnetic fields.
•Single strand or ribbon technologies for ease of mid-span breakout or high fiber count needs.
•ADSS cable offers high tensile strength and can reach spans in excess of two kilometers (6,500 feet).
Making a perfect aerial solution for river or gorge crossings.
•ADSS cable reduces the cost of installation with less manpower and the elimination of metal strand and
lashing.
ADSS Hardware
•ADSS pole hardware (shown at right) is made available
through Tyco and Preformed Line Products.
Construction Methods
•Please reference 7.1 through 7.4 of this manual for installation
instructions.
•CommScope recommends verification of sag and tension for
self-supporting cables. Please call our Technical Resource Center
for recommendations.
2.5
2.6
Cable Types
Hybrids
CommScope Hybrid Cables
Revenue generating units, or RGUs are central to the business model of every broadband service provider and
more than any other cable construction, hybrid cable designs are becoming the choice to enable numerous
outlets for cable television, HDTV, computer networking, multi-line telephone service, security, energy management
systems, and more–all via a single cable run.
Using our unique position as the one cable supplier manufacturing
coax, twisted pair and fiber optic cables under one roof, CommScope
employs advanced engineering technologies by extruding and testing each
component of a hybrid cable congruently.
CommScope offers true hybrid/composite cables featuring subunits
contained within a single jacket. Our constructions offer the additional
protection of an outside jacket compared to designs offered by many vendors
that are merely a bundle of subunits wrapped together with a special tape or
binder thread – frequently called “speed pull”. CommScope hybrid cables
are constructed from subunits carefully selected and performance-verified
individually and as the sum of individual parts.
Special designs can be produced quickly and economically at your request,
using our flexible manufacturing system. In fact, CommScope will help define
the product that best meets your specific needs. Contact any CommScope
sales representative at (800) 982-1708.
(Shown at left, left to right)
Fiber + UTP + Coax Hybrid Cable
Fiber + UTP Hybrid Cable
Fiber + Coax Hybrid Cable
Cable Types
Hybrids
CommScope Hybrid Cables Features and Benefits
Features
Benefits
May contain copper
UTP, coax and fiber optic
subunits individually
jacketed then cabled in a
single bundle under one
smooth surface.
•Great for multiple cable drops, phone/data lines, security systems
and multimedia requirements
•Saves time and installation dollars
•Easier materials management
•Components can be easily separated into individually jacketed points
for easy termination
•Capable of voice transmission, cable location and site powering
•Avails future proofing for the demands of advanced data video and
telecommunications for subscribers
•Less prone to snags and violations of cable bend radius limits
•Enhances the cable’s ruggedness enabling each subunit to better
withstand the rigors of cable installation and remote field applications
Coax cable subunits
•Robust drop or trunk cable components are available in a variety of
braid options to provide protection against moisture, liquids and
gases while boasting excellent mechanical strength and transmission
qualities
Singlemode and/or
multimode fiber optic
cable subunits
•Excellent for transmission of critical audio and video signals with
extraordinary reliability and clarity. No other medium today can
challenge fiber optics in bandwidth, distance and noise immunity
•Available in armored constructions for additional rodent and
environmental protection
•Tight buffered, loose tube or central tube designs offered in
singlemode or multimode optical fiber types and a range of grades
Copper twisted pair
subunits
•Often used in broadband networks for powering nodes and pedestals
•Specify Category 5e rather than Cat 5. The cost differential is small
compared with the quality and performance advantages gained – in cluding the potential for significantly higher speeds and greater capacity
2.7
2.8
Cable Types
Alternative Jacket
Alternative Jacket
CommScope’s Alternative Jacket is a patented polymer blend that utilizes food grade additives including bittering
agents and capsaicinoids to deter squirrels from chewing the jacket. The material is intended to make the act of
cutting their teeth back on cable an unpleasant experience. The combination of bitterness and sensation of heat
from the capsaicinoids have proven to be enough to discourage squirrels from this behavior.
The additives blended into the polymer are temporarily unpleasant but are not harmful to wildlife.
CommScope’s Alternative Jacket Fiber Optic Cable is installed using the same process as standard outside plant
stranded loose tube fiber optic cable.
Handling Precautions
Some people may show sensitivity to the additives in AJ resulting in mild skin reaction. CommScope recommends
the use of gloves while handling and working with Alternative Jacket cables, and thoroughly washing hands with
soap and water after working with the cable. Avoid contact with eyes and take normal precautions including the
use of safety glasses when preparing cable.
- Non-toxic, environmentally friendly
- Unpleasant to taste and smell
- Reduces the amount and intensity of chews
- Standard warranty applies
- Designated by 3 green tracers on the outer jacket
Fiber Features
LightScope ZWP®
The Cable Industry’s Fiber SupplierTM
LightScope ZWP® singlemode fiber optic cable continues a
CommScope tradition of being the leading manufacturer of
innovative and performance-enhancing products for the
communications industry.
CommScope’s LightScope ZWP® fiber optic cable offers Full
Spectrum AdvantageTM transmission capability while being fully
backwards compatible with existing singlemode legacy fiber
optic cable plants. LightScope ZWP® makes available 30% more
usable transmission spectrum, which can be used for return path,
enhanced video services such as video on demand (VOD) or
Dedicated Wavelength ServicesTM for business or other applications.
Features & Benefits
•LightScope ZWP®, zero water peak full spectrum singlemode fiber optic cable, opens up transmission
over the previously unusable wavelength range from 1360nm to 1460nm known as the “Extended Band”
or E-band.
•Enables 16 channel coarse wavelength division multiplexing (CWDM) as a lower cost alternative to dense
wavelength division multiplexing (DWDM) in unamplified portions of hybrid fiber coax (HFC) networks.
•Enables transmission from 1260nm to 1625nm adding 30% more usable spectrum.
•For the communication industry, making use of the full transmission spectrum translates to added capacity
enabling service-rich systems and revenue enhancing growth.
•Fully compatible with legacy standard singlemode fiber optic networks.
•Provides future bandwidth upgradeability.
3.1
3.2
Fiber Features
LightScope ZWP®
Reduced Attenuation
LightScope ZWP cable is designed for use in the wavelengths between1260 nm and 1625 nm, including the formerly off-limit wavelengths in the E-band. LightScope ZWP provides superior attenuation performance throughout
this range of wavelengths, including a lower attenuation performance at 1383 nm than at 1310 nm.
LightScope ZWP - Reduced Water Peak
Standard singlemode fiber has a pronounced attenuation increase at 1383 nm. This region, called the water
peak, is an area within the fiber’s transmission spectrum where light is increasingly
absorbed by the hydroxyl (OH-) ions present within the structure of the glass core.
Hydroxyl ions are the cause of increased
attenuation within the E-band. These ions
are removed during the manufacturing of
LightScope ZWP, thereby reducing attenuation spikes in the E-band and rendering
this portion of the transmission spectrum
usable. The E-band accounts for 30% of
the transmission spectrum available in
silica glass fibers.
LightScope ZWP provides superior low water peak performance in the E-band over
the lifetime of the product. This performance is ensured by a unique ultra-purifying manufacturing process which
virtually eliminates hydroxyl ions in the glass fiber. The resulting decrease in attenuation over the water peak region,
and relatively lower 1400 nm band dispersion (compared with conventional fiber in the 1550 band), results in a
product offering increased transmission spectrum and the economic benefits of less expensive transmission options.
Fiber Features
LightScope ZWP® Specifications
LightScope ZWP Type 8W Singlemode Fiber Specifications
Dispersion-Unshifted, Matched-Clad Singlemode Fiber
ITU-T G.652.D, G.657.A1
Physical Characteristics
Cladding Diameter
125 ± 0.7 µm
Core/Clad Offset
< 0.5 µm
Coating Diameter (uncolored)
245 ± 10 µm
Coating Diameter (colored)
254 ± 7 µm
Coating/Cladding Concentricity Error, maximum
12 µm
Clad Non-Circularity
< 1%
Mechanical Characteristics Prooftest
100 kpsi (.69 Gpa)
Coating Strip Force
0.3 - 2.0 lbf (1.3 - 8.9 N)
Fiber Curl
>4m
Dynamic Fatigue Parameter (nd)
> 18 nd
Macrobend 100 turns @ 50mm mandrel
1550 nm
0.05 dB maximum
Macrobend 1 turn @ 32mm mandrel
1550 nm
0.05 dB maximum
Environmental Characteristics
Temperature Dependence -60°C to +85°C
Temperature Humidity Cycling -10°C to 85°C up to 95% RH
Water Immersion, 23 + 2°C
Heat Aging, 85 + 2°C
*Initial attenuation at 1385 nm shall be no greater than the specified value.
The attenuation shall not exceed 0.35 dB/km at this wavelength during the life of the cable.
< 0.05 dB
< 0.05 dB
< 0.05 dB
< 0.05 dB
3.3
3.4
Fiber Features
CommScope Fiber Specifications - LightScope ZWP
LightScope ZWP Type 8W Singlemode Fiber Specifications
Dispersion-Unshifted, Matched-Clad Singlemode Fiber
ITU-T G.652.D, G.657.A1
Optical Characteristics, Wavelength Specific
Attenuation, Loose Tube Cable
1310 nm
1385 nm
1550 nm
Attenuation, Tight Buffer Cable
1310 nm
1385 nm
1550 nm
Mode Field Diameter
1310 nm
1385 nm
1550 nm
Group Refractive Index
1310 nm
1385 nm
1550 nm
Dispersion
1310 nm
1550 nm
0.34 dB/km
0.31 dB/km
0.22 dB/km
0.50 dB/km
0.50 dB/km
0.50 db/km
9.2 + 0.3 µm
9.6 + 0.6 µm
10.4 + 0.6 µm
1.467
1.468
1.468
3.5 ps/(nm-km) from 1285 to 1330 nm
18 ps/(nm-km)
Optical Characteristics, Wavelength Specific
Attenuation @ 1385 nm
Point Defects
Cutoff Wavelength
Zero Dispersion Wavelength
Zero Dispersion Slope
Polarization Mode Dispersion Link Design Value
Specifications are subject to change without notice.
0.32 dB/km
0.10 dB
< 1260
1302 - 1322 nm
0.090 ps/(km-nm-nm)
< 0.06 ps/sqrt(km)
Fiber Features
Splice Compatibility with other Fibers/Mode Field Diameter- LightScope ZWP®
A Median Mode Field Diameter Produces a Superior Splice
Mode Field Diameter - Optical fiber is composed of two regions - a narrow core surrounded by a
much thicker cladding. In a typical fiber size specification, the diameter of the core is 8.3 µm - the cladding is 125
µm (µm is a micron or 1/1,000,000th of a meter).
In singlemode fiber, about 80% of the light is carried in the core - the remaining 20% is carried in the cladding. The
core and section of the cladding that carries the light is referred to as the mode field.
Mode Field Diameter (MFD) is a critical performance specification
for splicing and connectorization purposes. Matching mode field
diameters minimizes the splicing or connector losses associated with
joining two different sections of fiber. It also minimizes the number
of attempts needed to get a connection to meet the low loss requirements of today’s high capacity systems.
fiber side view
In an ideal world, all fibers would have the exact same MFD. The
reality is that there will be some variance in MFD from fiber to fiber.
