Designing NEXUS - Getty Associates

Wherever you are, you can depend on Nexus
to get the job done!
What is NEXUS ? :
For Thomas & Betts, NEXUS is a real-time network management system for
emergency lighting and exit signs. It enables the user to manage the entire
installation – installing and removing components, testing and monitoring the
system and managing maintenance activities thus saving time and money on
maintenance.
MAKING YOUR LIFE EASIER AND YOUR BUILDING SAFER
Design & Installation Guide
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© 2006. Thomas & Betts Limited. All rights reserved. Printed in Canada 06/06/150 Order no. NEXUSDESIGN&INSTALL.GUIDE-E
Leading the Way!!
Design & Installation Guide
Nexus System Solutions
Table of Contents
Introduction to NEXUS
1
Features
1
Introduction to emergency lighting
2
Nexus Design Section
6
Designing NEXUS
7
Before You Begin
7
18 Steps to a Successful NEXUS Design
7
Step 1:
Step 2:
Step 3:
Step 4:
Step 5:
Step 6:
Step 7:
Step 8:
Step 9:
Step 10:
What You Will Need
Prepare Yourself
Plan the SPU Locations
Number the SPU’s
Select the Most Suitable Cable
Plan the Channel Routes
Plan the Router Locations
Plan the Repeater Locations
Plan the Terminator Locations
Mark the Channels, Routers, Repeaters, Terminators on the Plans
7
7
8
9
9
10
10
11
11
11
Check your Work
13
Step 11:
Step 12:
Step 13:
Step 14:
Step 15:
Step 16:
Step 17:
Step 18:
13
13
14
15
16
17
17
18
Plan the NEXUS Server Location
Mark the NEXUS Server Location on the Plans
Plan the Trunk Route
Mark the Trunk Route on the Plans
Number the Channels
Create the Materials List
Create the Project Specifications
Contractor (Installer) Requirements
Sample Consultant Specification
Emergency Lighting Fixtures
Computer Hardware
Computer Software
Communications
System Programming/Commissioning
19
19
19
19
19
20
Sample Typical High-rise Layout
21
Sample Typical Shopping Centre Layout
22
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Nexus System Solutions
Table of Contents
Nexus Installation Section
24
Communications and Emergency Lighting
25
NEXUS Topology
25
Before you Begin
27
What You Will Need
27
The NEXUS System
28
NEXUS System Specification
Emergency Lighting Fixture
Computer Hardware
Computer Software
Communication
System Programming/Commissioning
NEXUS System Components
Single point unit (SPUs)
Channel
Channels sequence numbers
Trunk
Routers
Repeaters
28
28
28
28
29
29
30
30
30
31
31
31
31
Channel Terminators
32
NEXUS server (Personal Computer)
32
Data Cable Types
33
Unshielded cable
33
Shielded cable
33
Select the Cable Size and Brand
33
Sample Diagrams
34
Sample Typical High-rise Layout
35
Sample Typical Shopping Centre Layout
36
Before you Install
Check the Plans and Specs
Installing the Cabling
37
37
38
Terminating Data Cable
39
Grounding Shielded Cables
40
Data Cabling Rules
40
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Nexus System Solutions
Table of Contents
Installing Routers (or Repeaters)
41
NEXUS Router
42
Example Router Connections:
Terminators
Repeaters
43
43
44
Example Router/Repeater Configuration 1 (Trunk):
44
Example Router/Repeater Configuration 2 (Trunk):
44
Example Router/Repeater Configuration 3 (Trunk):
44
Example Router/Repeater Configuration 4 (Trunk):
45
Example Router/Repeater Configuration 5 (Channel Branch):
45
Power Connection
45
Connecting Emergency Lighting Fixtures to the Network
46
Initial Testing of Emergency Lighting Fixtures
46
Preparation for Commissioning
46
Data Cable Connection
47
NEXUS Support
47
APPENDIX I: Glossary of Terms
48
APPENDIX II: Project Grid
51
APPENDIX III: SPU LED Colour Meanings
52
LED Colour Status Table
52
NEXUS Guide Feedback Sheet
53
NEXUS Support
54
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Nexus System Solutions
Introduction to NEXUS
This section presents an overview of the T&B NEXUS network. NEXUS is a computerised network
communications system primarily designed to monitor, remotely activate and report on the status of
NEXUS type single point emergency evacuation light SPUs in buildings .
Features
1. NEXUS is a labour-saving device that allows
the testing of a building emergency lighting system
from only one location.
Previously, the testing of a building required many
hours of labour for qualified staff to manually inspect
and test every emergency SPUs and record it in a
log book. Now, you can let the T&B NEXUS System
do it for you.
2. NEXUS can test and report on the status
of the entire emergency lighting in an installation
individually, in groups or all together. NEXUS
operates in real-time, indicating any change
of status of network components by changing
their icon colour in the NEXUS window.
3. The labour saving is achieved by using a
T&B NEXUS System to communicate between
the lights and the monitoring NEXUS Server.
Custom designed NEXUS software allows
the user to remotely activate the NEXUS SPUs
and retrieve status information from them.
Thus, maintenance personnel need only attend
to the SPUs that need repairing/attention.
4. NEXUS is self-monitoring and, in the event
of cable damage, can indicate the location
of the fault down to the particular CHANNEL,
which could save hours of manual fault finding.
5. The operation of the emergency lighting function
is neither impeded by nor dependent upon NEXUS.
NEXUS is simply used to monitor and remotely
activate the SPUs without the need to actually
sight each one for testing. Of course, any physical
maintenance such as cleaning and re-lamping
must still be done manually.
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6. A NEXUS SPU can be removed or added anywhere
on the NEXUS Network, without interruption to the
operation of the remainder of the system.
7. Other forms of network topology are prone
to interruption. Looped serial cables have the
disadvantages of propagation delay factors
that increase with the length of the loop and slow
the communications. A break anywhere in the loop
ceases communications within the loop.
Star connections that require separate input and
output cables are no more than a loop wired
in a star pattern. Proper Star topology networks
require sophisticated hub switching devices at the
centre hub of every star. T&B chose to use the bus
topology of a main line (backbone or TRUNK) with
multiple side lines (ribs or branches) connected
in an unpolarized daisy chain. The conductors are
not polarized (+ & -), thereby making connecting very
easy, requiring no metering polarity test equipment.
8. T&B also chose to use a single twisted pair cable as
the network medium because extensive study
showed that this was the most economical, reliable
and easy to install. Other media considered were
power-line, infrared, radio-frequency, fibre-optic and
coaxial cable, however they have shown to
be either uneconomical, unreliable, hard to install
or a combination of all three.
9. A NEXUS-equipped building should never be at risk
of inadequate emergency lighting. The completed
NEXUS installation can be divided into Groups for
testing purposes. By selectively alternating the
grouping of the emergency light SPUs, the
installation can be tested in stages so that not all
of the emergency lighting of the building is
in ‘recovery mode’ after a discharge test.
Nexus System Solutions
Introduction to Emergency Lighting
This section presents an overview of emergency lighting systems. It describes the function of emergency
evacuation lighting, the different types of emergency lighting fixtures and their uses, the different types
of emergency lighting systems, with their overall advantages and disadvantages.
Throughout this guide, the term emergency lighting is used generically and refers to both Exit and non-Exit
type emergency lighting fixtures. Those that do have an Exit sign attached are commonly referred to
as Exit lights, whereas those that have no Exit sign attached are commonly referred to as emergency
lighting fixtures.
NOTE: Emergency evacuation lighting is designed to automatically provide adequate lighting levels
and signage for the safe evacuation of humans from buildings in the event of electricity supply
failure to the normal lighting of the building.
Emergency Lighting Fixture Single Point Unit (SPU) Types
No matter which type of SPU you use, they are all connected to an unswitched permanent connected
120V or 347V AC power supply.
AC Supply Connections and Emergency Lighting
Unswitched
NOTE: All emergency lighting fixtures must be connected to an Unswitched supply.
The unswitched supply is used to charge the battery and is monitored to determine the supply status.
It therefore, must be present at all times to ensure reliable operation of the emergency function when
required.
Switched
Some emergency lighting fixtures have two input connections, switched and unswitched.
The non-emergency part of those fixtures can be turned ON and OFF in the same manner as conventional
light fixtures. Switching off the supply to the emergency part of the light fixture is not permitted.
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Nexus System Solutions
Emergency Lighting System Types
There are two main types of emergency lighting systems that are described by the location of their
emergency batteries:
• Central Systems, and
• Single Point Systems.
Central Systems
Description
Large, weighty banks of vented rechargeable batteries are wired together to create backup supplies for
emergencies. These are often located in one room along with their charging equipment and hard-wired
directly to all of the emergency lighting in the building. They generally operate at DC voltages of either 24,
50, 60, 110 or 120V. Central Systems are the older of the two system types. They were the only suitable
batteries available until the manufacture of small NiCad and lead-acid sealed batteries (that are used in
Single Point Systems) became economical and readily available in the 1970s.
