Patch Cord Installation Practices
This document has been produced by Brand-Rex to assist the installer with best practices
for Patch Cord installation. Information within has been sourced from the Brand-Rex
installation manual, many years experience in the industry and standards documents.
Together this information should assist the installer and answer many of the usual
questions surrounding patching installation.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 1 of 35
Revision Control
Issue
Date
1.0
01-04-12
BR_TSS_Patch_Cable_Installation_Pract
ices
Reason
Document Creation
April 2012
Updated by
T.Simmons
Page 2 of 35
Contents
Section 1 Copper Patch Cords
Content
Page
1 CABLE INSTALLATION PRACTICES
1.1
1.2
1.3
1.4
1.5
Bend Radii
Copper Pulling Forces and Twisting
Dressing of Cables
Cable Labelling
Cable Protection
6
7
8
8
8
2 ADDITTIONAL RULLES FR 10GPLUS PATCH CABLES
2.1
2.2
2.3
Alien Crosstalk
Mitigation Techniques
Patch Cord Management
9
9
10
3 PATCHING GUIDELINES
3.1
3.2
3.3
3.4
Patching Good Practices
Temporary Patches
A Tidy Frame
Routing Patch Cables
11
12
12
13
4 CABLE MANAGEMENT
4.1
4.2
4.3
4.4
Cable Management Bars
Blanking Panels
Angled V Panels
High Density Patching Frame
14
15
15
16
Section 2 Fibre Patch Cords
Content
Page
5 TIA/EIA 568C-3 Optical Patch Cords
5.1
5.2
5.3
5.4
General
Patch Cord Cable
Patch Cord Connectors
Termination Configuration
5.4.1
Duplex System
5.4.2
Simplex System
5.4.3
Array System
5.4.3.1
General
5.4.3.2
Optical Fibre Patch Cord
5.4.3.2.1
Type A Optical Fibre Patch Cord
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
18
18
18
18
18
18
19
19
19
Page 3 of 35
Section 2 Fibre Patch Cords (continued)
Content
Page
5.4.3.2.2
Type B Optical Fibre Patch Cord
5.4.3.2.3
Type C Optical Fibre Patch Cord
5.4.3.2.4
A to B Patch Cord (Standard)
5.4.3.2.5
A to A Patch Cord
5.4.3.3
Transition
6 FIBRE PATCH CORDS
6.1
6.2
6.3
6.4
6.5
6.6
6.7
6.8
6.9
Bend Radii
Optical Losses
6.2.1
Macro Bending
6.2.2
Micro Bending
Polished Ends
6.3.1
Polished Connector (PC)
6.3.2
Angled Polished Connector (APC)
Fibre Types
Connector Types
Patch Cord Types
6.6.1
Simplex
6.6.2
Duplex
Hybrid Patch Cords
Fibre Breakout Cables
Secure Fibre Patching
7 OPTICAL PATCH CORD MAINTENANCE
7.1
7.2
7.3
7.4
7.5
Lint Free Wipes
Individual Pre-Saturated IPA Wipes
Optical Fibre Cleaning Cassette & Tape
Swabs
Ferrule Cleaner
8 OPTICAL PATCH CORD TESTING
8.1
8.2
Optical Microscope
Types of Fibre Faults
8.2.1
Chip
8.2.2
Crack
8.2.3
Scratch
8.2.4
Broken Fibre
BR_TSS_Patch_Cable_Installation_Pract
ices
20
20
21
21
22
23
24
24
25
25
26
26
27
27
28
28
29
30
30
31
31
32
33
34
34
35
35
April 2012
Page 4 of 35
Section 1
Copper Patch Cords
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 5 of 35
CABLE & PATCH CORD INSTALLATION PRACTICES
1.1.
Bend Radii
The bending radius is defined as a multiplication factor of the outside cable
diameter. There are two relevant minimum bending radii: one for patch cord
installation and one for the patch cord once it is installed (without mechanical
load).
It is important to note that the minimum permissible bend radii of a cable is
greater during the installation / pulling in stage, when the cable is under
tension, than it is when the cable is placed in its final position and is free from
tension. This criteria is also applicable when installing/dressing patch cords.
Minimum bend radii must be observed throughout the whole cable route in
order to ensure that the design performance of the cable is not impaired.