However, minimizing this variance will save an operator both time and money. The industry standard for MFD is
9.2 µm ± 0.5 µm, with some manufacturers reducing this to ± 0.4 µm. To provide even better performance,
LightScope ZWP is engineered to produce an MFD or 9.2 µm ± 0.3 µm.
3.5
3.6 Fiber Features
Splice Compatibility With Other Fibers/Core-Cladding Offset LightScope ZWP
A More-Centered Core Keeps Splices on Target
Along with mode field diameter, core/cladding offset is another factor that affects the quality of the splice.
Core/Cladding Offset - All manufacturers strive to build the core as close to the center of thecladding as
possible so that when the fiber is viewed in cross-section, the core and cladding form concentric circles. If the core
is in the exact center of the cladding (the optimal position), the core/cladding offset is zero. A low core/cladding
offset means a cleaner splice because the cores of the fiber align more precisely.
8.3/125 µm fiber with
industry standard
1.0µm max. core offset
8.3/125 µm fiber with
LightScope ZWP
0.5µm max. core offset
Telcordia standards permit a core/cladding
offset of no more than 1 µm. A worst-case
scenario of splicing two 8.3 µm/125 µm fibers
with a 1 µm offset would cause enough splice
loss to force the technician to break and resplice
the fiber. This wastes time and slows the speed
of the installation.
Worst-case scenarios
maximum core/cladding offset
LightScope ZWP fiber optic cables have a core/cladding offset of no more than 0.5 µm. The result is faster, lowerloss splicing, not only with our own cables but to those of other manufacturers for speedier installations and better
system performance.
Fiber Features 3.7
CommScope Fiber Specifications LightScope NZDTM
LightScope NZDTM Type 8T Optical Fiber:
Non-Zero Dispersion Shifted Singlemode Fiber
ITU-T G.655.A,B,C
Physical Characteristics
Cladding Diameter
125 ± 0.7 µm
Core/Clad Offset
< 0.5 µm
Coating Diameter (uncolored)
245 ± 5 µm
Coating Diameter (colored)
256 ± 8 µm
Coating/Cladding Concentricity Error, maximum
12 µm
Clad Non-Circularity
< 1%
Mechanical Characteristics Prooftest
100 kpsi (.69 Gpa)
Coating Strip Force
0.3 - 2.0 lbf (1.3 - 8.9 N)
Fiber Curl
>4m
Dynamic Fatigue Parameter (nd)
> 20 nd
Macrobend 100 turns @ 75mm mandrel
1550 & 1625 nm
0.05 dB maximum
Macrobend 1 turn @ 32mm mandrel
1550 & 1625 nm
0.50 dB maximum
Environmental Characteristics
Temperature Dependence -60°C to +85°C
Temperature Humidity Cycling -10°C to 85°C up to 95% RH
Water Immersion, 23 + 2°C
Heat Aging, 85 + 2°C
*Initial attenuation at 1385 nm shall be no greater than the specified value.
The attenuation shall not exceed 0.35 dB/km at this wavelength during the life of the cable.
< 0.05 dB
< 0.05 dB
< 0.05 dB
< 0.05 dB
3.8
Fiber Features
CommScope Fiber Specifications - LightScope NZDTM
LightScope NZDTM Type 8T Optical Fiber:
Non-Zero Dispersion Shifted Singlemode Fiber
ITU-T G.655.A,B,C
Optical Characteristics, Wavelength Specific
Attenuation, Loose Tube Cable
1310 nm
1550 nm
1625 nm
Attenuation, Tight Buffer Cable
1310 nm
1550 nm
1625 nm
Mode Field Diameter
1310 nm
1550 nm
1625 nm
Group Refractive Index
1310 nm
1550 nm
1625 nm
Dispersion
1310 nm
1550 nm
1625 nm
0.45 dB/km 0.25 dB/km
0.34 dB/km
N/A
N/A
N/A
8.4 + 0.6 µm
8.9 + 0.6 µm
1.471
1.470
1.470
-8 ps/(nm-km) (typical)
2.6 to 6 ps/(nm-km) from 1530 - 1565 nm
4.0 to 8.9 ps/(nm-km) from 1565 - 1925 nm
Optical Characteristics, General
Attenuation @ 1385 nm
Point Defects
Cutoff Wavelength
Dispersion Slope
Polarization Mode Dispersion Link Design Value
Specifications are subject to change without notice.
1.0 dB/km
0.10 dB
< 1260
< 0.05 ps/(km-nm-nm) at 1550 nm
< 0.1 ps/sqrt(km)
Fiber Features
CommScope Fiber Specifications - LightScope NZDTM
Why Dispersion-Shifted Fiber?
Dispersion-shifted fiber is needed when the bit rate and transport distance combination is such that dispersion
begins to degrade system performance. This can occur when bit rates are above 2.5 Gb/s or when transport
distances are over 100 km. Dispersion-shifted fiber, as the name implies, shifts the zero dispersion point from its
location at 1310 nm in standard singlemode fiber (SMF) to above 1450 nm (see chart). More importantly though,
by shifting the dispersion curve it also reduces the dispersion level in the 1550 nm which is the region where Dense
Wavelength Division Multiplexing (DWDM) and optical amplification technology operates. Reducing the dispersion
through the use of dispersion shifted fiber enables a greater reach at the same level of dispersion or improved
system performance at the same reach. The alternative to dispersion-shifted fiber is dispersion compensation.
Dispersion compensation is usually achieved through the use of a long section of highly negative dispersion fiber
that is typically housed in a module and inserted in line with the system. While this is a viable option, it must be
weighed against that additional loss, increased Polarization Mode Dispersion (PMD), and additional components
and cost that dispersion compensation introduces.
LightScope NZDTM is a Non-Zero Dispersion-Shifted (NZD)
fiber designed for use with systems that operate in the 1550
nm region. Some of its key performance capabilities include:
•4x reduction in dispersion levels at 1550 nm relative to
standard SMF
•Reduced dispersion slope resulting in very low
dispersion in both the C and L bands
•Low dispersion coupled with a moderate effective area
provides for excellent Non-Linear Distortion (NLD) performance. Non-linear products such as Four Wave
Mixing (FWM) are kept at levels that are sufficiently low to avoid any significant signal degradation
•A moderate effective area results in very efficient Raman amplification. This can be used as a lower noise
substitute for conventional optical amplification
Overall, LightScope NZD provides equivalent or better transmission characteristics than other NZD fibers,
translating into greater reach, and a lower transmission Bit Error Rate (BER)
3.9
4.1
Storage and Testing
Inspection
Inspecting and Unloading Fiber Optic Cables
Trouble-free unloading begins with letting your CommScope Customer Service Representative know of any special
packaging or delivery requirements (no shipping dock available, call before delivery, etc.). CommScope will make
every reasonable effort to comply with your shipping needs.
When the shipment arrives, make sure the cable types and quantities match the bill
of lading. Contact your CommScope Customer Service Representative if there is a
discrepancy.
Inspect every reel and pallet of material for damage as it is unloaded. Suspect
cable should be set aside for a more detailed inspection before the shipping
documents are signed.
Reels of fiber optic cable are shipped on their rolling edges, not stacked flat on
their sides. Make sure you note the orientation and condition of the reel in your
inspection.
CommScope
makes every
effort to assure
that fiber optic
cables arrive in
the same 100%
ready-to-install
condition as
when they left
the factory
If any cable damage is visible or suspected and if it is decided to accept the shipment, note the damage and the
reel number on ALL copies of the bill of lading.
If the damage is too extensive to accept the shipment, advise the carrier’s driver that the shipment is being refused
because of the damage. Immediately notify CommScope’s Customer Service Department so that arrangements
can be made for a replacement shipment.
Cable performance test results taken at CommScope are provided with each reel. Compare them to your own tests
using the methods outlined on page 4.4.
Storage and Testing
Unloading and Moving Fiber Optic Cable
Fiber optic cable reels are typically delivered on a substantially heavier reel than coaxial cable.
Therefore, they must be loaded and unloaded using a crane, special lift truck or forklift.
Forklifts must pick the reel up with the flat side of the reel facing the driver.
Extend the forks under the entire reel. DO NOT pick the reel up with
the lags facing the driver. Keep all reels upright on their rolling
edges and never lay them flat or stack them.
All reels are marked with an arrow indicating the direction in which the
reel must be rolled. Roll only in the indicated direction.
DO NOT drop reels off the back of the truck onto a stack
of tires, onto the ground or any other surface.
The impact may injure personnel and will damage the cable. Always
use ample personnel to safely unload shipments of cable.
The reel is labeled with handling directions. Consult these directions
if you have any doubt about handling the reel.
Storing Fiber Optic Cable
Fiber optic cable is always stored on the rolling edge and typically
away from the main cable storage area to prevent possible
damage. To prevent reel deterioration during long term storage,
store optical fiber cable in a manner that protects the reel from
the weather.
Cable Handling
4.2
4.3
Storage and Testing
Factory and On-Site Testing
Testing CommScope Fiber Optic Cables
While testing reels of fiber optic cables at delivery is not required, testing prior to, during and after
construction is essential to identify any cable performance degradation caused during installation.
There are four phases in fiber optic cable testing:
1) Visual inspection for shipping damage (see page 4.1),
2) Pre-installation testing, which occurs immediately after cable
delivery,
3) Installation testing, which occurs after the cable is installed or
placed in the plant and at every splice point, and
4) Final acceptance testing, which occurs just prior to activation.
Every reel of
CommScope fiber
optic cable is extensively tested for attenuation, flaws and
continuity and a copy
of the certification
report is attached to
the reel
Pre-Installation Testing
Pre-installation testing typically consists of an OTDR (Optical Time Domain Reflectometer) test performed at 1550
nm. All CommScope fiber optic cables are OTDR-tested prior to shipment and the test report is attached to the
reel. A pre-installation test will verify the characteristics of the cable and check for any shipping damage. The tests
can be jointly conducted by the system operator and the construction group in order to preclude future difficulties
should a cable be damaged during construction.
Installation Testing
Cable should be tested once it has been placed in the plant and prior to splicing to make sure that
there has been no installation damage. Installation testing is usually done with an OTDR. Splice testing
takes place after each splice to insure that a clean, low-loss connection was made. OTDR, local injection detection
and/or profile alignment, can be used alone or in combination for splice testing.
Post Installation - Final Acceptance Testing
The usual post installation testing method is to perform end-to-end OTDR testing. The results should be compared
to the pre-installation test. It is highly recommended that an ongoing testing program be established after the
system is powered up (see page 13.1).
Storage and Testing
OTDE Attenuationi Testing
Attenuation Testing With an OTDR
Attenuation testing with an OTDR (Optical Time Domain Reflectometer) should be performed as part of any preinstallation test regimen. All the fibers in a cable should be tested and the results recorded and
documented.
Attenuation is defined as the loss in optical power as it travels through fiber optic cable and is usually expressed
in decibels per 1,000 meters (dB/km). Attenuation testing can be used to compare actual attenuation data to
the specifications provided by CommScope. Field attenuation characteristics of a reel of fiber optic cable should
be the same as when it was tested at the CommScope factory. Other general attenuation tests include cable reel
acceptance, splice loss verification, and final end-to-end measurements. Signature traces should be made of all
fibers after splicing and connectorization to show the entire cable route. These traces will be invaluable if trouble
develops in the passive cable plant.