Method of Operation
Their control is usually through hard-wired relays or contactors located within the system cabinet or the
lighting distribution switchboards of the installation. When the power to the local lighting circuit fails the
relay or contactor drops out and this in turn connects the low voltage emergency battery supply to the
emergency lights, via the normally open contacts. Hence, when the normal lighting fails, the emergency
lighting comes on.
Advantages
The advantages of a Central System are one location for the servicing of the equipment and maintenance
of the system batteries. Typical central system batteries, if maintained regularly can perform adequately
and last for a quarter of a century or more.
Disadvantages
The many disadvantages of a Central System are: its large initial cost involving the purchase of the battery
bank; the large charger equipment; the flame/flash proof room space and ventilation equipment necessary,
the batteries and charger location; the cost of installing the expensive large gauge distribution cabling
and control equipment for the DC circuits; the inherent dangers of Direct Current shock; and the large
ongoing maintenance costs.
Any changes to the layout of the floor plan that affects the location of the egress route in the event of
an emergency, requires the rewiring and relocation of the emergency lighting fixtures and the expensive
DC supply cabling. Any alteration to any part of the system requires the shutdown of all of that section
of the system during the change.
The maintenance of the batteries themselves can be a hazardous job involving the risks of explosions,
poisonous gases, acid burns and DC electric shock.
Central Systems cannot presently be connected to a computerized monitoring system and so require
a manual test and visual inspection of every emergency light every month to comply with The National
Fire Code of Canada (NFC 2005).
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Nexus System Solutions
Single Point Systems
Description
Single Point Systems contain small sealed rechargeable batteries and charging equipment located within
the light fixtures. Each fixture operates as a single stand-alone point known as a Single Point Unit (SPU) and
therefore does not require the operation of external or centralized control equipment to function in an
emergency.
Method of Operation
The batteries are charged by the normal electricity supply connected to the fixture.When the power to the
local lighting circuit fails, the internal circuitry of the emergency lighting fixture connects the low voltage
emergency battery supply to the emergency lamps. Hence, when the normal lighting fails, the emergency
lighting comes on to illuminate the area.
Advantages
The advantages of Single Point Systems over Central Systems are that they are less expensive to
purchase, to install and to maintain. They are more flexible in design in that any part of the installation
can be removed or added to without affecting the remainder of the system. Because the fixtures are
self-contained and can stand alone, there is no need for fireproofing the supply cabling to them.
None of the potentially hazardous Central System battery maintenance risks occur in Single Point Systems.
A more recent advantage is that Single Point Systems can now be centrally controlled via dedicated
communications networks and monitored by a PC program to aid in the maintenance of the system. The
computerized systems do not require manual inspection of the light fixtures every month as the computer
can tell the service personnel exactly which fixtures require attention and where they are located. The
computer can also contain and manage the logbook required under National Building Code of Canada.
Disadvantages
The disadvantage of Single Point Systems is that the smaller sealed cell rechargeable batteries have
a shorter Service Life than Central System batteries and so require replacement more often.
Communications and Emergency Lighting
Computerized emergency lighting systems are a combination of a communication network system and
emergency lighting distributed throughout a building. The network is used to communicate between the
emergency lighting fixtures and a centrally located controller, usually a computer. The network can pass
messages both to and from the emergency fixtures to either instruct the fixtures to do something (such
as turn on or off their emergency lamps) or to report back to the controller giving their status (such as
whether their lamps are working).
These computerized emergency lighting systems can and do use a variety of means to communicate.
The most common, inexpensive and reliable method uses a dedicated communications cable wired between
every emergency lighting fixtures and the controller. The method of communication within the
network, called the protocol, determines the way the communication cabling must be installed, connected
and used. Different brand emergency lighting systems, using different protocols, cannot be combined.
To have trouble-free operation of the communications system, the cable most suited to the type of
installation must be used, and the recommended design and installation procedures must be followed
in detail. It is not difficult, but does require attention to detail. The importance of correct cable selection
and installation can not be understated.
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Nexus System Solutions
Is this the right guide for you?
This guide is part of a series of user-friendly guides to help you design, install, commission, maintain and operate
the T&B NEXUS System.
Choose the correct guide to suit your needs.
If you don’t have the guide you need, ask for it from your T&B Representative.
Design & Installation Guide
NEXUS Design Section
NEXUS Installation Section
The NEXUS Design Guide is for the person
responsible for the design of the T&B NEXUS
System in buildings, and includes:
•
Technical information on NEXUS.
•
NEXUS design requirements and specifications.
•
A guide to selecting the correct communications cable.
•
Step-by-step NEXUS design procedure.
•
Sample consultant specifications.
•
Sample ‘typical’ NEXUS designs.
The NEXUS Installation Guide is for the person
responsible for the installation of the T&B NEXUS
System in buildings, and includes:
•
NEXUS terminology.
•
Pre-installation checklist and reminders.
•
NEXUS equipment installation requirements
and procedures.
Communications cable selection and connection details.
•
•
ROUTER/REPEATER installation procedure.
•
Using the Channel Tester to test communications.
•
Preparation for System Commissioning.
NEXUS Commissioning & End User Guide
This section is for the person responsible for testing and commissioning the installation and responsible for the operation
and use of the T&B Nexus System, and includes:
•
•
•
•
•
•
•
•
An introduction to the T&B NEXUS System.
NEXUS software installation requirements and procedures.
Commissioning the NEXUS Server, ROUTERS, REPEATERS, and SPUs.
Testing NEXUS SPUs and communication.
Report printing instructions.
Fault finding and problem resolution.
Service instruction generation and guidelines.
Upkeep of system records.
NOTICE
These guides were prepared to assist the people responsible for a NEXUS system.
• All information and recommendations are to the best of our knowledge, accurate at the time of writing.
• All specifications and tradenames registered or not, are the property of their respective owners.
• All specifications are subject to change without notice.
• Errors and omissions excepted.
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NEXUS
DESIGN SECTION
Everything you need to know
to fully plan and design a
T&B NEXUS
Network Control System for buildings
• Technical information on NEXUS.
• NEXUS design requirements and specifications.
• A guide to selecting the correct communications cable.
• Step-by-step NEXUS design procedure.
• Sample consultant specifications.
• Sample “typical” NEXUS design.
Nexus System Solutions
Designing NEXUS
Before You Begin
This guide will take you through the steps of designing a complete T&B NEXUS System. If you are experienced
in this, then simply use this guide as a reminder. If however, you are not experienced in the proper methods
of NEXUS design, T&B suggests that you read this complete guide through before you commence your design.
18 Steps to a Successful NEXUS Design
STEP
1
What You Will Need
This Design Guide:
Contains all of the design information, except that of National Building Code of
Canada 2005.
Electrical knowledge:
You should know about electrical installations according to the N.B.C.
Drafting experience:
You should be experienced in creating, reading and interpreting plan drawings.
Floor plans:
Plans of the proposed installation for marking up.
Drawing equipment:
Facilities to mark up the plans either by hand or by computer.
Consultant’s reference:
The owner’s fit-out guide and consultant’s specifications (if available and relevant).
STEP
2
Prepare Yourself
Collect all of the items listed in Step 1. Read the National Building Code of Canada and, using that
information, determine exactly where in your project building you should locate the emergency light fixtures.
NOTE: This NEXUS Design Guide does not attempt to tell you where you should locate the emergency
lights and exit signs. You must refer to the recommendation of your T&B technical representative.
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STEP Plan the SPU Locations
3
Locate the SPUs in a position that allows them to do their job, but also allows them to be easily installed and
maintained. Any location that would require an extension ladder, scaffolding or a crane
to gain access to the fixture is an unwise location for an emergency light. High-bay ceilings or directly
over the steps of a stairway or over a well or opening are all locations that should not be chosen.
Usually, there are walls, pillars or landings that will provide a far more accessible position for access
to the emergency lighting.
If the light fitting is too high, it will probably not provide enough light to comply with the N.B.C.
Cost of installation will be less if the installing electrician can reach the lights easily. In addition, on-going
maintenance costs will be minimized if the servicing electrician can reach the light (to change lamps, etc.).
UP
2-4
Offices
F/Str1
DN
2-3
2-5
2-2
Store
2-6
2-7
Electrical
Riser
Air Con
Duct
Key
2-1
2-8
SPU
Elevators
Mark up the plans to indicate the exact location of every SPU. Cable routes are added at a later stage.
NOTE: In the following examples, we have not differentiated between lighting fixtures and directional exits.
Some designers use the letters EX and arrows in a box
to symbolise a directional EXIT type fitting.