XR
XR = min radius during installation
8 x sheath diameter
IR= min radius installed
4 x sheath diameter
IR
It is also important to consider bend radii when determining the size of
containment systems such as basket tray, conduit or trunking, as the system
may have adequate capacity for the straight runs but be too small at the turns
for the minimum bend radii to be observed. Tray work should have gussets
fitted to the inside edge of corners and conduit systems constructed to ensure
that minimum bend radius is not infringed.
The same applies to containment within cabinets, around frames and between
patch panels.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 6 of 35
1.2.
Pulling Forces and Twisting

Maximum pulling forces should not be infringed to ensure that the cable is not
damaged or its performance impaired during installation.

Ensure that adequate containment, patch management is available.

Minimise the twisting, pulling and bending of patch cords during installation..
The following installation parameters must be observed for four pair cables this
table should always be referenced for patch cord installation:Parameter
Units
4 pair U/UTP
Unit*
4 pair F/UTP
Unit *
4 pair S/FTP
Unit*
Temperature rating:
Installation
Operation
Storage
oC
oC
oC
0 to 50
-20 to 60
-40 to 60
0 to 50
-20 to 60
-40 to 60
0 to 50
-20 to 60
-40 to 60
Min. bending radius
During installation
Installed
mm
mm
40
20
Max. pulling load
N
85
GigaPlus
50
25
60
30
85
85
CAT6Plus
Min. bending radius
During installation
Installed
mm
mm
50
25
Max. pulling load
N
70
PIMF
70
35
95
10GPlus
Min. bending radius
During installation
Installed
mm
mm
Max. pulling load
N
Min. bending radius
During installation
Installed
mm
mm
Max Pulling Load
N
72
36
N/a
N/a
PIMF
65
32
98
N/a
10G Plus Zone Cable
U/FTP
N/a
45
N/a
22
N/a
N/a
N/a
N/a
98
95
During installation, cable management precautions that should be observed
include the elimination of cable stress caused by excessive tension, sharp bends
and tightly bunched cords.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 7 of 35
Temperature variations should not exceed those stated above, it should be
noted that attenuation increases with temperature, typically 0.4% per C for
Cat5e cables.
1.3.
Dressing of Cables
Dressed into neat groups and fix into place using the patch management
systems.
It is good practice to keep the groups as small as possible; this will aid cable
identification and future maintenance.
1.4.
Cord Labelling
ANSI/TIA/EIA 606A is the latest labelling standard that covers labelling
standards across your cabling infrastructure.
It does not mention that individual patch cords should be labelled but it can be
good practice to do so. If you do choose to label, 606A states that the use of
printed self-laminated wrap around labels is recommended.
There are many guides available on the web that covers the requirements of this
standard or a copy can be purchased at –
http://global.ihs.com/search_res.cfm?RID=TIA&INPUT_DOC_NUMBER=TIA-606
1.5.
Cord Protection
Take care to prevent damage to cords during and after installation.
Where possible all redundant cords should be removed.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 8 of 35
2. ADDITIONAL RULES FOR 10GPLUS CABLES
2.1.
Alien Crosstalk
Alien crosstalk (AXT) is electromagnetic noise that can occur in a cable that runs
alongside one or more other signal-carrying cables. The term "alien" arises from
the fact that this form of crosstalk occurs between different cables in a group or
bundle, rather than between individual wires or circuits within a single cable.
Alien crosstalk can be particularly troublesome because, unlike simple crosstalk
caused by a single interfering signal, it cannot be eliminated by the phase
cancellation techniques used in Digital Signal Processing. Alien crosstalk arises
from multiple signals, from multiple cables and includes mixing products in
which signals at innumerable frequencies blend with the originating signals.
The result is a mix of electromagnetic interference that is too complex to be
dealt with by Digital Signal Processing measures. Because it resembles noise
rather than signals, alien crosstalk degrades the performance of a
communications system by reducing the signal-to-noise ratio (SNR).
2.2.
Mitigation Techniques
Alien crosstalk can be minimized or eliminated by avoiding configurations in
which cables are bundled together or run parallel to one another in close
proximity.
In the first part of the link is imperative and non-more so than the patch lead,
not to run the cables or patch leads perfectly parallel to each other, or cable tie
them together or dress them in cramped cable management products. Avoid
cable management products that will compress or kink the cables and in the
case of cable ties ensure that they are not over tensioned. If a cable tie has been
over tightened then the balance of the cable will be affected. This will make this
area of the cable susceptible to noise.