OTDRs have several significant advantages over
other test methods. OTDRs are extremely versatile
instruments that can be operated by a single
technician. Through periodic comparison with
the initial signature traces, OTDRs may provide
early warning of a potential catastrophic
failure by indicating points of stress in the cable.
The OTDR operates by transmitting an optical pulse
through the fiber. Signal loss is measured
by charting the reflections of a pulse of light as it is
backscattered by the glass structure or
more strongly reflected by a flaw or break in the
Typical OTDR display
fiber or the end of the cable itself. Distance to the
flaw is measured by the elapsed time between the generation of the pulse and the arrival of the reflected light back
at the OTDR. The result (a linear trace of the fiber displayed as distance from the source [horizontal axis] versus
relative power [vertical axis]) is displayed on a screen or printed out.
Operation of OTDRs vary according to manufacturer. Consult your OTDR documentation for instructions.
4.4
4.5
Storage and Testing
Documentation
System Documentation and Field Test Data
Documentation is essential in the optical fiber plant. While a coaxial installation deals with a single conductor over
a span, an optical fiber installation involves multiple fibers in a cable that may be
significantly longer. If a cable is damaged during installation and not detected by on-going field testing, the
replacement costs can be extremely high.
Documentation
The minimum documentation required for a fiber optic cable network should include the schematic
drawings, splice loss data, end-to-end optical loss measurements and end-to-end OTDR signature traces.
The purpose of this documentation is to provide historical references for
maintenance and emergency restoration. By maintaining this data, the system
operator is assured of a prompt response by the quick identification, location and
repair of any problem that may occur within a cable route.
The ability to
quickly trace
and solve cable
plant problems
depends on the
accuracy of the
installation
documentation
Field Data
Two types of field data should be collected during the installation process.
Calculated data is obtained from cable reel data sheets and splicing logs.
Measured data, such as OTDR data, is obtained from end-to-end cable testing.
This data becomes part of the permanent record for both the customer and
CommScope. This data provides information that accurately characterizes the optical condition of the passive fiber
optic cable plant.
It is essential that any operator of a fiber transmission system maintain adequate
information about that system for maintenance, trouble-shooting and emergency restoration
procedures. By periodically verifying the attenuation loss of the cable system, the cable operator may be able to
avoid future problems.
Installation Safety Issues Industry Organizations
Installation Safety Issues
Construction of underground facilities requires a substantial amount of manpower, tools and equipment.
Underground and aerial construction will expose the manpower, tools and equipment to hazards, dependent upon
field conditions and circumstances.
The Occupational Safety and Health Administration (OSHA) defines a qualified employee as “any worker who
by reason of training and experience has demonstrated his ability to safely perform his duties.” Only a qualified
employee should be assigned duties that could cause harm or potential harm to the construction crew, general
public, cable plant and other utilities. This manual cannot identify the many hazards that exist in the construction
environment, nor can it dictate the caution required with all tools, equipment and field conditions. CommScope
continues this manual with the assumption that the construction personnel performing the work are qualified
employees.
Three sets of national codes and standards apply to the construction of underground facilities. The OSHA Safety
and Health Standards applies to work in telecommunications and utility installations. The National Electric Code
(NEC) applies to building utilization wiring, i.e. inside plant construction. The NEC applies specifically, but not
limited to, plant that is within or on public and private buildings or other structures. The National Electric Safety
Code (NESC), generally applies to outside plant construction.
Municipal, state, county and local codes are often applied to the construction of telecommunication and utility
systems or work that involves their respective properties and right-of-ways. Pole Lease Agreements often stipulate
specific practices related to safety.
These codes, regulations and specified practices should be investigated, interpreted, communicated and observed.
5.1
5.2
Installation Safety Issues
Underground Safety
Underground Safety
Telecommunication construction is typically done within right-of-way dedicated for the routing of other
underground systems – municipal and utility pipes, wires, cables, and conduits.
Damage to any one of these utilities could cause a disruption of services. At worst, it may cause catastrophic harm
to personnel and surrounding property.
It is usually required by law that you contact all operators of these systems prior to the start of any excavation,
including those that are out of the right-of-way (ROW). These system operators will indicate horizontal location of
their plants with a flag or paint mark, called a locate mark or locate. Law usually requires that the subsurface plant
owner perform this duty within a defined time period and ensure that the locate marks are correctly positioned.
The primary intent of the locate mark is to PREVENT damage to conflicting ROW, not to define liability. However,
the recovery of damages resulting from excavation work is generally decided with high consideration given to the
locate marks.
Once the horizontal location of the conflicting ROW has been established, the depth, or ‘vertical’ location of the
ROW must be determined. This is usually done by potholing, or carefully digging a hole until the conflicting ROW
(or its warning tape) is located.
The owner of the real estate should also be contacted prior to excavation. There may be a water sprinkler, closed
circuit television or communication systems buried in or around the ROW. The excavating party should also make
necessary locate marks on their existing plant.
Underground installations typically terminate in a pit or trench that is accessible to the public. Pits and trenches
MUST be guarded by barricades, warning devices and covers.
Installation Basics
Overview
Aerial Installation of CommScope Fiber Optic Cable
Both CommScope dielectric and armored fiber optic cables can be used in aerial installations. Dielectric cables
contain no metal components, which tends to minimize lightning strikes and avoid electrical field crossover
from power lines. Armored cables offer more mechanical protection from rodent attack but must be grounded.
CommScope fiber optic cables come in several styles in both armored and dielectric versions:
Fiber Optic Drop
a compact, flexible and cost-efficient central tube design for 1 to 12 fibers
Central Tube similar design to the drop cables with a higher capacity of up to 48 fibers
Stranded Loose Tube
available in up to 576 fibers
All Dielectric
Self-Support
a stranded loose tube, non-metallic design available with up to 288 fibers
CommScope also offers some of these cable types in indoor/outdoor riser-rated
versions (NEC 770 OFNR) and plenum-rated versions (NEC 770 OFNP) that can
transition from outdoor to indoor without a need for a splice point. Regular OSP
cables must transition or terminate within 50 feet of entering a building.
The two preferred methods for aerial installation are the back-pull/stationary reel
method and the drive-off/moving reel method. Circumstances at the construction
site and equipment/manpower availability will dictate which placement method will
be used.
Indoor/outdoor
cables transition
from OSP to
building without
having to change
cable types
The back-pull/stationary reel method is the usual method of cable placement. The cable is run from the reel up to
the strand, pulled by a block that only travels forward and is held aloft by cable blocks. Excess (slack) loops (see
page 6.4) are then formed. Lashing takes place after the cable is pulled.
The drive-off/moving reel method may take less manpower and save time in cable placement and lash-up. In it,
the cable is attached to the strand and payed-off a reel moving away from it. The cable is lashed as it is being
pulled. Excess (slack) loops (see page 6.4) are made during lashing. Make sure all down guys at corners and dead
ends are installed and tensioned prior to cable placement.
6.1
6.2
Installation Basics
Pulling Tension
Pulling Tension
Pulling tensions for various CommScope OSP fiber optic cables are shown in this chart. Kellems® or
crimp-on grips are used to pull the fiber optic cable. Make sure you use the correct-sized grip for
the cable being pulled. If aramid yarn is part of the cable structure, tie it to the grip to further
distribute the pulling force.
OSP Fiber Optic
Cable Type
Max. Pulling Tension
lbs/newtons
Drop/Flat Drop Dielectric
300/1335
Drop Armored
300/1335
Central Tube Self-Support 607/2700
Central Tube Dielectric 607/2700
Central Tube Armored 607/2700
Loose Tube Dielectric 607/2700
Loose Tube Armored 607/2700
NEVER EXCEED the maximum pulling tension.
Excessive pulling force will cause the cable to permanently
elongate. Elongation may cause the optical fiber to fail by
strain. Good construction techniques and proper tension
monitoring equipment are essential.
Place enough cable blocks along the route to keep cable
sag to a minimum. Excessive sagging will
increase pulling tension. When pulling, do not let the cable
ride over the reel flange as it may scuff or tear the jacket.
Tail loading is the tension in the cable caused by the mass
of the cable on the reel and reel brakes. Tail loading can
be minimized by using little to no braking during the pay-off of the cable from the reel at times, no braking is preferred. Rotating the reel in the direction can also minimize tail loading of pay-off, but be
careful not to let the reel overspin.
Dynamometers are used to measure the dynamic tension in the cable. They allow
continuous review of pulling tension. Sudden increases in pulling tension, caused
by factors such as a cable falling from a block or a cable binding against pole-line
hardware, can be detected immediately.
CommScope’s
flexible
construction
means less
pulling effort
is required
Break-away swivels are used alone or in conjunction with dynamometers to ensure that
the maximum pulling tension is not exceeded. A swivel with a break tension equal to that of the pulling tension of
the cable is placed between the cable puller and pulling grip. Use one break-away swivel for each cable being
pulled.
Installation Basics
Bending Radius
Cables are often routed around corners
during cable placement. A more flexible
cable (one with a smaller bending radius) will
require less pulling tension to get it through
a bend in the route. CommScope fiber optic
cables are designed for maximum flexibility to
ease installation.
NEVER EXCEED the minimum
bending radius. Overbent cable may
deform and damage the fiber inside and can
cause high attenuation.
Bending radius for fiber optic cable is given
as loaded and unloaded. Loaded means
that the cable is under pulling tension and is
being bent simultaneously. Unloaded means
that the cable is under no tension or up to
a residual tension of 30% of its maximum
pulling tension. The unloaded bending
radius is also the radius allowed for storage
purposes.