T1
T4
R4
Second
floor
T4
Branch line channel 4
4-1
4-2
4-4
4-3
4-5
4-6
4-7
4-8 etc...(up to 4-50)
T3
R3
First
floor
T3
Branch line channel 3
3-1
3-2
3-4
3-3
3-5
3-6
3-7
3-8 etc...(up to 3-50)
T2
R2
T2
Branch line channel 2
2-1
2-2
2-4
2-3
2-5
2-6
Key
2-7
2-8 etc...(up to 2-50)
SPU
Data Cable
Nexus server
R# Router
T# Terminator
T1
ADMINISTRATION BUILDING
Ground Trunk line
floor
channel 1
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STEP Number the SPUs
4
During the Commissioning Stage of the project, NEXUS issues each SPU with a unique Channel Sequence
Number from the database in the order they are wired/data cabled.
The Channel Sequence Number identifies each fitting as a function of its CHANNEL and its place on that
CHANNEL. For example, the first fitting on CHANNEL 2 will have a Channel Sequence Number of 2-1.
Channel Sequence Numbers can be skipped and reserved for later use. Additional SPUs can be added
to the system at any time. Any additional SPUs will be given the next available number from either the
sequential order, or one from the reserved list.
During the design stage of the project, you should mark a unique Channel Sequence Number on the plan
adjacent to the symbol for each SPU. T&B suggests that you number in sequence along the CHANNEL
routes. Start with 1 and keep going until every SPU is numbered. If you know where extra SPUs will be
added later, make allowance for them by reserving their sequential number positions now. Ensure that
each Channel Sequence Number is unique, as NEXUS will not duplicate numbers.
STEP
5
Select the Most Suitable Cable
Select the Cable Type
DATA CABLES
Must be treated as communications cables
and be physically protected from damage.
Communications cables
Must never be connected to AC supply.
Different DATA CABLE types have different characteristics which are better suited to carrying different
frequencies.
The DATA CABLE types that are rated Universal Laboratories (UL) Level 4 (or better) have been designed,
tested, proven and recommended for operating over the frequency range that NEXUS uses.
There are two main types of DATA CABLES that can be used for the NEXUS System: either Shielded
or Unshielded. Both are Twisted Pair, UL rated Level 4 (or better) Communication.
Use only the same cable type within a CHANNEL.
Use only the DATA CABLE types that are listed here. Other DATA CABLE types will not work properly in this
type of communications network and T&B (or their agents) will not commission improperly cabled projects.
The gauge of the wire directly affects the permissible maximum length of the CHANNEL. The sheathing of
the cable directly affects where it can be run. Choose the appropriate cable for the situation in which it is to
be used.
If multicore cables are used, the unused conductors must be individually connected and insulated
continuously throughout the length of the CHANNEL. They are to be grounded at one point only at the
ROUTER of that CHANNEL to prevent ground loops and possible communications interference. Only
the conductors of the same pair must be used. Separate pairs must never be connected in parallel
for any reason.
Unshielded cable
Unshielded cables are prone to picking up any extraneous electrical EMF-induced voltages and signals
(noise) which may interfere with the proper data communications and therefore should only be installed
where there is a low risk of noise interference.
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Shielded cable
Shielded cables are less prone to picking up noise when installed and terminated properly.
Shielded cables must be run for the whole length of a CHANNEL if:
• Any part of that CHANNEL could potentially pick up any noise.
• The DATA CABLE is run parallel with AC supply cables.
• The DATA CABLE passes through or near a magnetic field such as an electric motor or a radio room.
Select the Cable Size and Brand
If the DATA CABLE is to be run in the same enclosure or conduit as AC supply cables, then the DATA
CABLE insulation must be suitably rated, and the cable must be shielded.
Recommended DATA CABLE
STEP
6
DATA CABLE TYPE
UL/CSA
RATING (type)
Shielded Twisted Pair
CMG
FLAME RESISTANT
CSA
Plenum
BRAND
(reference only)
MAX CHANNEL
LENGTH
FT4
CMP FT6
CERCO AT-HOM29
1,000 (3250ft)
Plan the Channel Routes
You can connect up to a maximum of 140 CHANNELS on a NEXUS system. T&B recommends that there be
no more than 50 SPUs per Channel. Depending upon the physical layout of your particular project, arrange
the SPUs in such a way that up to 50 are linked together to form a CHANNEL.
The maximum length of any CHANNEL is up to 300, 600 or 1000 metres, depending upon the type of data
cable that you choose. See the previous section on cable selection for more details. In special situations
where you cannot arrange less than 50 SPUs together, or the planned CHANNEL cable length will exceed
the recommended maximum, you must add a REPEATER in the CHANNEL to boost the signals. This will
allow you to lengthen the CHANNEL wiring to have up to 100 SPUs on that CHANNEL (see Step 8: Plan the
Repeater Locations).
All wiring within fire stairwells must be fire-rated, so the less that is actually within the stairwell, the better.
If you specify the mounting of the SPU on a wall in a fire stairwell where the other side of the wall is
accessible, then non fire-rated wiring can be run through the wall directly into the back of the SPU.
Using this method, no fire-rated wiring needs to be run within the stairwell at all. The most expensive
alternative would be to specify that the wiring should run right up inside the length of the stairwell.
That must be fire-rated and/or physically protected with steel conduit.
NOTE: If you have not sequentially reference numbered the SPUs yet, do it as soon as you know
the layout of the CHANNELS.
STEP
7
Plan the Router Locations
Consider each CHANNEL connection to the TRUNK. Somewhere along the route of every CHANNEL,
there must be a ROUTER connection to the TRUNK (to allow data flow to and from the TRUNK and thus the
NEXUS Server). Consider the location of the ROUTER and remember that it must also be in a position that
can be readily accessed for installation, commissioning and maintenance purposes.
Each ROUTER requires a 120VAC receptacle so ensure that you specify that it has a power point within
reach (usually connected onto the same circuit that is servicing the SPUs in that area). T&B suggests that
you locate ROUTERS in Electrical, Data or riser cabinets, at eye level, to allow for ready access.
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STEP Plan the Repeater Locations
8
In some circumstances, it may be necessary to double the length of a CHANNEL by adding a REPEATER to
it. A REPEATER is just like a ROUTER, except that it does not connect to the TRUNK; rather it connects to
the end of a CHANNEL to extend the length of that CHANNEL only. The extended segment takes on the
identification of the CHANNEL it connects to so that both segments are regarded by NEXUS as having the
same CHANNEL number. The REPEATER simply transfers all communication traffic from one segment
of the CHANNEL to the other, effectively boosting and repeating the information for the benefit of the
extended segment.
Each REPEATER requires its own 120VAC receptacle just like a ROUTER and should be located
in a readily accessible and serviceable position as with a ROUTER.
The REPEATER is used to boost the data signal strength within the CHANNEL. It would be used in
situations where you require between 50 and 100 SPUs on the same CHANNEL and there is no TRUNK
cable within 100m (325ft) or so of this extended segment of the CHANNEL. A REPEATER could also be
used in situations where the route length of the CHANNEL will exceed the recommended maximum length
of the DATA CABLE type being used.
It may be more appropriate to select a different gauge wire cable type than to install a REPEATER that
requires service access and its own power point. It also may be more appropriate to run a separate
CHANNEL for the extended segment rather than using a REPEATER.
STEP Plan the Terminator Locations
9
Remember that both ends of every CHANNEL must also have a CHANNEL TERMINATOR connected
to them and that you must specify the location of both ends of every CHANNEL. Do not confuse an
electronic CHANNEL TERMINATOR with the usual electrical connecting terminator or connector. They
are not the same and cannot be interchanged. CHANNEL TERMINATORS are passive electronic devices
that do not require a power source and do not usually require servicing. However, the location of every
TERMINATOR should be specified and recorded so that it can be accessed in the future if need be,
such as to extend the CHANNEL.
You should specify the exact location of each TERMINATOR keeping in mind the practicalities of access
as discussed before. Often the CHANNEL will commence at the ROUTER location and a TERMINATOR
will have to be located there. TERMINATORS are small enough to fit within the housing of a ROUTER
or an SPU.
STEP Mark the Channels, Routers, Repeaters, Terminators on the Plans
10
Once you have planned the CHANNEL routes, ROUTER, REPEATER and CHANNEL TERMINATOR
locations, mark them up on the plans in the following manner.
Channel Data Cable Routes
The CHANNEL DATA CABLE route is represented on the plans as a line running from SPU to SPU
within the CHANNEL. Each CHANNEL will require a separate line to represent it. The line should be easily
distinguishable from any other lines on the drawing and no two CHANNEL lines should cross over each
other.
You have the choice at this stage of either detailing the exact route of the cable, (you may have cable
tray schematics), or you can specify an approximate route and leave the exact detail up to the installer.