Use patch panels that stagger the jacks or leave additional space between the
jacks. The additional spacing will dramatically reduce the effects of alien
crosstalk.
Shielded solutions may well be one very practical approach in reducing alien
crosstalk. The foil, and foil and braid types, will act as a screen to alien crosstalk.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 9 of 35
The use of shielded patch leads will dramatically reduce alien crosstalk and
Brand-Rex recommends their use on all 10G Plus installations.
As with any shielded system the earthing and bonding arrangements are
paramount to their success and any shielded system must be installed and
designed by trained and experienced installers of shielded systems.
2.3.
Patch cord management
When designing patch cord management systems it is important to understand
what the maximum capacities and performance is required.
Avoid running Copper and Fibre patch cords in the same management routes.
Important Note
Try not to mix cable types in the same paths as 10GPlus products. If you must
lay 10GPlus cables in the same paths as CAT5 or CAT 6 cables then leave at least
a 10mm space between them.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 10 of 35
3 Patching Guidelines
3.1
Patching Good Practice
Ports 1-12












Ports 1-12 patch to the left side of the cabinet
Ports 13-24 patch to the right side of the cabinet
1U Management Bar for every 2 panels of patching
Copper and Fibre patching to be separated as much as possible
Beware of servers on rails that need to move
Avoid obstructing removal switch blades and cooling fans
Use correct lengths to avoid bird’s nest
Make sure correct patching cabinets are used
Always remove redundant cords
Ensure no service exists before disconnecting or re-patching
Always use Brand-Rex patch cables on a Brand-Rex installation to keep the 25 Year
Warranty
Avoid “through Cabling” patching from one side of the frame to the other should be
avoided if possible. If unavoidable, make sure the cabinets are installed with
sufficient management bars to cope i.e. 2U top, middle and bottom.
BR_TSS_Patch_Cable_Installation_Pract
ices
Ports 13-24
April 2012
Page 11 of 35
3.2.
Temporary Patch Cables
If allowed, temporary patch cables can mount
up to look like this. One thing leads to
another and 6 months after a new installation
you’re faced with an unmanageable patching
frame and ££££’s of re-patching bills.
Time to fix faults and moves and changes can
take up to 10 times longer. After all “Time is
money”!!!
Cables protruding from the cab can also be a
Health & Safety issue as well as increase the
risk of accidental disconnection of circuits.
3.3.
A Tidy Frame
Keep your frame looking like this and your
patching can be achieved in a fraction of the
time.
Unique ID’s on patch cables and the use of a
patching database will help quickly identify
cables which will save time and money on
each patch change.
With a tidy frame, capacity can also easily be
monitored.






Label patch cables with a unique number to help identify leads.
Use the correct Category patch cords to match the installed system. The link will
only be as good as the slowest part of the network.
Avoid sharp bends in cables, this will increase attenuation.
Make sure cables are tidied inside cabs. Cables protruding can cause trip hazards
and may get trapped in floor tiles.
Use Brand-Rex Angled V panel to reduce number of bends in patch cords
Never install “Temporary” patches, they never get patched correctly and are usually
left on the frame.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 12 of 35
3.4.
Routing Cables
Follow the 10 Rule Guide to maintaining patching frames and you will help
keep your frame in a good condition.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 13 of 35
4 CABLE MANAGEMENT
4.1
Cable Management Bars
Ensure there are sufficient cable management bars installed in the cabinets.
Brand-Rex manufacture a range of panels as above. If using regular 24 port
copper patch panels it is recommended to install 1 x 1U Cable management bar
for every 2 patch panels.
If using the Brand-Rex angled V 24 port patch panels it is not necessary to use a
management bar, however a finger system should be installed vertically to take
the weight of the patch cables and keep them managed.
Most patching frames require inter-cab patching. Routing these longer patch
cables through the cabinet 1U management bars should be avoided. To enable
best practices a 2U management bar should be installed Top, Middle and Bottom
of the frame, this will avoid congestion for patch cables within the cabinet.