6.3
Bending Radiius
OSP Fiber Optic Cable
Type/Max. Fiber Count
Min. Bending Radius in/cm
Loaded
Unloaded
3.5
3.5 (9.0)
(9.0)
1.8
1.8 (4.5)
(4.5)
Drop
Drop Dielectric/12
Dielectric/12
6.8
6.8 (17.4)
(17.4)
3.4
3.4 (8.7)
(8.7)
Drop Armored/12
6.4 (16.2)
6.4 (16.2)
Central Tube Armored/24
8.6 (22.0)
Flat
Flat Drop/12
Drop/12
Toneable
Toneable Flat
FlatDrop/12
Drop/12
Drop Armored/12
3.5
3.5 (9.0)
(9.0)
1.8
1.8 (4.5)
(4.5)
3.2 (8.1)
3.2 (8.1)
Central Tube Armored/24
8.6 (22.0)
4.3 (11.0)
Central Tube Armored/48
10.2 (26.0
5.1 (13.0)
Central Tube Dielectric/24
7.9 (20.2)
4.0 (10.1)
9.5 (24.2)
4.7 (12.1)
Dry Loose Tube Armored/60
9.4 (23.9)
4.7 (11.95)
Dry Loose Tube Armored/72
9.8 (24.9)
4.9 (12.43)
9.4 (23.9)
12.2
(31.1)
4.7 (15.57)
(11.95)
6.1
Central Tube Armored/48
10.2 (26.0)
Central Tube Armored/96
11.8 (30.0)
Central Tube Dielectric/24
7.9 (20.2)
Central Tube Dielectric/48
Central Tube Dielectric/48
9.5 (24.2)
Tube
Central
Dry Loose
TubeDielectric/96
Armored/96
11.1 (28.0)
(28.2)
11.0
TubeArmored/144
Armored/72
Dry
Dry Loose
Loose Tube
9.8 (24.9)
13.8
(35.3)
TubeArmored/120
Armored/60
Dry
Dry Loose
Loose Tube
4.3 (11.0)
5.1 (13.0)
Can be
5.9 (15.0)
Can be
4.0 (10.1)
4.7 (12.1)
Can be
5.5 (13.99)
(14.1)
5.5
Can be
4.9 (17.64)
(12.43)
6.9
TubeArmored/216
Armored/96
Dry
Dry Loose
Loose Tube
11.0 (35.3)
(28.0)
13.8
5.5 (17.64)
(13.99)
6.9
TubeArmored/288
Armored/120
Dry
Dry Loose
Loose Tube
12.2 (40.0)
(31.1)
15.7
6.1 (20.02)
(15.57)
7.9
Dry
Loose
Tube Tube
Armored/432
Loose
Armored/144
18.1
13.8 (46.0)
(35.3)
9.0
(23.0)
6.9 (17.64)
Dry
Loose
Tube Tube
Armored/576
Loose
Armored/216
20.6
13.8 (52.4)
(35.3)
10.3
(26.2)
6.9 (17.64)
Dry
Dry Loose
Loose Tube
TubeDielectric/60
Armored/288
8.2 (21.0)
15.7
(40.0)
Loose
Dry Loose
Tube
Dielectric/96
Tube
Armored/576
8.6 (21.8)
18.1
(46.0)
Dry Loose Tube Dielectric/120
9.8 (25.0)
20.6
(52.4)
4.1
(10.5)
7.9 (20.02)
4.3
9.0 (10.9)
(23.0)
Dry Loose Tube Dielectric/60
11.1 (28.2)
5.5 (14.1)
Dry Loose Tube Dielectric/144
Dry Loose Tube Dielectric/72
12.6 (32.2)
6.3 (16.1)
Dry Loose Tube Dielectric/216
8.6 (21.8)
12.6 (32.2)
6.3 (16.1)
Dry Loose Tube Dielectric/288
14.5 (37.0)
7.3 (18.5)
Loose Tube Dielectric/432
16.9 (43.0)
8.4 (21.5)
Loose Tube Dielectric/576
19.5 (49.6)
9.7 (24.8)
Dry Loose Tube Dielectric/288
14.5 (37.0)
7.3 (18.5)
Loose Tube Dielectric/432
16.9 (43.0)
8.4 (21.5)
Loose Tube Dielectric/576
19.5 (49.6)
9.7 (24.8)
Loose
Dry Loose
Tube
Dielectric/72
Tube
Armored/432
Dry Loose Tube Dielectric/96
Dry Loose Tube Dielectric/120
Dry Loose Tube Dielectric/144
Dry Loose Tube Dielectric/216
8.2 (21.0)
9.8 (25.0)
11.1 (28.2)
12.6 (32.2)
12.6 (32.2)
4.9
10.3 (12.5)
(26.2)
4.1 (10.5)
4.3 (10.9)
4.9 (12.5)
5.5 (14.1)
6.3 (16.1)
6.3 (16.1)
6.31 Aerial Installation
Back-Pull/Stationary Reel Passing the Pole
Back-Pull/Stationary Reel - Puller Set-Up and Block Placement
Cable Block/Corner Block Placement
Use a cable block lifter/lay-up stick to place cable blocks on the strand every 30 - 50 feet (9 - 15 meters).
Place corner blocks at all corners greater than 30° in the pole line. NEVER PULL CABLE OVER THE
END ROLLERS OF CORNER BLOCKS. Use the entire set or they will deform the cable. At corners less than
30°, cable blocks can be placed on the strand several feet from and on each side of the pole/line hardware. The
cable blocks should allow the cable to move through the corner without undue bending or drag.
Cable Puller Set-Up is Cable > Grip > Breakaway Swivel > Puller
Attach an appropriate cable grip to each cable. Secure the grip to the cable with tape to keep the
cable from backing out of the grip should the pulling tension be relaxed.
Place a breakaway swivel between the pulling grip and the cable puller. An in-line dynamometer may
be placed there along with the breakaway swivel.
Place the cable puller on the strand and close the puller gates to secure the puller to the strand.
Attach a pulling line to the cable puller. Pull the cable puller along the strand by hand
or by winch. Place cable blocks to support the cable as it is pulled. The cable puller has
an internal brake, which prevents the cable puller from moving backward on the strand
when the pulling tension is released.
Do not overspin the reel. Keep the cable wraps tight.
Remember to
place slack
loops during
the pull
totaling 5%
of the length
of the cable
Aerial Installation
Back-Pull/Stationary Reel Block Placement
Back-Pull/Stationary Reel - Passing the Pole and Power Winching
Passing the Cable Puller at Poles
Pull the cable puller to the pole and release the tension in the pulling line. Pass the cable and the puller across the
pole face and the pole/line hardware, and attach the cable puller back to the strand. Place cable blocks on each
side of the pole.
At corner block locations, pass the cable puller to the opposite side of the pole and route the cables
through the corner block.
Power Winching Methods
Power winching a pull line to install fiber optic cable is a method often used when
the poleline is obstructed or is in extremely rough terrain because the pull line can be
placed without tension concerns. In winching, the pull line is placed in the cable puller
and run along the strand. Cable blocks must be placed at this time. Once the pull line
is run, it is attached to the fiber optic cable.
CommScope’s
long lengths
and flexibility
lend itself to
power winching
Carefully tension the pull line and begin pulling. Adjust the reel brakes to prevent undue pulling tension. Realtime tension monitoring is required as is radio communication between the lineman observing the pull-out and
the winch operator. Intermediate cable handling may be required as the pulling grips approach cable and corner
blocks.
6.32
6.33 Aerial Installation
Back-Pull/Stationary Reel Lashing
Back-Pull/Stationary Reel - Lashing
Excess Cable for Splicing and Future Relocation
Leave enough excess cable at the first and last pole of the pull to facilitate splicing. The cable should be able to
reach the ground, enter a splicing trailer/truck and be placed in an enclosure. If you are unsure of the length, the
rule of thumb is to always leave more, not less. Cap the open cable end to prevent contamination from dirt or
moisture. Coil the cable, being careful not to exceed the minimum bend radius, and tie the loop to the strand away
from the pole.
Excess cable should be pulled out and lashed back to the strand to facilitate splicing or the future relocation of the
pole-line. Normally, an additional 5% of the total cable span is stored during the installation.
Attach the Lashing Wire Clamp
Place the lasher on the strand. Wrap the lashing wire twice around the strand in the
same direction as the twist in the strand and in the lay of the strand. Pass the lashing wire
between the washers of the lashing wire clamp without overlapping the wire. Wrap the
wire around the clamp to the post on the opposite side of the clamp and wrap it twice
around the post. Cut the wire and tuck it between the halves of the lashing wire clamp.
Use appropriate-sized spacers to prevent fiber optic cable from rubbing against the pole
hardware. NOTE: Use double lashing with two or more cables, at street and railroad
crossings.
Place the cable within the lasher. A cable positioner may be arranged ahead of the lasher for extra guidance as the
lasher is pulled toward the reel.
Keep Sag to a Minimum - Use Cable Blocks for as Long as Possible
For safety purposes, keep sag on the cable at a minimum until it enters the lasher. Do not let the
cable sag so low that it can be hit or run over by traffic. Leave the cable blocks in place until the
lasher is close enough to support the cable. As the lasher approaches cable blocks, either remove
them with a cable block lifter or push the cable blocks to the next pole by utilizing a cable block
pusher.
Aerial Installation
Back-Pull/Stationary Reel Passing the Lasher
Back-Pull/Stationary Reel - Passing the Lasher at the Pole
Passing the Lasher at the Pole
Pull the lasher toward the pole to be passed. Attach a lashing wire clamp to the strand as shown on
Aerial Installation (page 6.15). Remove the lasher from the strand and move it across the pole-face to the
strand and cable on the opposite side of the pole.
Put the cable into the lasher. Close the gates to prevent the lasher from being pulled backward along the strand.
Cut the lashing wire from the lasher and secure the lashing wire to the lashing wire clamp. Make sure that the
lashing wire does not loosen from around the cable.
Attach appropriate straps and spacers as needed. At the back end of the lasher, attach a lashing wire
clamp to the strand about to be lashed. Attach the lashing wire to the clamp. Continue lashing as before.
Carefully rotate the cable reel to take up any excess cable slack prior to lashing each section.
Do not lash the cable too tightly. Although fiber optic cables expand far less than coaxial
cables, they must be permitted to contract and expand along the strand or the cable may
buckle and fail. Remember also to leave a small loop for strain relief.
Lashing Fiber and Coaxial Cables Together
Fiber optic cables that are lashed in the same cable bundle as coaxial cables can be routed directly
along the strand when a coaxial expansion loop is encountered. A simple 2 - 4 inch (5 -10 cm) loop will
provide sufficient strain relief.
6.34
6.35 Aerial Installation
Driive-Off/Moving Reel Set-up
Installation - Drive-Off/Moving Reel Set-Up and Lashing
In the drive-off/moving reel method, the cable is attached to the strand and payed-off by moving the reel
away from it. The cable is lashed as it is being pulled. Excess (slack) loops are made during lashing.
Trailer Set-Up • Attach the Lasher, Set-Up Chute and Cable
Pay the cable off the top of the reel rotating toward the rear of the cable trailer. Use minimal reel braking. Attach a
lashing wire clamp to the strand (see page 6.15) 3 - 5 feet (1 to 1.5 meters) from the pole. Place the lasher on the
strand and attach the lashing wire to the lashing wire clamp (page 6.15).
Position the set-up chute in front of the lasher and attach it to the lasher with a block
pusher (or shotgun). Attach the pull line to the set-up chute or lasher. Thread the cable
through the set-up chute and place the cable in the lasher.
Leave enough excess cable at the first and last pole of the pull to reach the ground, enter
a splicing trailer/truck, be spliced and be placed in an enclosure. If in doubt about the
length, leave more rather than less. Cap the open cable end to prevent contamination
from dirt or moisture. Coil the cable, being careful not to exceed the minimum bend
radius, and tie the loop to the strand away from the pole.
Remember to
place slack
loops during
the pull
totaling 5%
of the length
of the cable
The cable should move only through the chute. If the pole-line is offset from the reel, observe the cable closely as it
moves through the chute. Cable reel offset may cause the cable to abrade on the reel flange and the cable in the
chute to bind.
Aerial Installation
Drive-Off/Moving Reel - Passing the Pole
Installation - Drive-Off/Moving Reel - Passing the Pole
Allow a Loop to Relieve Cable Strain
Stop the lasher about 3 feet (1 meter) from the pole.
Allow for a 2 - 4 inch (5 - 10 cm) loop at the pole
hardware for strain relief.