The exact cable route will need to be defined by the installer as part of "As installed drawings".
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An easy-to-see method is used to chart the approximate cable route. This method is represented as curved
lines on the drawings and can be made quite easily identifiable (see below).
UP
2-4
Offices
F/Str1
DN
2-3
2-5
2-2
Store
2-6
2-7
Electrical
Riser
Air Con
Duct
Key
SPU
2-1
2-8
Data Cable
Elevators
Whichever method you choose, make it obvious and make it clear.
Routers
Where a CHANNEL meets the TRUNK, it must be connected through a ROUTER. Represent a ROUTER
by drawing a box with a capital R on it in the drawing. Leave space after the letter for the inclusion of a
CHANNEL identification number, to be added later when you number the CHANNELS. If you have the
facilities, make the ROUTER symbol a different colour or add a label so that there is no confusion regarding
its identity or location.
It should look something like this:
R#
and will eventually be numbered like this:
R2 .
NOTE: There is no R1 on the TRUNK. Its function is performed by the NEXUS Server. Your ROUTER
numbering should start at 2 and will match the numbering of the CHANNELS, i.e. R2 is connected to
and serves CHANNEL 2, and so on.
Repeaters
There may be circumstances where there is no alternative, so you must specify a REPEATER. Represent a
REPEATER by drawing a box with Rpt on it in the drawing.
It should look something like this:
Rpt
.
Channel Terminators
Both ends of every CHANNEL must be connected to CHANNEL TERMINATORS. Represent a
TERMINATOR by drawing a box with a capital T on it in the drawing. Leave space after the letter for
the inclusion of a CHANNEL identification number, to be added later when you number the CHANNELS.
If you have the facilities, make the TERMINATOR symbol a different colour ou add a label so that there is
no confusion regarding its identity or location.
It should look something like this:
T#
and will eventually be numbered like this:
T2
.
There will be two TERMINATORS with the same number on every CHANNEL, one at each end.
Just like the numbering of the ROUTERS, you number the TERMINATORS to match the numbering
of the CHANNEL they are connected to, i.e. T2 is connected to CHANNEL 2, and so on. The TRUNK
is CHANNEL 1 so it uses the T1s.
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Check your Work
By this stage, your drawing should be similar to the one shown below, showing:
•
•
•
•
•
Up to 50 SPU symbols per CHANNEL,
Sequential Channel Sequence Numbers,
CHANNEL DATA CABLE routes,
2 TERMINATORS per CHANNEL, and
1 ROUTER per CHANNEL.
NOTE: Check your drawings to make sure you haven’t missed any of these items.
UP
2-4
Offices
F/Str1
DN
2-3
2-5
2-2
Store
Electrical
Riser
Air Con
R2
Duct
Elevators
2-6
2-7
Key
SPU
Data Cable
2-1
T2
R# Router
2-8
T# Terminator
T2
NOTE: The TERMINATOR symbols are too large to fit in the cabinet next to the ROUTER or in the
SPU symbol, so we have drawn them in the passage way next to their CHANNEL ends. In this case,
you would add a note to the drawing to specify that the TERMINATORS are to be located within the piece
of equipment that is closest to the respective ends of the CHANNEL, i.e. within the ROUTER and Channel
Sequence Number 2-8.
It is good practice to make these items very visible on the drawings so that they are not forgotten by
the installer.
You should also have an installation list with at least the first four columns filled in and a row for every SPU.
Remember that this list works in conjunction with your plan drawings to form part of the project
specifications, and will eventually be the start of the installation database.
The Channel Sequence Numbering should make this crosschecking procedure relatively simple.
STEP
11
STEP
12
13
Plan the NEXUS Server Location
The NEXUS Server (PC) should be conveniently located for the NEXUS end user, usually in the Building
Manager’s or Maintenance Manager’s office. Do not specify the location of the NEXUS Server in an area
that is hostile to electronic equipment (such as in dusty, dirty, oily or humid areas, workshops, machine
shops, switch rooms, furnace, plant rooms, or near high traffic areas such as passageways and corridors).
The NEXUS Server will require two twin 120V receptacles, a desk with enough space for the one dedicated
phone line, computer and monitor, the printer and paper feeder and to spread out copies of the plans.
Mark the NEXUS Server Location on the Plans
Mark the position of the NEXUS Server on the plans
using a picture representation of a computer:
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STEP Plan the Trunk Route
13
Channel 1 is the TRUNK that makes the communications connection between the NEXUS Server
and every other CHANNEL of the installation. All data that flows within the network passes through the
TRUNK and the design of its route is most important for the efficient operation of the network. As stated,
the NEXUS uses the multidrop or tree topology consisting of a TRUNK and branches as shown below.
Trunk line
T1
R2
T1
R4
R3
Nexus server
T2
Key
SPU
Data cable
R# Router
T3
T2
T# Terminator
T3
T4
T4
Branch line
Branch line
Branch line
channel # 2
channel # 3
channel # 4
This can resemble a tree, if you can imagine it on its side with hanging branches on both sides of the
TRUNK as shown on page 14. Because the TRUNK is the most used section of data cable in the network,
and because it links all the CHANNELS to the monitoring computer, the integrity of
the TRUNK is of utmost importance. Any physical damage to the TRUNK cabling will cause the network
communications to cease past the break, effectively isolating that portion of the installation and stopping
communications with all of the equipment attached to the isolated portion.
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Nexus System Solutions
T1
T7
R7
T7
T6
R6
T6
T5
R5
T5
T4
R4
T4
T3
R3
T3
T2
R2
Branch line
T2
Key
SPU
Data cable
R# Router
Trunk
line
T# Terminator
Nexus server
T1
For example, a break occurring in the TRUNK cable between R2 and R3 would effectively isolate
CHANNELS 3 and up. The NEXUS Server would only be able to communicate with CHANNEL 2. The
break would need to be located and repaired before communications to the isolated portion could resume.
Therefore, when planning the route of the TRUNK (and any other cable), consider exactly where
the cable is to run and how it is to be installed to prevent damage at any time. Do not route data
cabling on top of removable ceiling tiles where the movement of the tile (during other building or
maintenance works) can damage it. Likewise, do not plan the route of the TRUNK through tenancy areas. If
that tenancy is changed at some time in the future, work could damage the TRUNK.
T&B recommends that the TRUNK cabling be run only in the common areas of buildings and installed
in such a way that accidental damage to the cabling be minimized. Most modern buildings have dedicated
communications cable trays, cabinets or risers for running the cables.
STEP
14
15
Mark the Trunk Route on the Plans
Draw the route of the TRUNK on your plans to link the NEXUS Server to every ROUTER in the same
manner and style as you chose to represent the CHANNEL DATA CABLE wiring. Remember to include
CHANNEL TERMINATORS at both ends of the TRUNK. They will be T1s.
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STEP Number the Channels
15
Using this knowledge of the NEXUS topology, we constructed the diagram below as the layout
of the sample building we used earlier in the guide.
T1
T4
R4
Second
floor
T4
Branch line channel 4
4-1
4-2
4-4
4-3
4-5
4-6
4-7
4-8 etc...(up to 4-50)
T3
R3
First
floor
T3
Branch line channel 3
3-1
3-2
3-4
3-3
3-5
3-6
3-7
3-8 etc...(up to 3-50)
T2
R2
T2
Branch line channel 2
2-1
2-2
2-4
2-3
2-5
2-6
Key
2-7
2-8 etc...(up to 2-50)
SPU
Data Cable
Nexus server
R# Router
T# Terminator
T1
ADMINISTRATION BUILDING
Ground Trunk line
floor
channel 1
In this example, the TRUNK originates at the NEXUS Server located in the Building Manager’s office on
the Ground Floor and runs through the Data Riser to allow a Router connection on and for each floor. Here
we have allocated a separate CHANNEL for each floor of the building. The TRUNK must be CHANNEL 1.
In this example, the CHANNELS are numbered sequentially from the NEXUS Server outwards. The first
branch CHANNEL nearest to the NEXUS Server called CHANNEL 2 serves the Ground Floor, CHANNEL 3
is for the Second Floor and so on. SPUs 2-1 to 2-50 are allocated to CHANNEL 2 on the Ground Floor,
SPUs 3-1 to 3-50 are allocated to CHANNEL 3 on the Second Floor, and so on.
T&B recommends that you allocate only 50 SPUs per CHANNEL for reasons stated earlier, and to make
installation, commissioning and maintenance easier.
Number the CHANNELS on your plans in sequential order from one end of the TRUNK to the other.
In fact, it is the logical choice as the TRUNK must be numbered CHANNEL 1, then the closest CHANNEL
to the end that branches off the TRUNK should be numbered 2, the next 3, and so on.