It should be noted that this is best practice and the use of 2U cable management
bars will greatly reduce the frames capacity. A well designed system should
avoid inter-cabinet patching with a single patch cord as much as possible, this
can be achieved by distributing the services regularly
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 14 of 35
4.2
Blanking Panels
Brand-Rex also manufactures a range of Blanking panels for cabinets. Primarily
these are designed to fill U space in cabinets to allow the correct circulation of
air and allow the air conditioning to operate efficiently.
Another good feature of the blanking panel is they prevent temporary patch
cables being installed from front to back, can help reserve U space for future
panels and keep the cabs/frames looking neat and tidy.
4.3
Brand-Rex Angled V Panels
Brand-Rex have designed an Angled V Panel to assist with the growing demands
within a patching cabinet. The panel allows more patch panels in each rack as
the modules are angled to the side so that patch cables naturally flow into the
management at the side (should be used with finger management). As the
modules are angled to the side the 90 degree bend that normally occurs with
patch cables is removed, when installing 10G systems every loss saving counts.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 15 of 35
4.4
Brand-Rex High Density Patching Frame
Vertical Finger Management
The Brand-Rex High density patching frame is designed to house a higher
number of patch panels than a regular patching rack. By using the Angled V
panel seen in section 4.3 along with the vertical finger management system
you no longer need the 1U cable management bars, this could save as much
as 8U per rack. If patching between different racks it is still recommended to
use a 2U management bar to allow for “through” patching.
The high Density patching Frame can be used for both Copper and Fibre
installations.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 16 of 35
Section 2
Fibre Patch Cords
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 17 of 35
5
TIA/EIA 568-C.3 Optical Patch Cords
Section 5 has been taken directly from the 568C-3 standard. Heading numbers are as they are found in
the standard document.
OPTICAL FIBER PATCH CORDS
5.1 General
This clause contains the performance specifications for optical fiber patch cords recognized in
premises cabling standards. These patch cords are used to connect optical fiber links at crossconnects, interconnects, and to connect telecommunications equipment.
NOTE - Requirements for application specific assemblies are outside the scope of this Standard.
5.2 Patch cord cable
The optical fiber patch cord shall contain the same number of fibers as the connector used (e.g.,
duplex connectors using duplex patch cord cable), be of the same fiber type as the optical fiber
cabling, of an indoor construction, and meet the requirements of subclauses 3.2 and 3.3.1.
5.3 Patch cord connectors
The patch cord connector shall meet the requirements of subclause 4.2.
5.4 Termination configuration
5.4.1 Duplex system
Duplex optical fiber patch cords shall be of an orientation such that Position A goes to Position B on one
fiber, and Position B goes to Position A on the other fiber of the fiber pair (figure 3). Each end of the optical
fiber patch cord shall be identified to indicate Position A and Position B if the connector can be separated
into its simplex components. For alternate connector designs utilizing latches, the latch defines the
positioning in the same manner as the keys.
Figure 3 - A-to-B duplex optical fiber patch cord
NOTE – SC connectors are shown, but this assembly may be built using any duplex
single-fiber connectors or connectors with two fixed fibers.
5.4.2 Simplex system
The connector that plugs into the receiver shall be considered Position A, and the connector that plugs
into the transmitter shall be considered Position B.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 18 of 35
5.4.3
Array system
5.4.3.1
General
Each of the three array system methods illustrated in ANSI/TIA-568-C.0, requires a specific combination
of components (array patch cables, transitions, duplex patch cords) to maintain polarity. Some of the
components are common to other connectivity methods such as duplex systems.
5.4.3.2
Optical fiber cable or patch cord
The cables or patch cords should be clearly identified.
NOTE - The patch cord shown is unpinned on both ends. In some instances, such as when
supporting parallel signals, it may be necessary to use a combination of unpinned and pinned
connectors on cables and patch cords. (Move in general of cables)
5.4.3.2.1
Type-A optical fiber cable or patch cord
As shown in figure 4, a Type-A connector patch cord has a sequential number assigned to each fiber as
follows:
a) On one end of the patch cord, the fibers are fixed within the array connector in consecutive
number (1,2,3,4…12) from left to right as viewed looking at the end-face of the connector with the
connector key up.
b)
On the other end of the patch cord, the fibers are fixed within the array connector also in
consecutive number (1,2,3,4…12) from left to right as viewed looking at the end-face of the
connector with the connector key up.