Passing the Pole
Attach a lashing wire clamp to the strand. Disconnect the set-up chute and lasher and pass them across the poleface. Place them on the unlashed strand far enough from the pole to accommodate a small strain relief loop.
Reassemble the set-up chute and lasher.
Close the lasher gates. Cut the lashing wire and secure it to the lashing wire clamp. Make sure that the
lashing wire does not loosen from around the cable.
Attach another lashing wire clamp to the strand on the unlashed side of the pole allowing enough
distance for a strain relief or equipment. Connect the wire from the lasher to the new clamp. Place the cable in the
set-up chute and the lasher.
Rotate the cable reel to take up any excess slack. Continue until the installation is complete.
6.36
6.37 Aerial Installation
Overlashing
Installation - Overlashing Existing Cable
Overlash Cable Placement
Overlashing cables onto existing cable plant is similar to installing cable onto new strand. However,
there are some unique aspects:
Do not tight-lash fiber and coaxial cables.
A sag and tension analysis should be performed to see if the new cable load will
overwhelm the strand.
Use special overlash cable puller blocks and continuously maintain and monitor the
pulling line tension. Overlash cable pullers do not have a strand brake and will be
pulled backward on the span by the tension in the cables being pulled.
CommScope’s
Spanmaster®
software helps
you quickly
calculate sag
and tension
of spans
Use cable blocks designed specifically for overlash applications. Place them onto the cable bundle with a cable
block lifter and lift the cable with a cable lifter. During lashing, remove the cable blocks from the cable bundle with
a cable block lifter. DO NOT PUSH THE CABLE BLOCKS in front of the lasher as that may damage
existing cables.
Remove all straps and spacers from the existing cable bundle during lash-up. New straps and spacers
may be required - check the old ones carefully to see if they need replacing.
SPANMASTER® Software
CommScope offers SpanMaster, software that aids in the calculation of span sag and tension.
SpanMaster is Windows® compatible and is available through your CommScope sales representative or may be
downloaded from our website, www.commscope.com.
Aerial Installation
Vertical Clearances of Above Ground Cables
Vertical Clearance of Wires, Conductors and Cables Above Ground,
Roadway, Rail or Water Surfaces
Nature of surface underneath wire,
conductors or cables
Insulated communication conductors and cables,
messengers, surge protection wires, grounded guys,
underground guys exposed to 0 to 300 neutral
conductors meeting rule 230E1,
supply cables meeting rule 230C1
Feet
Meters
1.Track rails of railroads (except electrified railroads
using overhead trolley conductors)
23.5
7.2
2.Roads, streets and other areas subject to truck traffic
15.5
4.7
3.Driveways, parking lots and alleys
15.5
4.7
4.Other land transversed by vehicles, such as cultivated,
grazing, forest, orchard, etc.
15.5
4.7
5.Spaces and ways subject to pedestrians or restricted traffic
only
9.5
2.9
6.Water areas not suitable for sailboating or where
sailboating is prohibited
14.0
4.0
17.5
25.5
31.5
37.5
5.3
7.8
9.6
11.4
7.Water areas suitable for sailboating, including lakes,
ponds, reservoirs, tidal waters, rivers, streams and canals
with an unobstructed surface area of:
a.
b.
c.
d.
Less than 20 acres
Over 20 to 200 acres
Over 200 to 2000 acres
Over 2000 acres
8.Public or private land water areas posted for rigging or
launching sailboats
learance above ground shall be 5 feet greater
C
than in 7 above, for the type of water areas served
by the launching site.
6.38
7.1
Self-Supporting Cable Installation
Drive Off/Moving Reel
Self-Supporting Cable Installation - Drive-Off/Moving Reel
The drive-off method is the simplest way to place self-supporting central tube cable.
Attach the cable to pole-line hardware at the first pole of the cable run. Leave enough excess cable to
facilitate splicing. The cable should be able to reach the ground, enter a splicing trailer/truck and be
placed in an enclosure. If in doubt about the length, leave more rather than less. Cap the open cable end to
prevent contamination from dirt or moisture. Coil the cable being careful not to exceed the minimum bend radius
and tie the loop to the top of the pole.
Ground and bond the armor at the first pole. The armor is contacted by means of a clamp (sometimes
called ‘shark jaws’) that pierces the jacket to reach the armor.
Cable blocks should be installed at all poles not framed in dead-end hardware configurations.
Pay the cable off the top of the reel and manually place it into the cable block. Continue to pay-off
the cable slowly and uniformly to keep the pulling tension even. Stop-and-go pulling may cause the
cable to ‘bounce’ and damage it at the pole blocks. Do not let the cable reel overspin and let slack
cable spin off the reel. (Brakes will be required.)
Lift the cable from the cable blocks and place it into the suspension clamp once the cable route has
been tensioned as required. Tension the cable wherever there are dead end hardware configurations.
Ground and bond the armor at these locations once the cable is tensioned.
Self-Supporting Cable Installation
Back-pull/Stationary Reel Set-Up
Self-Supporting Cable Installation - Back-Pull/Stationary Reel Set-Up
Since it is difficult to ground self-supporting central tube cable during a back-pull, extra caution must
be taken during installation. This is especially true if the right-of-way is shared with power cables.
FOLLOW EVERY ELECTRICAL SAFETY PRECAUTION, INCLUDING THE USE OF INSULATED
GLOVES.
Trailer Set-Up
The trailer should be positioned in-line with the strand and twice the distance of the set-up chute to the ground from
the chute. This prevents the cable from rubbing on the pole (or reel) or binding on the chute. If the trailer cannot be
positioned there, move the set-up chute and cable trailer to an adjacent pole.
The cable should pay-off the top of the cable reel. The pay-off of the cable from the reel should cause a downward
force at the hitch of the trailer.
Chock the trailer wheels. Adjust the reel brakes as needed. Place protective barriers and cones as needed to
protect pedestrians.
7.2
7.3
Self-Supporting Cable Installation
Back-Pull/Stationary Reel Pulling
Self-Supporting Cable Installation - Back-Pull/Stationary Reel
Pulling Set-Up
Attach the correct-sized cable grip. Then attach a swivel and a pulling line to the grip. Attention should be given to
the tension that is being placed on the cable. There is not a practical method to monitor the tension in the cable
itself.
Cable Block Placement
Use cable blocks designed to be attached directly to the pole hardware. Pull the cable out along the pole line and
lift it into the cable blocks with a cable lifter or by hand from a bucket truck.
DF Cable
Attach the drop wire clamp
DF (flat) cable can be attached to a P, Q, etc... hook using a drop wire
clamp normally specified for telephone wire. Models include:
Senior Industries #SI-0972SB
Thomas & Betts #23-88881
MacLean Power Systems #2PRMS
These designs use a shim to trap the cable in the clamp’s shell, and then
use a wedge to tighten the shim. The weight of the cable produces tension
that tightens the wedge in the shell to secure the cable.
Underground Installation
Overview
Underground Installation of CommScope Fiber Optic Cable
CommScope fiber optic cables for direct burial are always armored, while those intended to run in duct or conduit
may be either armored or dielectric constructions. CommScope offers several types of fiber optic cable designed
specifically for underground installation:
Drop
a compact, flexible and cost-efficient central tube design for 1 to 12 fibers - its small
diameter translates into excellent flexibility
Central Tube similar design to drop cables but with a higher capacity of up to 48 fibers
Stranded
up to 576 fibers - special jacketing options are available including various multiple
Loose Tubejacket/configurations
Static/Vibratory plowing is the most popular method of direct burial. A plow with a special blade slices
through the ground. The cable runs through a tube in the blade and is placed as the plow moves
forward. Since no dirt is displaced, vibratory plowing is much less intrusive than trenching.
Trenching involves digging or plowing a trench, placing the cable in it and then backfilling it. The
trenching depth should be below the frost level for the area.
Boring (directional and conventional) digs or punches a hole in the earth, usually from one trench to
another. It is an excellent method for crossing areas that cannot be plowed (such as paved roads or
railroad tracks) if they cannot be traversed aerially. Cable is then pulled through the hole.
Underground conduit or ductwork allow cable to be pulled through new or existing underground
cableways. The cable may be armored or dielectric. As with aerial installation, careful attention
must be paid to not exceeding the maximum pulling force or the minimum bend radius.
CommScope offers cable pre-installed in conduit. See page 9.1 for details.
8.1
8.2
Underground Installation
Route/Survey Safety
Underground Installation - Route Survey and Safety
Broadband cable construction is typically done within right-of-ways dedicated for the routing of other underground
systems - municipal and utility pipes, wires, cables and conduits. Damage to any one of these utilities could cause a
disruption of services. At worst, it may cause catastrophic harm to you and surround-ing property.
It is usually required by law that you contact all operators of these systems prior to the start of any excavation,
including those that are out of the right-of-way (ROW). These system operators will indicate the horizontal location
of their plants with a flag or paint mark, called a locate mark or locate. Law usually requires that the subsurface
plant owner perform this duty within a defined time period and ensure that the locate marks are correctly
positioned. The primary intent of the locate mark is to PREVENT damage to conflicting ROW, not
to define liability. However, the recovery of damages resulting from excavation work is generally decided with
high consideration given to the locate marks.
Once the horizontal location of the conflicting ROW has been established, the depth, or ‘vertical’
location of the ROW must be determined. This is usually done by pot-holing, or carefully digging a hole
until the conflicting ROW (or its warning tape) is located.
The owner of the real estate should also be contacted prior to excavation. There may be water sprinkler, closed
circuit television or communication systems buried in or around the ROW. The excavating party should also make
necessary locate marks on their existing plant.
Open Trenches and Pits
Underground installations typically terminate in a pit or trench that is accessible to the public. Pits and trenches
MUST be guarded by barricades, warning devices and covers.
Underground Installation
Static Plowing
Underground Installation - Static Plowing
Static plowing is the preferred method for installing fiber optic cable or conduit. A tractor moves slowly forward as
the blade splits the earth and places the cable at the required depth. Because terrain and soil types vary, contact
your plow manufacturer for their equipment recommendation. We strongly recommend a professionally engineered
single or double feed tube plow blade with a tube at least 0.5 inch (1.3 cm) larger than the largest cable size and
a radius of 12 inches (30 cm) or larger for >144 fiber cables. At a minimum, an operator and a helper/feeder
are needed for a plowing installation. Pulling fiber behind plowshares using a pulling chain or ‘bullet’ is not
recommended.
Local regulations may require (and CommScope
strongly recommends) that warning tape be
plowed in with the cable. Most plow manufacturers
make plow blades that bury cable and tape at the
same time.
Dig a trench deep enough and at least twice the length
of the plow blade/chute for the plow blade to enter it
comfortably. A similar trench should be dug at the other
end of the installation. The cable may pay-off from the
front of the tractor or from a stationary cable reel.
In the tractor method, make sure the reel is not run into objects that may damage the cable. Pay the
cable over the top of the reel. Do not use reel brakes.
Cap or tape the cable end. Remove the back plate from the blade and inspect the feed tube for
burrs, rough surfaces and sharp edges. Clean out any dirt or rocks. Make sure the plow does not
exceed the loaded minimum bend radius of the cable. Carefully place the cable in the feeder tube.