During the commissioning of the installation, the ROUTERS and SPUs will be programmed with their own
CHANNEL-coded ID numbers that tell them which CHANNEL they are connected to and which cannot
be changed without a recommissioning process.
If, in the future, an extra CHANNEL is added to the TRUNK (at a point somewhere between the CHANNELS
you have already sequentially numbered) the new CHANNEL must be given a different number than any
existing CHANNEL. So, in the future, the connected order may become out of numerical sequence.
No two CHANNEL numbers can be the same. The system will communicate with the CHANNELS by
their ID number, not their sequence. This feature of NEXUS allows for future alterations to the installation
without the need for major renumbering and recommissioning.
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If you know about future possible additions to the system, you can make allowances for that now by
reserving the proposed additional CHANNEL number. Skip to the next so that the eventual outcome will be a
connection order that matches the numerical sequence order of your plans.
Once you have numbered the CHANNELS, write the CHANNEL number in the space provided for previously
in the ROUTER and TERMINATOR symbol boxes on the plans.
They should look something like these:
R2 R3 R4
and
T1 T2
.
NOTE: There is no R1. Its job is done by the NEXUS Server, which is located where R1 would otherwise be.
Remember that there is one Router and two Terminators per CHANNEL, i.e. CHANNEL 2 will have R2, T2
and T2 connected to it; CHANNEL 3 will have R3, T3 and T3 and so on.
STEP
16
Create the Materials List
1. Cross reference the Installation list with the plan drawings to double check the data and totalize
the SPU type Catalogue number column to create a materials list of SPUs.
2. Count the number of CHANNELS and calculate the quantity of:
• CHANNEL TERMINATORS (2 per CHANNEL).
• ROUTERS (1 per CHANNEL).
• REPEATERS (1 per extended CHANNEL).
3. Include 1 PC package (as listed in NEXUS Technical Specifications) per NEXUS network.
4. Include the NEXUS software and adaptor card.
List all these items together in a specification materials list that would allow the potential installer to quote for
the supply of the equipment during the tendering stage of the project.
STEP
17
Create the Project Specifications
This is the end of the Design Stage. You should have completed the plan drawings showing the:
•
•
•
•
•
•
•
•
Location of the SPUs.
Individual Channel Sequence Number of every SPU.
CHANNEL routes.
ROUTER, REPEATER and TERMINATOR locations.
TRUNK route.
NEXUS Server location.
Distribution Board and Circuit Breaker details.
GROUP number of the SPUs if desired.
Also, specify the receptacles for the NEXUS Server and equipment, ROUTERS and REPEATERS.
You will also need to include the NEXUS Server and peripherals including furniture, if required.
• A sample emergency lighting specification is appended to this guide.
• Sample typical project designs are appended to this guide.
You can copy and include them in your tender documents.
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Designer checklist:
1. Maximum of 50 SPUs per Channel/Router.
2. Sequential numbering of SPUs (i.e. use of channel sequence numbers).
3. Maximum of 140 Channels.
4. Sequential numbering of Channels/Routers.
5. Obey Data Cable length restrictions for each Channel depending on the Data Cable type used (refer
to Select the Cable Size and Brand).
6. End-of-line Terminators must be at the beginning and end of each cable segment
and shown on the drawings.
7. Data Cable should be shown on drawings wherever possible.
8. Ensure NEXUS Server location is accessible and practical for both the Installer and End User.
You have now reached the end of the design stage. If you require any further assistance, call the T&B
Product Support Help Hotline.
STEP
18
Contractor (Installer) Requirements
This step specifies what the Designer needs the Installer to do.
1. Use sequential numbering of Routers as per the Trunk cable route.
2. Use sequential numbering of SPUs as per the Channel cable route (i.e. channel sequence number).
3. Enter all Router and SPU location and description information into the NEXUS Server database.
4. Provide complete as-installed drawings detailing Data Cable routes, Router locations,
SPU locations and all Router and SPU numbering.
5. Follow installation and commissioning procedures as described in NEXUS Installation Guide and
NEXUS Commissioning Guide.
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Nexus System Solutions
Sample Consultant Specification
Emergency Lighting Fixtures
The Fixtures shall be manufactured and installed in compliance with CSA141 C22.2. Each fixture shall
contain 3 x 8 bit microprocessors with two processors responsible for data communications to ensure
fast reliable data transfer rates.
The micro-controller in each emergency light fitting shall monitor and store the operation of:
• AC supply (on/off )
• Battery connection (charging/not charging)
• Battery charger (on/off )
• DC-AC inverter output (on/off )
• Emergency lamp light (on/off )
Each fitting shall store the result of its last discharge test in non-volatile memory that is retained even
after loss of both AC power and DC battery supply.
The system shall not require factory pre-programming of fixtures and the server on site shall issue them with
a Network address identification number during commissioning of the communication system.
Computer Hardware
Pentium III processor based PC (or better) with Windows 2000 Professional or XP Professional, with at least
256 MB RAM, 20 GB 7200 rpm HDD, CD-RW Drive, 1.4 MB FDD, 15" (or better) SVGA Monitor, 56 kpbs
Modem (or better), mouse and pad, one free internal PCI BUS slot, plus Inkjet/
Bubble Jet printer (or better) and paper. The network functionality and testing facilities are dependent upon
a PC being present.
Computer Software
The software shall:
• Be fully compatible with Windows 2000 or later.
• The system interface shall be a 32 bit graphical application capable of representing the network
topology on the screen.
• Allow addition, deletion or replacement fixtures without interfering with the rest of the network and
without the need to reprogram any other fixtures.
• Allow the end user to create and delete test groups and allow any fixtures to be moved to a test group
using standard Windows functions (Drag and Drop or Cut and Paste).
• Include a Maintenance Group that contains all faulty SPUs within the System.
• Contain a Maintenance logbook recording all discharge tests and system maintenance.
• Provide facility for location information to be entered into a database detailing all relevant information
for the Server, Routers and SPUs.
Communications
The communications system protocol shall be Echelon LonTalk™. Network communications shall be via
a multidrop bus topology using a single twisted pair, shielded data cable rated UL Level 4 (or better)
connected in an open-ended daisy-chain manner.
The network speed must be at least 78 kbps to ensure a fast and reliable network, capable of further
expansion. A complete status poll shall take no longer than one (1) second per fixture.
The Network shall be divided into segments (Channels) containing not more than 50 emergency light
fixtures. Each Channel shall be not more than 1000 m (3250 ft) in data cable length.
Each Channel shall be terminated with a Channel Terminator at each end and the location of the Channel
Terminators shall be within the last device nearest to each end of the Channel. Each channel shall be
segmented from the system backbone (Trunk) by the use of a router device.
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The Channel data cable must not have any “tee-offs”. It shall be one continuous segment that does not
require looping back to its other end. The Channel data cable shall connect to each emergency lighting
fixture and the Router in a daisy-chain manner.
A backbone/trunk cable system shall connect all the routers in a daisy-chain manner back to a front-end
controller/server.
System Programming/Commissioning
The installing electrician shall carry out commissioning of fixtures onto the Network Communication System.
Installation of the system shall be a four-stage process:
Stage 1
Design, specification and tendering.
Stage 2
Installation, wiring and data cabling testing.
Stage 3
Set up server and software, program fixtures onto the network, creating database,
practical completion.
Stage 4
End user operation training.
At the time of commissioning, all routers and emergency lighting fixtures are to be clearly labelled with
the network address assigned by the server.
All descriptive information required by the front-end software package is to be entered by the commissioning
contractor and saved in the system database for the system server, routers and emergency lighting fixtures.
Detailed "As Installed" drawings must be provided upon completion of the system installation providing
the following information:
• Location of the system server, routers and emergency lighting fixtures.
• Data cable installation routes and exact graphic detail of the data cable installation between the
routers and the server and the emergency lighting fixtures and the routers.
• All routers and emergency lighting fixtures must be labelled with the network address assigned
by the system sever and must match the label attached to the router or emergency lighting fixture.
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Sample Typical High-rise Layout
T8
T1
R8
Channel 8
Roof level
Plant room
Future
spare
Fire
T7
irs
sta
Channel 7
Fourth
floor
T7
R7
Channel 7
Third
floor
T6
R6
T6
Channel 6
Trunk
Second
floor
T5
R5
Channel 5
T5
First
floor
T4
R4
T4
Channel 4
Nexus server
Ground
floor
T1
EXIT
T2
R3
Channel 3
Carpark
level 3
T3
Future
spare
T3
Channel 3
Carpark
level 2
T2
T1
R2
Channel 2
Carpark
level 1
Here are some examples of the many different ways that Channels can be routed through a high-rise
building. Keep in mind that each Channel must use the same brand and type of cable throughout its length.
Every Channel must have a Terminator at both ends. The total number of SPUs can not exceed
50 per Channel.