Figure 4 - Type-A optical fiber cable or patch cord (key-up to key-down)
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 19 of 35
5.4.3.2.2
Type-B optical fiber cable or patch cord
As shown in Figure 8, a Type-B array connector patch cord has a sequential number assigned to each
fiber as follows:
a) On one end of the cable, the fibers are fixed within the array connector in consecutive number
(1,2,3,4…12) from left to right as viewed looking at the end-face of the connector with the
connector key up.
b) On the other end of the cable, the fibers are fixed within the array connector in reverse
consecutive number (12,11,10,9…1) from left to right as viewed looking at the end-face of the
connector with the connector key up.
When MPO connectors are used in the construction of these cables they shall be flat polished
Figure 5 - Type-B optical fiber cables or patch cord (key-up to key-down)
5.4.3.2.3
Type-C optical fiber cable or patch cord
As shown in figure 9, Type-C patch cords have a sequential number assigned to each fiber as follows:
a) On one end of the cable, the fibers are fixed within the array connector in consecutive number
(1,2,3,4…12) from left to right as viewed looking at the end-face of the connector with the
connector key up.
b) On the other end of the cable, the fibers are pair-wise flipped within the array connector (2,1;
4,3; 6,5…12,11) from left to right as viewed looking at the end-face of the connector with the
connector key up.
Figure 6 - Type-C optical fiber cable or patch cord (pair-wise flipped, key-up to key-down)
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 20 of 35
5.4.3.2.4
A-to-B patch cord (standard duplex patch cord)
The A-to-B patch cords shall be built as specified in subclause 5.4.1.
5.4.3.2.5
A-to-A duplex patch cord
As shown in figure 7, A-to-A duplex patch cords shall be built as specified in subclause 5.4.1, except
Position A shall be routed to Position A and Position B routed to Position B.
A-to-A patch cords do not reverse the fiber positions. The A-to-A Duplex optical fiber patch cords shall be
of an orientation such that Position A goes to Position A on one fiber, and Position B goes to Position B
on the other fiber of the fiber pair (figure 3).The A-to-A duplex patch cords shall be clearly identified (by
color or prominent labeling) to distinguish them from A-to-B patch cords.
NOTE – SC connectors are shown, but this assembly may be built using any duplex single-fiber
connectors or connectors with two fixed fibers.
Figure 7 - A-to-A duplex optical fiber patch cord
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 21 of 35
5.4.3.3
Transition
As shown in figure 5, transitions have a sequential number assigned to each fiber as follows:
a) On one end of the transition the fibers are fixed within the array connector in consecutive number
(1,2,3,4…12) from left to right as viewed looking at the end-face of the connector with the
connector key up.
b)
On the other end of the transition the fibers are fixed within the connectors in consecutive
numbering (1,2; 3,4; 5,6…11,12) from left to right as viewed looking through the adapters with the
adapter key up.
Figure 8 - Array optical fiber transition
NOTES
1 – SC connectors are illustrated; however this assembly may use single-fiber connectors or connectors
with two fixed fibers.
2 – For ease of illustration, this transition is shown with duplex adapters, although they are not necessarily
part of the assembly
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 22 of 35
6
FIBRE PATCH CORDS
6.1 Bend Radii
Due to the sensitivity of most Fibre the bend radii is different to that of copper. The
bending radius is defined as a multiplication factor of the outside cable diameter.
There are two relevant minimum bending radii: one for patch cord installation and
one for the patch cord once it is installed (without mechanical load).
It is important to note that the minimum permissible bend radii of a cable is
greater during the installation / pulling in stage, when the cable is under
tension, than it is when the cable is placed in its final position and is free from
tension. This criteria is also applicable when installing/dressing patch cords.
Minimum bend radii must be observed throughout the whole cable route in
order to ensure that the design performance of the cable is not impaired.
XR = min radius during installation
15 x sheath diameter
XR
IR= min radius installed
10 x sheath diameter
IR
It is also important to consider bend radii when determining the size of containment
systems such as basket tray, conduit or trunking, as the system may have adequate
capacity for the straight runs but be too small at the turns for the minimum bend radii
to be observed. Tray work should have gussets fitted to the inside edge of corners and
conduit systems constructed to ensure that minimum bend radius is not infringed.
The same applies to containment within cabinets, around frames and between patch
panels.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 23 of 35
6.2.