Reattach the back plate.
Carefully pull enough cable through the blade to allow for splicing and storage. Have someone hold
the cable end to keep it from being pulled as the tractor initially moves forward.
8.3
8.4
Underground Installation
Vibratory Plowing
Underground Installation - Vibratory Plowing
While vibratory plowing is not the preferred method for fiber optic cable installation, it can offer substantial productivity gains over other direct burial methods. A tractor (usually smaller than that used in static plowing) moves
slowly forward as a vibrating blade splits the earth and places the cable at the required depth. Because terrain and
soil types vary, contact your plow manufacturer for their equipment recommendation. We strongly recommend a
professionally engineered single or double feed tube plow blade with a tube at least 0.5 inch (1.3 cm) larger than
the largest cable size and a radius of 12 inches (30 cm) or larger for > 144 fiber cables. At minimum, an operator and a helper/feeder are needed for a plowing installation. Local regulations may require (and CommScope
strongly recommends) that warning tape be plowed in with the cable. Most plow manufacturers make plow blades
that bury cable and tape at the same time.
Dig a trench deep enough and at least twice the length of the
plow blade/chute for the plow blade to enter it comfortably. A
similar trench should be dug at the other end of the installation.
Make sure the reel will not run into objects that may damage the
cable. Pay-off the cable over the top of the reel. Do not use reel
brakes.
An alternate method is to use a moving trailer to pay-off the cable on
the surface between the two trenches. Use safety cones to mark and
protect the cable from pedestrian and vehicle traffic. The moving tractor then picks up and passes the cable over the top of the tractor, using a combination of chutes and guides to get
the cable to the plow blade.
Remove the back plate from the blade and inspect the feed tube for burrs, rough surfaces and sharp edges. Clean
out any dirt or rocks. Cap or tape the cable end. Carefully place the cable in the feeder tube. Reattach the back
plate.
Carefully pull enough cable through the blade to allow for splicing and storage. Have someone hold the cable end
to keep it from being pulled as the tractor initially moves forward. Start the vibrator after forward movement begins.
Have the blade in solid contact with the earth before applying full RPM.
•Do not vibrate in place for more than 30 seconds.
•Do not raise the blade unless the tractor is in motion.
•Do not back up with the cable in the blade.
•Do not rotate the blade more than the manufacturer allows.
Underground Installation
Rip and Plow/Plow Movement
Underground Installation - Rip and Plow/Plow Movement
Rip and Plow (Using Two Tractors)
If you anticipate obstructions (like roots) along the installation path, you may want to consider a rip
and plow installation. In rip and plow, a lead tractor rips the ground by pulling a plow without cable
several hundred yards/meters ahead of the tractor with the cable. The first tractor clears the route
and permits the second tractor to work more efficiently.
Handling Obstructions
If obstructions (tree roots, large rocks, etc.) are encountered, disengage the transmission, turn the
engine off and then disengage the clutch. NEVER BACK THE PLOW WITH CABLE IN THE FEED
TUBE. This will damage the cable and pack dirt into the feed tube.
Carefully dig a pit behind the blade. REMOVE THE CABLE FIRST, then remove the obstruction. Replace the cable
and proceed with the installation.
Turning
Gentle turns can be made over a distance of 5 - 8 feet (1.5 - 2.4 meters). Never turn the blade unless
the tractor is moving forward. Some manufacturers make steerable blades.
Lifting the Blade
If ABSOLUTELY necessary (for instance, avoiding a buried utility line), the blade can be gradually raised at a rate of
8 inches (20 cm) over a 5 foot (1.5 meter) run. Lower the blade at the same rate once the underground hazard has
been passed. Do not raise the blade to ground level with cable in the feed tube.
8.5
8.6
Underground Installation
Trenching
Trenching Installations
Trenching is accomplished with specialized trenching tractors which cut the trench and remove the soil in a single
action. A trench can be used to place multiple cables over long or short distances. Detailed equipment operation
and excavation procedures are specified by the construction equipment manufacturer.
All bores and crossings should be installed prior to the start of the trenching process.
Excavate the trench to the desired depth. Remove all rocks and large stones from the bottom of the
trench to prevent damage to the cable. Push some clean fill into the trench or backfill with sand (to cushion the
cable), as it is installed in the trench.
Supplemental trenches should be made to all offset enclosure locations. Trench intersections should
be excavated to provide adequate space to make sweeping bends in the cable/conduit.
Place the cable trailers or cable reels in line with the trench to prevent any
unnecessary bending of the cable. Pay the cable off the bottom of the
reel.
When routing cables to enclosure locations, leave adequate cable
lengths for splicing and storage. Remember to distribute 5% of the total
length of the cable at these locations throughout the installation.
Monitor the bending radius of the cable when going around corners and upward at enclosure locations.
Cap the cable as needed to prevent contamination from dirt and moisture.
Place warning tape above the cable during the back-fill process.
Fill the trench with sand/loose dirt and compact it as required. Tamp or flood the trench to provide compaction that
will prevent the trench from receding.
Underground Installation
Boring
Boring Installations
Conventional Bores
Mechanical boring machines may be utilized to push a drill stem to make an adequate cable passage.
Pneumatically driven pistons may be used as well. Conduit should be placed to support the tunnel
wall and allow cable placement.
Directional Bores
Directional boring is accomplished by using a steerable drill stem. The depth and
direction of the boring can be controlled by the equipment operator. Very long bore
lengths can be accomplished by using directional boring devices.
Subsurface crossings are generally accomplished by digging a trench on each
side of the crossing to allow the guiding and retrieval of the drill stem. Detailed
equipment operation and excavation procedures are specified by the construction
equipment manufacturer.
ConQuest®
cable-in-conduit
is an excellent
system for
installing cable
in bores
Generally, try to keep the bore as straight as possible. The hole may be enlarged by using reamers.
Conduit should be installed at strategic locations (i.e. street crossings).
After the bore is complete, attach the fiber optic cable to the drill stem with the appropriate cable
grip and swivel. Pull the drill stem/cable through the bore. Longer pulls will require tension monitoring.
8.7
8.8
Underground Installation
Fiber Cable in Conduit
Installing Fiber Optic Cable in Conduit
Cable can be pulled in new or existing ductwork. New conduit should be installed in as straight a path as
possible - undulations in the conduit system increase pulling tensions due to sidewall pressure. Existing conduit
systems generally require some maintenance prior to placing cables into the conduit. Always clean the route prior
to installation. Use a rodding machine to remove unwanted debris and water from the conduit.
A cable route survey will dictate the cable placement scheme that should account for the difficulty
of the pull, manpower and equipment availability.
The curve radius in the conduit systems should be large enough to prevent excessive pulling tension due to sidewall
friction. The use of pulling lubricants (such as CommScope’s WHUPP!TM) is recommended to reduce friction and
pulling tension. Very small radius bends may prevent even a cable as flexible as CommScope fiber optic from being
successfully pulled.
Blowing/Jetting Fiber Optic Cable
This process uses a combination of air pressure and a small drive to push fiber optic cable through a
conduit. It is most effective when placing a single cable. Since the cable is not pulled, pulling tension
is not a concern.
Position the reel so the pay-off is from the top and is in as straight a line as possible with the entrance to the
conduit. A small caterpillar drive pushes 150 - 200 feet (45 - 60 meters) of cable into the conduit. Air is then
forced into the conduit and the jetting action helps propel the cable with minimum effort.
With this method, a flexible cable like dielectric Central Tube can be pushed through several 90° sweeps over a
1,500 foot (450 meter) distance of 2 inch (5 cm) rigid PVC conduit.
Underground Installation
Pulling in Stages/Walking the Reel Over
Long Pulls Through Conduit Pulling in Stages to Intermediate Locations
If capstans or other mechanical devices are not available or practical to assist the pull, you can reduce
the overall tension by pulling the cable in stages to intermediate locations.
Underground Installation
Locate the midway point of the pull. While monitoring the tension, pull the cable from the mid-point to an intermediate vault or manhole. Pay the cable up to the surface.
Set up two traffic cones about 10 - 15
paces apart (more for larger cables).
Loosely weave the cable around the
cones in a figure-8 pattern. Large relaxed loops will help you avoid tangling
the cable.
Walking Over the Figure-8
Once you’ve stopped pulling, ‘walk’ the figure-8 over.
Be careful - a figure-8 may weigh several hundred
pounds.
The cable end should now be at the top of the figure-8. Prepare the cable end for pulling toward the
next intermediate location or the end of the pull.
When you resume the pull, the cable will pay off the
top of the figure-8. (The cable end moves to the top of
the pile.)
8.9
9.1ConQuest® Installation
Midpoint Pulls/Setup
Long Pulls Through Conduit - Mid-Point Pulling Technique
CommScope fiber optic cables can be ordered in lengths of up to 7.5 miles (12.2 km) and can be installed in
one continuous run. However, even a typical installation of 3 - 5 miles (4.8 - 8.0 km) offers installation challenges
because of the accumulation in pulling tension along such a long route. A midpoint cable pull is a proven method
for installing long lengths of fiber optic cable.
Mid-point Cable Pull
Locate the midway point of the pull. While monitoring the tension, pull the cable from the mid-point to the end of
one direction. The pull may be assisted at an intermediate vault by a capstan or a craftsman.
Prepare to figure-8 the remaining cable. Set up two traffic cones about 10 - 15 paces apart (more for larger
cables). Pay the cable off the top of the reel and loosely weave it around the cones in a figure-8 pattern. Large
relaxed loops will help you avoid tangling the cable. Continue to figure-8 the cable until the remainder of the reel
is payed off. Remove the cones.
Prepare the cable end in your hand for pulling toward the other end of the installation. When you resume the pull,
the cable will pay off the top of the figure-8.
Fiber Splicing
Fiber Preparation
Splicing Fiber Optic Cables - Fiber Preparation
Trim the Buffer Tube
The buffer tube must be carefully trimmed to reveal the fibers. Use a buffer tube cutter to score the buffer tube in
intervals of 12 - 16 inches (30 - 40 cm). Flex the buffer tube back and forth until it snaps, then slide the tube off the
fibers. The splice enclosure instruction will tell you how far back to remove
the buffer tubes.
Fiber Stripping
The exposed fiber can now be stripped. CommScope fiber optic cables use a 125 µm singlemode fiber
coated to an industry standard 250 µm. A fiber stripping tool will cleanly remove the outer coating.
Do not try to remove any more than 2 inches (5 cm) at one time.
Once a fiber is stripped, it needs to be cleaned with 99% isopropyl alcohol and a lint-free cloth to remove the
coating residue. Keep handling of bare fibers to a minimum. Once cleaned, cleave and splice the fiber as soon as
possible in order to reduce the fiber’s contact with airborne contaminants.
Fiber Cleaving
Cleave the fiber end using a quality fiber cleaver. The cleave should be clean (devoid of chips and lips)
and be within 1° of perpendicular. Try to leave as little bare, uncoated fiber as possible (no more than
1/2 inch [1.25 cm]). Some fusion splicers come with their own cleavers attached. Smaller hand-held
cleavers (called beaver tail cleavers) are not recommended for precision cleaves.