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Sample Typical Shopping Centre Layout
Channel 3
T3
T3
T1
R2
R3
T5
R4
T4
T2
Tr
un
k
Channel 4
Channel 2
T4
T2
Channel 5
R7 R6 R5
T5
k
n
Tru
T8
T8
T7
T6
Channel 6
Channel 7
Nexus server
T6
k
un
Tr
Channel 8
T9
Channel 9
T9
T7
R6
R9
R10
Trunk
T10
T10
Channel 10
T1
Here are some examples of the many different ways that Channels can be routed through a Shopping
Centre. Keep in mind that each Channel must use the same brand and type of cable throughout its length.
Every Channel must have a Terminator at both ends. The total number of SPUs can not exceed
50 per Channel.
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NEXUS
INSTALLATION
SECTION
Everything you need to know
to fully plan and Install a
T&B NEXUS
Network Control System for buildings
• Pre-installation checklist and reminders.
• A description of NEXUS symbols.
• Step-by-step instructions for communication cable selection,
installation and testing.
• Detailed NEXUS installation requirements and procedures.
• A guide to selecting the correct communications cable.
• NEXUS commissioning preparation procedure.
Nexus System Solutions
Communications and Emergency Lighting
Computerized emergency lighting systems are a combination of a communications network system
and emergency lights distributed throughout a building. The network is used to communicate between
the emergency light fixtures and a centrally located controller, usually a computer. The network passes
messages both to and from the emergency fixtures. This may be to instruct the SPUs to do something
(such as turn on or off their emergency lamps) or for the SPUs to report their status to the controller
(such as whether their lamps are working).
These computerised emergency lighting systems can and do use a variety of means to communicate.
The most common, inexpensive and reliable method uses a dedicated communications cable wired between
every SPU and the controller. The method of communication within the network, called the protocol,
determines the way the communications cabling must be installed, connected and used.
Other manufacturers of emergency lighting systems use differing Communication Networks and/or
protocols. A T&B Nexus System therefore CAN NOT be combined with other “Brand” fixtures.
NEXUS Topology
NEXUS uses a multidrop bus topology consisting of a common main line (TRUNK) with side lines
(branches) hanging off it which looks something like that shown below.
Trunk line
T1
R2
T1
R4
R3
Nexus server
T2
Key
SPU
Data cable
R# Router
T3
T2
25
T# Terminator
T3
T4
T4
Branch line
Branch line
Branch line
channel # 2
channel # 3
channel # 4
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This can look something like a tree if you turn it on its side and hang branches off both sides of the TRUNK,
as shown below.
T1
T7
R7
T7
T6
R6
T6
T5
R5
T5
T4
R4
T4
T3
R3
T3
T2
Branch line
R2
T2
Key
SPU
Data cable
R# Router
T# Terminator
Trunk
line
Nexus server
T1
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Before You Begin
To install a T&B NEXUS System it is assumed that you have the designed plans and project specifications of
the proposed installation with you. You may have been given design specifications that state which cable type
you must use, or that detail may be left up to you, the installer. If the design of the installation has been left up
to you, then you should use the separate NEXUS DESIGN SECTION to design the installation before you
continue.
This guide will take you through the steps of installing a complete T&B NEXUS System. If you are experienced
with installing a NEXUS project, then simply use this guide as a reminder. If however, you are not experienced
in the proper methods of NEXUS installation, T&B suggests that you read this complete guide through before
you start the installation.
What You Will Need
27
This Installation Section:
Contains all of the installation procedure information.
Electrical knowledge:
You should know about electrical installations and National Electrical Code 2005.
Drafting experience:
You should be experienced in reading and interpreting plan drawings.
Project plans:
Marked-up floor plans of the layout of the proposed installation.
Installation db list:
Installation database information listings.
Materials list:
Detailing the quantities of materials required.
Project specifications:
Design details and specifications of the project.
Drawing equipment:
Facilities to mark up installed plans either by hand or by computer.
Consultant’s reference:
The tenant’s fit-out guide and consultant’s specifications
(if available and relevant).
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The NEXUS System
NEXUS System Specification
Emergency Lighting Fixtures
The Fixtures shall be manufactured and installed in compliance with CSA141 C22.2. Each fixture shall
contain 3 x 8 bit microprocessors with two processors responsible for data communications to ensure
fast reliable data transfer rates.
The micro-controller in each emergency light fitting shall monitor and store the operation of:
•
•
•
•
•
AC supply (on/off )
Battery connection (charging/not charging)
Battery charger (on/off )
DC-AC inverter output (on/off )
Emergency lamp light (on/off )
Each fitting shall store the result of its last discharge test in non-volatile memory that is retained even
after loss of both AC power and DC battery supply.
The system shall not require factory pre-programming of fixtures and the server on site shall issue them with
a Network address identification number during commissioning of the communication system.
Computer Hardware
Pentium III processor based PC (or better) with Windows 2000 Professional or XP Professional, with at least
256 MB RAM, 20 GB 7200 rpm HDD, CD-RW Drive, 1.4 MB FDD, 15" (or better) SVGA Monitor, 56 kpbs
Modem (or better), mouse and pad, one free internal PCI BUS slot, plus Inkjet / Bubble Jet printer (or better)
and paper. The network functionality and testing facilities are dependent upon a PC being present.
Computer Software
The software shall:
• Be fully compatible with Windows 2000 or later.
• The system interface shall be a 32 bit graphical application capable of representing the network
topology on the screen.
• Allow addition, deletion or displacement of fixtures without interfering with the rest of the network and
without the need to reprogram any other fixtures.
• Allow the end user to create and delete test groups and allow any fixtures to be moved to a test group
using standard Windows functions (Drag and Drop or Cut and Paste).
• Include a Maintenance Group that contains all faulty SPUs within the System.
• Contain a Maintenance logbook recording all discharge tests and system maintenance.
• Provide facility for location information to be entered into a database detailing all relevant information
for the Server, Routers and SPUs.
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Communications
The communications system protocol shall be Echelon LonTalk™. Network communications shall be via
a multi-drop bus topology using a single twisted pair shielded data cable rated UL Level 4 (or better)
connected in an open-ended daisy-chain manner.
The network speed must be at least 78 kbps to ensure a fast and reliable network, capable of further
expansion. A complete status poll shall take no longer than one (1) second per fixture.
The Network shall be divided into segments (Channels) containing not more than 50 emergency light
fixtures. Each Channel shall be not more than 1000 m (3250 ft) in data cable length.
Each Channel shall be terminated with a Channel Terminator at each end and the location of the Channel
Terminators shall be within the last device nearest to each end of the Channel. Each channel shall be
segmented from the system backbone (Trunk) by the use of a router device.
The Channel data cable must not have any ‘tee-offs’. It shall be one continuous segment that does not
require looping back to its other end. The Channel data cable shall connect to each emergency lighting
fixture and the Router in a daisy-chain manner.
A backbone/trunk cable system shall connect all the routers in a daisy-chain manner back to a front-end
controller/server.
System Programming/Commissioning
The installing electrician shall carry out commissioning of fixtures onto the Network Communication System.
Installation of the system shall be a four-stage process:
Stage 1
Design, specification and tendering.
Stage 2
Installation, wiring and data cabling testing.
Stage 3
Set up server and software, program fixtures onto the network, creating database,
practical completion.
Stage 4
End user operation training.
At the time of commissioning, all routers and emergency lighting fixtures are to be clearly labelled with
the network address assigned by the server.
All descriptive information required by the front-end software package is to be entered by the commissioning
contractor and saved in the system database for the system server, routers and emergency lighting fixtures.
Detailed "As Installed" drawings must be provided upon completion of the system installation providing
the following information:
• Location of the system server, routers and emergency lighting fixtures.
• Data cable installation routes and exact graphic detail of the data cable installation between the
routers and the server and the emergency lighting fixtures and the routers.
• All routers and emergency lighting fixtures must be labelled with the network address assigned
by the system sever and must match the label attached to the router or emergency lighting fixture.
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NEXUS System Components
The physical components that make up the NEXUS System are described in the following topics.
Single Point Units (SPUs)
The term for an emergency lighting fixture (unit) that stands alone and includes its own rechargeable battery
and charger equipment. When normal AC power fails, it turns on its emergency lamp until the power is
restored or the battery discharges.
The selection and placement of the SPUs is usually determined by the relevant building codes and
STANDARDS. The design plans should show their exact location and type.
Emergency fixtures/SPU are represented by the emergency lighting symbol
may be shown as
or
.
while directional exits
Single Point Unit (SPU) Types
•
Non-Maintained: use one or more lamps that do not normally light the surrounding area but are
used only for emergency lighting. The light output is on only when the power fails.