Optical Losses
All optical fibres exhibit some loss or attenuation of the transmitted signal,
much of this loss is intrinsic, that is due to the glass itself. However other
conditions such as excessive bending connectors and splices also contribute to
the loss.
6.2.1.
Macro Bending
Macro bending loss shows up when fibre bend radius decreases, as
the bend gets tighter light rays within the fibre begin reflecting at
angles allowing them to pass through the cladding. The more the fibre
is bent the higher the attenuation.
6.2.2.
Micro Bending
Micro bending losses are caused by from stresses on the fibre such as
tight clamps and tie wraps pressing against the fibre. They can also be
caused by deviations in the core, measured from the axis of the fibre.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 24 of 35
6.3 Polished ends
There are 2 main typed of polished end for Fibre connectors, see below. The
Polished Connector (PC) is commonly used in Multimode cables and the Angled
Polished Connector (APC) is an option with the singlemode connectors.
6.3.1 Polished Connector (PC)
6.3.2 Angled Polished Connector
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 25 of 35
6.4
Fibre Types
Brand-Rex manufacture all types of Fibre Optic cable that may be required in
the DataCentre. Below is a table highlighting the types available. Fibre Patch
Cords are available in any fibre type.
OM1
62.5/125
OM2
50/125
OM3
50/125
OM4
50/125
OS1
8/25
OS2
8/125
62.5/125 was the industry standard 10 years ago however OM3 has now
become the customer choice as it more than meets the requirements of
todays network infrastructure.
As network demands are increasing the use of OM4 fibre is becoming more
popular.
NOTE: Make sure that the correct choice of cable is made when purchasing
new Fibre patch cords. If possible try to keep a standard across your site to
avoid future confusion.
6.5
Connector Types
Over the years there have been many different types of connector used to
terminate the fibre optic cable. Below is a list of some of the more popular.
Just as 62.5/125 multimode fibre was the most commonly installed cable, the
SC connector was the most popular.
The LC connector is now the preferred connector for all new installations.
However legacy cabling and equipment mean that you may need a cable to
convert from one type to another, see section 6.4 for the types available.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 26 of 35
6.6
Patch Cord Types
6.6.1 Simplex
Simplex is usually used to describe a single strand of Fiber Optic cable. This is
sometimes used when a signal only needs to go in one direction, like a simple
video feed from a security camera.
6.6.2 Duplex
Duplex (sometimes called "zipcord") is two strands of Fiber Optic cable
joined by a thin connection between the two jackets.
This is much more commonly used than simplex as with two fibers you can
get synchronous communication between devices. Duplex cables are often
labeled with A and B to determine which is the transmit and which is the
receive.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 27 of 35
6.7
Hybrid Patch Cords
As explained in section 6.3 is may be likely that you will need to convert from
one connector to another when patching a circuit. It may be because you
have an LC presentation for your cabling infrastructure and your equipment
only has SC or ST connectors. If the ports on your equipment are modular, it
may be best to upgrade to the LC module to try and keep the requirements
for patching infrastructure as simple/standard as possible.
Brand-Rex manufacture all cable varieties below and in a range of lengths.
1m, 2m, 3m and 5m are the standard lengths however different sizes can
easily be supplied.
Cable Varieties (Duplex)
LC-LC
LC-SC
LC-MTRJ
6.8
SC-ST
ST-MTRJ
MTRJ-MTRJ
ST-ST
MTRJ-SC
LC-ST
FC-FC
SC-SC
MTP-MTP
Fibre Breakout Cables
Although not really a patch cable, Fibre breakout cables are being use more
commonly in the data centres as part of the new MTP design. A 12 core
cable between point A and B can be installed and then a breakout assembly
connected via an MTP connector. Therefore a fibre core can easily be
patched to 6 LC duplex ports on a piece of equipment.
This is a simple way to install 12 cores using a plug and play design,
removing the need to field terminate or splice on site.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 28 of 35
6.9
Secure Fibre Patching
Secure Fibre patching is a new product from Brand-Rex which gives you the
opportunity to lock patch cords in place or block ports that you don’t want
used. This product has a high value in secure customer environments or for
important/critical circuits that should not be accidently disconnected.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 29 of 35
7 OPTICAL PATCH CORD MAINTENENCE
It is highly important to ensure you have a clean Fibre Optic infrastructure.