10.1
10.2
Fiber Splicing
Fusion Splicing
Splicing Fiber Optic Cables - Fusion Splicing
Fusion Splicers
There are several brands of fusion splicers available. Most integrate features such as:
•a fusion heat source, usually an electric arc
•V-groove clamps for holding the fibers
•a way of positioning the fibers relative to themselves and the heat source
•a way of viewing the fibers (microscope, display screen) so they can be accurately positioned
Procedures will vary depending on the fusion splicer used. The older models require you to manually match up the
outer diameters of the cleaned fibers before fusing them. More sophisticated ones offer features that automatically
align the fiber cores for the lowest loss splices.
LID (Local Injection and Detection)
Some splicers come equipped with LID in which the fibers to be fused are coiled around a small post
so that light can actually be ‘injected’ through the fiber coating. The light crosses through the alignment
point and is measured on the output side. The fibers are then manually or automatically positioned
until the most light is passing through the aligned fibers. LID systems also monitors the fibers
as they are being fused and shut off the arc when the process shows the lowest splice loss.
PAS (Profile Alignment System)
Splicers equipped with PAS project an image that allows you to view the fiber cores and manually or
automatically bring them into alignment.
Splice Protection
CommScope recommends that the spliced fibers be mechanically reinforced. A heat-shrink sleeve
is placed over the fiber prior to splicing. Once the splice is completed, the sleeve is placed over
the splice and shrunk. There are other methods such as crimpable sleeves, splints and sealants; experience will
show which work best for your application.
Emergency Restoration11.1
Trouble Shooting
Emergency Restoration - Troubleshooting the Problem
There are several reasons for all or any part of a system to ‘go dark.’ The reason may be obvious, such as a falling
tree shearing a span. More often than not, the reasons may not be that apparent. The first step in restoration is to
determine exactly what and where the problem is located. The methodical approach described below is the wisest
way to determine the cause of the outage. All records of installation parameters should be easily available:
Check the Transmitter - Measure the transmitter output at the output connector with an optical
power meter. Check the received power to that recorded at installation.
Check Patchcords at the Transmitter End - Patchcords, connectors and sleeves may be damaged
or defective. Replace suspect patchcords with known good ones and measure the output power
compared to installed values.
Check Patchcords at the Receiver End - Repeat the process above at the far end of the system.
Replace suspect patchcords with known good ones and measure the output power compared to
installed values. If the power is within prescribed limits, the problem is in the receiver.
Check the Cable Plant - This can be done from either end of the system with an OTDR. Compare
the OTDR trace with the as-built documentation. This will often show you to within a few yards
where the problem might be.
Unfortunately, many problems turn out to be a catastrophic failure of the cable. Common causes
include rodent damage, lightning strikes, trees falling on the cable, traffic accidents, gunshots or
other vandalism. Mechanical causes could be freezing water in conduit, failed splices or environmental
damage within a splice closure. In many cases, a short span of cable may need to be replaced quickly
to restore service.
11.2
Emergency Restoration
Materials
Emergency Restoration - Material Checklist
Action can be taken once the location and nature of the problem have been determined. It may be
possible to transfer the signal to an undamaged dark fiber within the cable. However, you should be
prepared to do a full on-site restoration.
If the problem is with a downed pole placed on a utility ROW, make sure the ROW owner is alerted to the
problem. It is important to have an agreement with the ROW owner that gives a high priority to the repair of the
poles you share.
Preparedness is the Key to Quick Restoration
Prior to the emergency, you should have designated a trained response team of fiber technicians
(usually three in number) as well as a secondary technician team. A current notification list should be
made available to designated personnel. Unannounced practice sessions will help with proficiency.
The fiber technicians should have lock-and-key access to an emergency restoration kit. A complete list of kit
materials should be displayed at the storage site. The kits should be inventoried quarterly. Any missing or out-ofdate materials should be replaced IMMEDIATELY. While kits can be purchased, they can be assembled with the
following items:
Cable components Splice trays Splice closures About 300 ft/100 of prepped fiber cable 2x mechanical splices as fibers in the cable System documentation
City/county map with receiver/splice locations clearly noted ‘Hot fibers’ list with routing documentation
Master maintenance/restoration log
with as-built or repaired fiber data
Two Tool/Supply Kits With:
Isopropyl alcohol packs
Gel remover
Vinyl tape
Mechanical stripping tool
Book of numbers
Lint-Free wipes
Pliers
Precision fiber cleaver
Needlenose pliers
Wrenches
Screwdriver
Cable sheath knife
Hook blade knife
Cable ties
Snips
Emergency Restoration
Aerial Restoration
Emergency Restoration - Aerial Installations
Pull in Excess Cable from the Slack Loop
Locate the nearest excess/slack loop on the line. Unlash the cable from the span to the excess loop,
being careful not to let the cable sag into traffic (or other areas where it could be damaged) and not
to let the cable bend past its loaded bend radius.
Unlash the cable on the other side of the break to free enough cable to reach the ground.
While emergency splicing can be performed on the pole, it is easier to do it in a splicing van or tent.
If slack loops are not available to you, patch the cable with the 300 ft (100 m) of prepared cable from
your emergency restoration kit.
Splice With Mechanical Splices
Cut away the damaged ends of the cable. Strip away the jacket and prepare the cable per the instruction with your
emergency splice enclosure. Your emergency restoration kit should contain splice enclosures and trays adapted
for mechanical splices. Prepare the fiber ends for splicing, noting any changes in technique mentioned in the
instructions for the mechanical splices. If at all possible, loop the cable and suspend it from the pole out of harm’s
way.
Mark and Protect the Cable
For emergency purposes, or in cases where the pole line has been damaged, it is permissible to leave
the cable on the ground out of the way of vehicle or foot traffic. Make sure the area is clearly marked
with cones or tape. Restore the pole line as soon as possible. If needed, reinstall a new span of cable.
11.3
11.4
Emergency Restoration
Underground Restoration
Emergency Restoration - Underground Installations
Direct Buried Installations
From the site of the intrusion, dig back in both directions to where the cable has not been disturbed.
Place a manhole or vault at this point. Free up enough cable for handling and splicing purposes by
CAREFULLY digging around the undisturbed cable. When moving the cable, do not let the cable bend
exceed its loaded bend radius. Use the 300 ft (100 m) of prepared cable from your emergency restoration
kit to connect the broken cable.
Conduit and Ductwork Installations
Locate the nearest excess/slack loops on both sides of the break. Pull enough cable from both directions to
accommodate splicing. Place a manhole or vault at this point. If slack loops are not available to you, patch the
cable with the 300 ft (100 m) of prepared cable from your emergency restoration kit.
Splice with Mechanical Splices
Cut away the damaged ends of the cable. Strip away the jacket and prepare the cable per the instructions with
your emergency splice closures. Your emergency restoration kit should contain splice closures and trays adapted
for mechanical splices. Prepare the fiber ends for splicing (see pages 9.1 to 9.3), noting any changes in technique
mentioned in the instructions for the mechanical splices.
Mark and Protect the Cable
For emergency purposes, it is permissible to leave the cable on the ground out of the way of vehicle
or foot traffic. Make sure the area is clearly marked with cones or tape. If needed, reinstall a new
span of cable as soon as possible.
Midsheath Entry
Overview
Midsheath Entry of Fiber Optic Cables Preparation and Jacket Removal
Some installations require that you ‘branch off’ some of the fibers in a cable between points of
termination. This is called a branch splice. To access fibers along a span, use a midsheath entry procedure.
Determine Choke Points/Cut the Jacket
For midsheath entry, first determine the amount of jacket to remove - typically, this will be between 3
and 6 yards (2.8 and 5.1 meters). The amount may vary depending on the splice enclosure to be used;
check the enclosure instructions.
Measure and mark the cable at the ends of the proposed entry points with two turns of vinyl tape.
These are called the choke points. Using a hook blade knife, CAREFULLY make a ring cut through the
jacket at the choke points. In a dielectric cable, E-glass yarn will be the only protection for the buffer
tubes. Therefore, take extreme care not to nick or cut the buffer tube(s).
Remove the Jacket
Free the ripcord by carefully notching the jacket about 6 inches (15 cm) from one choke point. Cut the
ripcord at the choke point. Pull the ripcord through the notch and wrap it around the shaft of a
screwdriver. Using the screwdriver as a handle, pull the ripcord to the other choke point. Carefully
remove the jacket. Cut off the excess ripcord with scissors.
12.1
12.2
Midsheath Entry
Fiber Preparation
Midsheath Entry of Fiber Optic Cables - Buffer Tube Entry
Remove Filler Tubes
Filler tubes have no fibers in them and should be cut at the choke points and removed. Be careful not
to mistake an active white buffer tube for a filler tube; the white tube is located between the slate
and red tubes.
Trim the Central Member and Anchor the Cable in the Enclosure
Use diagonal side cutters to trim the central support member at each choke point to the length specified by the
enclosure manufacturer. Some enclosures require that the central member be stripped of its coating. The central
member will be used to secure the cable in the enclosure. Anchor the cable according to enclosure instructions.
Cut the Tubes and Fibers
In stranded loose tube cables with live fibers within the tube being cut, slit the buffer tube carefully removing the
buffer tube material. Separate the live fibers from the fibers to be cut, and prepare the fibers for splicing as detailed
below.
In stranded loose tube cables in which the entire tube can be cut, cut the buffer tubes and fibers midway between
the choke points. To access the fibers, use a buffer tube cutter to score the buffer tube at intervals of 12 - 16
inches (30 - 40 cm). Flex the buffer tube back and forth until it snaps, then slide the tube off the fibers. The splice
enclosure instructions will tell you how far back to remove the buffer tubes.
In central tube and drop cables, use a buffer tube slitter to open and remove the tube without cutting the fibers.
Once the tube is removed, cut the fibers you intend to break out.
Clean the Fibers/Prepare for Splicing
After the buffer tube has been removed, clean the fibers with 99% isopropyl alcohol. Prepare the
fibers for splicing (see pages 10.1 and 10.2). You will probably be using some type of branch splice enclosure to
accommodate another cable. Prepare the second (branch) cable for termination and its fibers
for splicing.
Plant Maintenance
Overview
Fiber Plant Maintenance
CommScope fiber optic cable actually requires very little maintenance once installed. However, periodic inspection
may reveal small problems that can be corrected before they become large ones.
Maintenance Testing
It is recommended that all the cable in your system be tested with an OTDR at least once every two years.
A good practice would be to test every time you take the transmitter down for maintenance. Comparing these test
results with the final inspection tests permit you to identify and correct gradual losses in performance before they
become the cause for an outage.
Aerial Trunk and Distribution Cable
Worn or broken lashing wire can create serious performance problems, such as wind-caused deformation which
can impact the performance of the cable. Loose lashing can also be the cause of jacket abrasion over long lengths
of cable which can cause water to migrate through cracks in the jacket and lead to mechanical breakdown. If this
sort of damage is detected, CommScope recommends that the entire span be replaced.
Underground Trunk and Distribution Cable
Inspect cable where possible in vaults and manholes. Check the plant periodically with an OTDR to see if there is
any sign of degraded performance. Replace any damaged cable.