Switching Emergency Lighting
•
Unswitched Active: all SPUs must be connected to an Unswitched Active supply. The unswitched
supply is used to charge the battery and is monitored to determine the supply status.
Channels
A CHANNEL is a section of Level 4 (or better) data communications cable used as the physical transport
medium for data packets. Its length is limited to 1,000m (3,250ft), it is terminated at both ends with signal
TERMINATORS and it has a maximum of 60 NODES. T&B recommends only 50 SPUs per CHANNEL
to allow for future expansion.
If you cannot arrange less than 50 SPUs together, or the CHANNEL cable length will exceed the
recommended maximum, you must use a REPEATER in the CHANNEL to boost the signals. This allows you
to lengthen the CHANNEL wiring to have up to 100 SPUs on that CHANNEL. There can be only one
REPEATER per CHANNEL.
You can connect up to a maximum of 140 CHANNELS on NEXUS. Depending upon the type of CABLE
used; the maximum length of any CHANNEL is up to 300, 600 or 1000 metres. See Select the Cable Size
and Brand for more details.
The CHANNELS on your plans should be numbered in sequential order from one end of the TRUNK to the
other. The TRUNK must be numbered CHANNEL 1, then the closest CHANNEL to one end branching off the
TRUNK is numbered 2, the next 3, and so on.
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Channel Sequence Numbers
The Channel Sequence Number identifies each SPU as a function of its CHANNEL and its place on that
CHANNEL. For example, the first SPU on CHANNEL 2 will have a Channel Sequence Number of 2-1.
Channel Sequence Numbers can be skipped and reserved for later use. Additional SPU’s can be added
to the system at any time. Any additional SPU’s will be given the next available number from either the
sequential order, or one from the reserved list.
Trunk
CHANNEL 1 is the TRUNK, which provides the communications connection between the NEXUS Server
and every other CHANNEL, in a daisy-chain method. As network data passes through the TRUNK,
its installation is critical.
Any physical damage to the cabling will cause the network communications to cease past the break.
Consider where the cable will run and how it will be installed, to prevent damage.
T&B recommends that the TRUNK cabling be run in secure cabling areas within a building so that
accidental damage to the cabling is minimized. Most buildings now have dedicated communications
cable trays, cupboards and risers.
Routers
A ROUTER connects a CHANNEL to the TRUNK and selectively transfers data PACKETS, while boosting
the signal strength.
The ROUTER must be located where it can be readily accessed. As it requires a 120V 60Hz receptacle
connection, make sure that it is close to a power point (usually on the same circuit as service the local
SPU’s). T&B recommends that you locate ROUTERS in electrical, data or riser cabinets, at eye level, to
allow for ready access. ROUTERS are represented in the drawing by a box with a capital R and a
CHANNEL identification number in it, for example R2 R3 R4 .
NOTE: There is no R1 on the TRUNK. Its function is performed by the NEXUS Server (PC). Your ROUTER
numbering should start at two and will match the CHANNEL numbering, i.e. R2 is connected to and serves
CHANNEL 2, and so on.
Repeaters
A REPEATER connects two sections of a CHANNEL together to extend the length of the CHANNEL
where you require a cable run longer than that allowed, or must install between 50 and 100 SPUs. It
transfers all communications traffic from one segment of the CHANNEL to the other, amplifying and
repeating the information for the extended segment.
A REPEATER is like a ROUTER, except that it connects to the end of a CHANNEL to extend the length
of that CHANNEL. Both segments of the CHANNEL are regarded by NEXUS as having the same
CHANNEL number.
Each REPEATER requires its own 120V receptacle. The REPEATER should also be located
in a readily accessible and serviceable position.
A REPEATER is represented in the drawing by a box with Rpt in it, for example Rpt .
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Channel Terminators
A TERMINATOR is a small packaged Resistive/Capacitive (RC) printed circuit board that must be attached
to both ends of every CHANNEL including the TRUNK.
TERMINATORS are passive electronic devices that do not require a power source and do not usually
require servicing. However, their locations should be specified and recorded.
TERMINATORS are represented in the drawing by a box with a capital T and a CHANNEL identification
number in it, for example T 2 T 4 .
There will be two TERMINATORS with the same number on every CHANNEL, one at each end.
The TRUNK is CHANNEL 1 so it uses T1. T2 is connected to CHANNEL 2, and so on.
NEXUS Server (Personal Computer)
The NEXUS Server should be located close to the end user of a NEXUS System, usually in the office of the
Building Manager or Maintenance Manager. Do not locate it in an area that is hostile to electronic equipment
such as dusty, dirty, oily or humid areas, workshops, switch rooms, plant rooms, or near high traffic areas.
This can be shown on the drawing like this.
The NEXUS Server will require 2 twin 120V receptacles, a desk with enough space for the computer
and monitor, the printer and paper feeder and to spread out copies of the plans.
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Data Cable Types
•
•
•
•
•
•
•
•
•
•
DATA CABLES must be treated as communications cables and be physically protected from damage.
Communications cables must never be connected to the AC supply.
Different DATA CABLE types have different characteristics which are better suited to carrying different
frequencies.
The DATA CABLE types that are rated Underwriter Laboratories (UL) Level 4 (or better) have been
designed, tested, proven and recommended for operating over the frequency range that NEXUS uses.
Two main types of DATA CABLES can be used for the NEXUS System : either Shielded or Unshielded.
Both are Twisted Pair, UL rated Level 4 (or better) communication cables.
Use only the same cable type within a CHANNEL.
Use only the DATA CABLE types that are listed here. Other DATA CABLE types will not work properly
in this type of communications network and T&B (or their agents) will not commission improperly cabled
projects.
The gauge of the wire directly affects the permissible maximum length of the CHANNEL. The sheathing
of the cable directly affects where it can be run. Choose the appropriate cable for the situation in which it
is to be used.
If multicore cables are used, the unused conductors must be individually connected and insulated
continuously throughout the length of the CHANNEL. They are to be grounded at one point only,
at the ROUTER of that CHANNEL, to prevent earth loops and possible communications interference.
The conductors of the same pair must be used. Separate pairs must never be connected in parallel for
any reason.
All cables and wiring methods should conform with the revelant article of the National Electrical Code.
Unshielded cable
Unshielded cables are prone to picking up any extraneous electrical EMF-induced voltages and signals
(noise) which may interfere with proper data communications and therefore should only be installed where
there is a low risk of noise interference.
Shielded cable
Shielded cables are less prone to picking up noise when installed and terminated properly.
Shielded cables must be run for the whole length of a CHANNEL if:
• Any part of that CHANNEL could potentially pick up any noise.
• The DATA CABLE is run parallel with AC supply cables.
• The DATA CABLE passes through or near a magnetic field such as an electric motor or a radio room.
Select the Cable Size and Brand
If the DATA CABLE is to be run in the same enclosure or conduit as AC supply cables, then the DATA CABLE
insulation must be suitably rated, and the cable must be shielded.
Recommended DATA CABLE
DATA CABLE TYPE
UL/CSA
RATING (type)
Shielded Twisted Pair
CMG
FLAME RESISTANT
CSA
Plenum
BRAND
(reference only)
FT4
CMP FT6
CERCO AT-HOM29
Contact your nearest T&B office for the latest recommended type.
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MAX CHANNEL
LENGTH
1,000 (3250ft)
Nexus System Solutions
Sample Diagrams
Using this knowledge of NEXUS topology, the diagram below was constructed as a sample building profile
line diagram.
In this example, the TRUNK originates at the NEXUS server located in the Building Manager’s office
on the Ground Floor and runs through the Data Riser to allow a ROUTER connection on, and for, each floor.
Here a separate CHANNEL has been allocated for each floor of the building. The TRUNK must be
CHANNEL 1. In this example, the CHANNELS are numbered sequentially from the NEXUS Server
outwards. The first branch CHANNEL nearest to the NEXUS Server called CHANNEL 2 serves the Ground
Floor, CHANNEL 3 is for the First Floor and so on. SPUs 2-1 to 2-50 are allocated to CHANNEL 2 on the
Ground Floor, SPUs 3-1 to 3-50 are allocated to CHANNEL 3 on the Second Floor, and so on.
NOTE the use of Channel Sequence Numbers for the SPUs.
T1
T4
R4
Second
floor
T4
Branch line channel 4
4-1
4-2
4-4
4-3
4-5
4-6
4-7
4-8 etc...(up to 4-50)
T3
R3
First
floor
T3
Branch line channel 3
3-1
3-2
3-4
3-3
3-5
3-6
3-7
3-8 etc...(up to 3-50)
T2
R2
T2
Branch line channel 2
2-1
2-2
2-4
2-3
2-5
2-6
Key
2-7
2-8 etc...(up to 2-50)
SPU
Data Cable
Nexus server
R# Router
T# Terminator
T1
ADMINISTRATION BUILDING
Ground Trunk line
floor
channel 1
NOTE that there is no R1. The NEXUS server is located where R1 would otherwise be.