Cleaning new and existing patch cords before each insertion into a coupler is
critical. There are also methods of cleaning the fibre coupler to guarantee
you are maintaining your physical network in the best possible way.
Section 7 highlights some of the products that can be used to maintain your
fibre network.
7.1 Lint Free Wipes
Lint free wipes are one of the most basic methods of cleaning your fibres,
Lint free and non abrasive to ensure you are left with a clean fibre. To be
used with IPA solution.
7.2
Individual Pre-saturated IPA Wpies
IPA wipes provide the same solution as the Lint Free wipes above but are
supplied pre-saturated for convienience.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 30 of 35
7.3
Optical Fibre Cleaning Cassette and Tape
Great alternative to alcohol or other cleaning solutions.
Offers lint-free, clean room grade cleaning media which effectively removes dirt,
dust, oil, grease and debris from connector end faces.
Resilient rubber pad beneath the cleaning surface prevents scratching.
Sliding cover protects the cleaning media from contamination when not in use.
Reel refills available.





7.4
Swabs
Used for cleaning connector ferrule end faces, adaptors and difficult areas.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 31 of 35
7.5
Ferrule cleaner









BR_TSS_Patch_Cable_Installation_Pract
ices
Easy pushing motion engages connector and initiates cleaner.
Minimum of 800 cleans
Made from anti static resin
Cleaning micro fibers are densely stranded and debris free.
Extendable tip allows acces to hard to reach recessed connectors.
Cleaning system rotates 180 degrees for optimim cleaning.
Audible click to inform when engaged.
Compliant with EU/95/2002/EC Directive
(RoHS).
Effective with a variety of contaminants.
April 2012
Page 32 of 35
8 OPTICAL PATCH CORD TESTING
8.1
Optical Microscope
Optical microscopes come in a variety of shapes and sizes. Pictured above is
an example of 2 portable units. Each have connectors that can be easily
changed to suit the type of fibre connector being checked.
When looking through the microscope you should be looking for obvious
signs of dirt and contaminants. After the connector has been cleaned you
should see a perfect surface.
Section 8.2 indicates some of the more severe faults that can be found when
viewing the connectors.
Before Clean
After Clean
Without the use of a microscope it may be that by blowing on the connector
or rubbing it on your shirt may be good enough but such actions lead to the
image on the left. By using the microscope it’s clear to see the contaminants
on the surface. A clean or maybe a re-polish may be needed to bring this
connector up to spec.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 33 of 35
8.2
Types of Fibre Faults
8.2.1 Chip
These show up as dark areas off to one side of
the fibre. They are usually caused by poor
cleaving of the excess fibre, resulting in a crack
extending beneath the connector end face.
Because the ceramic is harder than the fibre, this
section of the fibre cannot be polished and so
remains dark.
Acceptance: Chips on the core or on the inner
cladding are unacceptable. Chips in the outer
cladding region extending more than 25% round
the circumference are also unacceptable.
8.2.2 Crack
Dark lines, often going straight through the
middle of the core, or looking like crazy paving
indicate cracks. These often show up more
clearly when the connector is back illuminated.
These cracks are caused by excessive heating or
uneven curing of the epoxy resin. They are rarely
seen when a properly temperature controlled
curing oven is used, but are much more common
if heat guns are used.
Acceptance: Cracks on the core or on the inner
cladding are unacceptable. Cracks in the outer
cladding region extending more than 25% round
the circumference are also unacceptable.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 34 of 35
8.2.3 Scratch
When multiple lines run parallel to each other
this usually indicates that the end face is
scratched. This may be due to dirt and dust
contaminating the polishing paper, or by
neglecting to clean the polishing puck and
connector face when moving from a coarse grade
of lapping film to a finer one.
Acceptance: The core should be free from
scratch defects.
8.2.4 Broken Fibre
If the fibre is broken, no light will get through.
This will result in a dark ring from the cladding
to the core of the fibre.
Acceptance: Broken fibres are unacceptable.
If further assistance/guidance is required then please contact our Technical support team on techsupport@brand-rex.com
and your enquiry will be dealt with promptly with a relevant engineer assigned. More information on everything from
Datasheets and White Papers to our latest training videos can also be found on the Brand-Rex website www.brand-rex.com.
BR_TSS_Patch_Cable_Installation_Pract
ices
April 2012
Page 35 of 35