13.1
14.1 Appendix
OSHA Standards
Occupational Safety And Health Administration (OSHA) Standards
OSHA Standards were established in 1970 to help ensure workplace safety. The Standards are federal regulations
that are intended to enable employees to recognize, understand and control hazards in the workplace. Standards
have been established for general industry while some sections of the Standards are dedicated to specific industries
such as telecommunications.
The general applicable OSHA Standards are found in:
Title 29 CFR Parts 1901.1 to 1910.399 General Industry, Part 1926 Safety and Health Regulations for
Construction.
Most relevant is Title 29 CFR Part 1910 Occupational Safety and Health Standards
Copies of OSHA standards can be obtained from:
US Department of Labor
OSHA Publications
PO Box 37535
Washington, DC 20013-7535
(202) 693-1888
(202) 693-2498 fax
website: www.osha.gov
Appendix 14.2
NEC Standards
National Electric Code (NEC) Standards
The NEC typically identifies the construction techniques and materials necessary in building wiring require-ments,
i.e., inside plant construction, of fiber optic, coaxial cable, or twisted pair systems. The NEC has been developed
by the National Fire Protection Association’s (NFPA’s) National Electric Code committee. Committee members are
professionals from the electrical industry. The NEC addresses safety from fire and electrocution. The NEC has been
adopted by the American National Standards Institute (ANSI).
Copies of NEC standards can be obtained from:
National Fire Protection Association
1 Batterymarch Park/P.O. Box 9146
Quincy, MA 02269-3555
(800) 344-3555
website: www.nfpa.org
14.3 Appendix
OSHA Standards
National Electric Safety Code (NESC) Standards
The NESC covers supply and communication cables and equipment in underground buried facilities. The
rules also cover the associated structural arrangements and the extension of such facilities into buildings.
The NESC typically identifies the construction techniques and materials necessary in outside plant
construction of electric supply or communication cable systems. The NESC is an American National
Standard that has been written by a group of professionals that are concerned about the Standard’s scope
and provisions. The NESC has been adopted by the American National Standards Institute (ANSI). All
references to the NESC in this manual are from the 2007 edition.
Special attention should be given to NESC Part 3 Safety Rules for the Installation and Maintenance of
Underground Electric Supply and Communication Lines.
Copies of NESC standards can be obtained from:
IEEE Service Center
445 Hoes Lane/P.O. Box 1331
Piscataway, NJ 08855-1331
(800) 678-4333
website: www.ieee.org
Appendix 14.4
Equipment/Blocks
Equipment/Blocks
Multiple Cable Block
Used to support multiple
cables in independent rollers.
Multiple cable blocks make a
cable positioner unnecessary
when lashing multiple cables.
Single Roller Block
Typically used to support a single
cable prior to lashing and may
be used when cables are
lashed directly to strand or in
overlash applications. In new
strand situations, single roller
blocks may be locked onto
the strand. In over-lash
applications, this block
should not be pushed in
front of the lasher.
Pole Mount
Cable Block
Used to install selfsupport cable and is
attached to the pole
hardware to support
the cable as it is
pulled out.
Economy Block
Used to support a single
cable prior to lashing and,
depending on the actual
block, may be used when
cables are lashed directly
to strand or in overlash
applications.
NOTE: Take care that cable slack does not exceed the minimum bend radius over blocks.
14.5 Appendix
Equipment/Dynamometers, Grips and Swivels
Equipment/Pulling Grips and Devices
Dynamometer
Used to monitor the
pulling tension applied
to fiber optic cables.
Breakaway Swivel
Used to prevent excessive
pulling tension. It is designed
to break should it exceed a
pre-set tension limit.
Kellems® Grip
This reusable grip is woven from
strands of stainless steel, acts like
‘Chinese finger cuffs’
and compresses upon
being relaxed. It provides
an evenly distributed
hold on the jacket of
the cable.
Appendix
Equipment/Blocks, Chutes and Brackets
Equipment/Blocks, Chutes and Brackets
90° Corner Block
Used to route cables through inside or outside corners up to
90°. It minimizes drag on the cable in corners and ensures that
the minimum bend radius of the cable is not exceeded. Requires
specialized mounting hardware depending on the specific use of
the equipment.
45° Corner Block
Used to route cables through inside or outside corners up to 45°.
It minimizes drag on the cable in corners and ensures that the
minimum bend radius of the cable is not exceeded. 45° corner
blocks should be used as a set-up chute to guide cables from
the cable trailer or a reel stand. Requires specialized mounting
hardware depending on the specific use of the equipment.
Set-Up Chute
A set-up chute is used
to guide cables from
the cable trailer or reel
stand. This equipment
requires specialized
mounting hardware
depending on the
specific use of the
equipment.
Set-Up Bracket
This bracket is used to
support 45° and 90°
corner blocks or set-up
chutes at mid-span.
14.6
14.7Appendix
Equipment/Lashers, Pullers, Positioners and Guides
Equipment/Lashers, Pullers, Positioners and Guides
Cable Lasher
Used to lash cable directly
to installed strand or cable
bundles. Lashers are somewhat specific to cable and
strand size - improper lasher
size or adjustment may
damage cables.
Multiple Cable Puller
Allows multiple cables to be
pulled into place when
lashing cables directly to
strand. It’s equipped with
a strand brake to prevent
sagging of cables as the pulling
tension is released. Allows pulled
cables to independently swivel.
Overlash Cable Puller
Allows multiple cables to be
pulled into place in overlash applications. Allows
pulled cables to independently swivel.
Cable Block Pusher
(or Shotgun or Shuttle)
Used to push equipment ahead of a
pulled lasher.
Cable Positioner
(or Magic Box)
Pushed in front of a
lasher by a cable
block pusher to
uniformly position
multiple cables that
are being lashed.
Cable Guide
Used to guide the cable
into the lasher in drive-off
applications. Can be
used for new strand or
overlash applications.
The guide may be pushed
in front of the lasher with a
cable block pusher, pulled in
front of the lasher or physically
attached to the lasher, dependent on the cable
guide type.
Appendix14.8
Equipment/Lifting Tools land Brakes
Equipment/Lifting Tools and Brakes
Lay-Up Stick
A fiberglass stick used to lift cable blocks and cables into place utilizing appropriate lay-up stick heads.
Cable Lifter (or Lay-up Stick Head)
Used in conjunction with a lay-up stick to lift cables into place. The lifter
ensures that the cables being lifted are not damaged by exceeding the
minimum bend radius.
Cable Block Lifter
Used in conjunction with a lay-up stick to place assorted cable blocks
mid-span.
Wire Raising Tool
Used in conjunction with a lay-up stick to lift cable blocks and strand.
Strand Brake
This device is selectively placed at pole hardware locations to prevent
dangerous strand sag while strand is being installed. The strand brake
allows the strand that is being pulled into place to move in only one direction,
which is the direction of the strand pull. Use of strand brakes in conjunction
with reel brakes effectively limits the amounts of strand sag between poles during strand installation.
14.9Appendix
Equipment/Cutting and Stripping
Equipment/Fiber Preparation and Splicing
Buffer Tube Cutter
These are used to score
drop, central tube and
stranded loose tube
buffers to facilitate
exposing the fibers.
Fiber Cleaver (Hand Held)
Fiber cleavers score and then trim the fiber. Price
and complexity of cleavers vary widely - generally,
the more you spend, the greater the consistency of
the cleave. The beaver tail cleaver shown
is a lower cost model.
Coating Stripper
This device mechanically strips fiber coating using precision blades and preset openings in much the same
way as a wire stripper takes insulation off
a copper wire. After the coating
has been stripped, the fiber
is cleaned with a solution
of 95% or higher isopropyl
alcohol.
Fiber
Cleaver
(Free
Standing)
This is a larger and more expensive
version of a cleaver. Its main
advantage is that it performs
accurate cleaves more
consistently than the
hand-held models.
Fusion Splicer
Most low-loss splices are made with fusion splicers, which use an electric arc to fuse together the cleaved ends of
fibers. Splicers vary widely in complexity, features and price. Some automate the entire splicing process. An applicable
splicer for CommScope fiber optic cables would have:
• a fusion heat source, usually an electric arc
• V-groove clamps for holding the fibers
• a way of positioning the fibers for optimum splicing
• a way of viewing the fibers (microscope, display screen) so they can
be accurately positioned
• LID (Local Injection and Detection) and/or PAS (Profile
Alignment System) to aid with fiber alignment
Appendix14.10
Back-Pull/Stationary Reel Set-Up
Installation - Back-Pull/Stationary Reel Set-Up
The back-pull/stationary reel method is the usual method of cable placement. The cable is run from the
reel up to the strand, pulled by a device that only travels forward and is held aloft by cable blocks. Excess (slack)
loops are formed during the pull. Lashing takes place after the cable is pulled.
Set-Up Roller-Block Placement
The set-up block should be positioned on the first pole of the cable route. Do not position set-up or take-down
blocks on the span. They should only be placed on a pole. Placement of the set-up block should keep the cable
from rubbing on the reel or pole. A 45° roller block should be used at the set-up pole.
Trailer Set-Up
The trailer should be positioned in-line with the strand and twice the distance of the set-up block to the ground from
the chute. This prevents the cable from rubbing on the pole (or reel) or binding on the block. If the trailer cannot be
positioned there, move the set-up block and cable trailer to an adjacent pole.
The cable should pay-off the top of the cable reel. The pay-off of the cable from the reel should cause a downward
force at the hitch of the trailer.
Chock the trailer wheels. Adjust the reel brakes as needed. Place protective barriers and cones as needed to
protect pedestrians.
Disclaimer
Legal Disclaimer
THIS MANUAL IS PROVIDED FOR GUIDANCE PURPOSES ONLY AND SHOULD NOT BE USED OR IN ANY WAY
RELIED UPON WITHOUT CONSULTATION WITH AND SUPERVISION OF EXPERIENCED CONSTRUCTION
PERSONNEL, ENGINEERS OR NETWORK DESIGN SPECIALISTS. COMMSCOPE MAKES NO REPRESENTATIONS
OR WARRANTIES OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING ANY REPRESENTATION OR WARRANTY
REGARDING THE QUALITY, CONTENT, COMPLETENESS, SUITABILITY, ADEQUACY OR ACCURACY OF THE DATA
CONTAINED HEREIN. COMMSCOPE IS UNDER NO OBLIGATION TO ISSUE ANY UPGRADES OR UPDATES OR
NOTIFY CUSTOMERS/USERS OF THIS MANUAL THAT CHANGES HAVE BEEN MADE TO THIS MANUAL. THE USER
OF THIS MANUAL ASSUMES ALL RISKS ASSOCIATED WITH SUCH USE, AND COMMSCOPE HEREBY DISCLAIMS
ANY AND ALL LIABILITY FOR DAMAGES OF ANY KIND RESULTING FROM SUCH USE.
www.commscope.com
Visit our website or contact your local CommScope representative for more information.
© 2014 CommScope, Inc. All rights reserved.
All trademarks identified by ® or ™ are registered trademarks or trademarks, respectively, of CommScope, Inc.
This document is for planning purposes only and is not intended to modify or supplement any specifications or warranties relating to CommScope products or services.
CO-107147.2-EN (11/15)
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