Remember that each CHANNEL has a ROUTER and two TERMINATORS (i.e. CHANNEL 2 will have
R2, T2 and T2 connected; CHANNEL 3 will have R3, T3 and T3 and so on).
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Sample Typical High-rise Layout
T8
T1
R8
Channel 8
Roof level
Plant room
Future
spare
Fire
T7
irs
sta
Channel 7
Fourth
floor
T7
R7
Channel 7
Third
floor
T6
R6
T6
Channel 6
Trunk
Second
floor
T5
R5
Channel 5
T5
First
floor
T4
R4
T4
Channel 4
Nexus server
Ground
floor
T1
EXIT
T2
R3
Channel 3
Carpark
level 3
T3
Future
spare
T3
Channel 3
Carpark
level 2
T2
T1
R2
Channel 2
Carpark
level 1
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Sample Typical Shopping Centre Layout
Channel 3
T3
T3
T1
R2
R3
T5
R4
T4
T2
Tr
un
k
Channel 4
Channel 2
T4
T2
Channel 5
R7 R6 R5
T5
k
n
Tru
T8
T8
T7
T6
Channel 6
Channel 7
Nexus server
T6
k
un
Tr
Channel 8
T9
Channel 9
T9
T7
R6
R9
R10
Trunk
T10
T10
Channel 10
T1
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Before you Install
Check the Plans and Specs
The plans should contain:
• Up to 50 SPU symbols per CHANNEL.
• Sequential Channel Sequence Numbers.
• Clear CHANNEL DATA CABLE routes.
• 2 TERMINATORS per CHANNEL.
• 1 ROUTER per CHANNEL.
• Clear TRUNK DATA CABLE route.
• 1 NEXUS server (PC) location.
You should also have an installation list with at least the first 7 columns filled in and a row for every SPU.
This list works in conjunction with the plan drawings and will be the start of the installation database.
SPU reference numbering aids this crosschecking procedure.
The installation list should contain:
• The SPU reference number.
• Plan name or number.
• Plan grid cross-referencing data.
• A location description of the SPUs, including the building name or number if there are more than one.
• The floor or level numbers if there are more than one.
• The area or zone if it has a name or a compass bearing if it does not.
• The SPU Catalogue number or fitting type.
• The electrical isolation details of the lighting circuit that the SPUs are to be connected to.
See the sample installation database list below:
CH
SEQ
#
SPU type/
DB
CB
Ch
Grp
#
#
#
#
LOCATION DESCRIPTION
DRAWING
Bldg
Level Area/Zone
Plan #
2-1
Admin
Gnd
West corridor near elevators
ABC123
C4
SFNXS10FP
2
12
2
2
2-2
Admin
Gnd
NW corner at Firestair 1
ABC123
B3
MQFNXS110M
2
12
2
2
2-3
Admin
Gnd
Inside Firestair 1
ABC123
B3
BTNXS218M
1
5
2
1
2-4
Admin
Gnd
Landing, Firestair 1
ABC123
B2
BTNXS218M
1
5
2
1
2-5
Admin
Gnd
NW corridor near Firestair 1
ABC123
C3
SFNXS10FP
1
12
2
2
2-6
Admin
Gnd
Centre of North corridor
ABC123
E3
SFNXS10FP
2
12
2
2
2-7
Admin
Gnd
NE corner of North and East
corridors
ABC123
G3
etc…
Legend:
DB distribution box
CB circuit breaker
Ch channel
Grid # Catalogue #
Grp group
A blank database information sheet is appended to this guide. Photocopy sheets as required.
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Installing the Cabling
Following are details of how to prepare and install the different types of cable that may be used in a NEXUS
System installation.
• When shielded cable is used, the shielding must be connected and terminated correctly.
• Using a shielded cable without correctly terminating the shielding will result in reduced perfomance of
the communications network. It creates unwanted harmonics within the DATA CABLE, which can
interfere with proper network communications.
• T&B (or their agents) will not commission incorrectly wired installations.
• The shielding must remain electrically continuous across the cable joins, yet electrically isolated
from the conductors and any other metalwork or potential grounding point throughout the length
of the DATA CABLE, except for the one point where it must be connected to ground at the ROUTER.
The TRUNK cable shielding must only be connected to ground at one point, nominally at ROUTER 2.
T&B recommends that shielded DATA CABLES be stripped and terminated in the following manner.
1. Strip back and remove the outer sheathing of the cable for approximately 30mm (1.2”) from the end
of the cable being careful not to nick, cut or damage any shielding or conductor insulation under the
sheathing.
2. The shielding must then be peeled back to the level of the outer sheathing and unravelled to allow it
to hang away from the cable to expose the inner insulated conductors. Then twist the shielding together
to form a third conductor for the cable which allows it to be connected to the shielding of the other cable
for continuous electrical conductivity of the shields.
20 mm (0.8")
20 mm
(0.4")
3. Pull the twisted shields backaway from the data conductors, being careful not to damage them, and
lay them parallel with the sheathing back down the cable away from the ends. Use electrical insulation
tape to wrap around the cables and the shielding as shown below to hold it in place. Make sure the tape
wraps completely around the cables and itself for a full 3 turns as less than 3 turns will unravel itself over
time. Cut off any excess shielding hanging out past the end of the tape.
3 layers of
insulation
tape over
twisted
shields
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4. Strip back and remove conductor insulation approximately 10mm (0.4”) from the end
of the cable to allow for termination. Then twist them into like coloured pairs.
3 layers of
insulation
tape over
twisted
shields
5. Wrap all of the exposed shielding with at least 3 layers of tape to provide adequate electrical insulation
and mechanical protection, as this is the final outer layer.
Another 3 layers
of insulation tape
over twisted and
bound shields
Terminating Data Cable
The brand and type of cable you are using will determine the colour of the insulation of the conductors. Twist
like colours together; i.e. black to black,or red to red and so on. If present, twist the shields together.
Terminate the data wires into their respective terminals as provided in the SPUs. There are only 2 data wires
and 2 data terminals. The data terminals are unpolarized, so it does not matter which wire pair goes into
which terminal.
It is most important to ensure that the individual conductors of the same cable do not come into electrical
contact with each other, with the shielding or with any metalwork.
If multicore cables are used:
• The unused conductors are to be individually connected and insulated continuously throughout
the CHANNEL.
• They are to be grounded at one point only at the ROUTER of that CHANNEL, to prevent ground loops
and possible communications interference.
• The conductors of the same pair must only be used.
• Separate pairs must never be connected in parallel for any reason.
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Grounding Shielded Cables
Shielded cable can introduce problems if the shielding itself is not properly terminated. The shielding must
be electrically continuous throughout the length of the CHANNEL and connected to ground at only one point
in the CHANNEL, at the ROUTER. If the CHANNEL contains a REPEATER, then the shielding must be
electrically continuous and bypass the REPEATER the same as the shielding connections at a SPU.
The shielding must not connect to ground at any point other than at the ROUTER, nominally ROUTER 2
(see below).
Ground
point
Continuous
electrical
connection
Shielded
twisted wire pair
ROUTER
SPU or
REPEATER
SPU or
REPEATER
Data Cabling Rules
• The NEXUS network DATA CABLE is connected to the data terminals of each SPU, in an unpolarised
parallel daisy-chain method.
• Every SPU should have only 2 DATA CABLES connected to it.
• The only NEXUS device that has one cable connected to it is the last unit on a CHANNEL, at which
point a CHANNEL TERMINATOR must be installed.
• ROUTERS and REPEATERS can have 2 to 4 cables connected to them, depending upon
the configuration of the installation and on whether a CHANNEL TERMINATOR is located there.
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Installing Routers (or Repeaters)
ROUTERS and REPEATERS should be located to allow for easy access for commissioning and future
maintenance. They should be installed in either electrical or data cabinets, mounted about arm-height (about
1.5m (5ft) above floor level), so they can be readily seen and accessed. Each ROUTER
(or REPEATER) requires its own AC receptacle, usually on the same circuit as the local emergency lighting
(so that it is not inadvertently turned off).
Each ROUTER requires two sets of DATA CABLES. One set is the local CHANNEL and the other set is
the TRUNK. In choosing the location of the ROUTER (or REPEATER) make allowance for the routing
and connections of these cables.
In a typical installation within a multi-storey building in which the TRUNK runs up a communications riser
and tees off at each floor, the ROUTER would be located adjacent to the riser cable tray, as shown below.
NOTE the cable access routes, the height of the ROUTER and the power point.
The TRUNK cables are to be clearly marked, and kept separate from the CHANNEL cables. The TRUNK
cables connect to the terminals labelled TRUNK. The CHANNEL cables connect to the terminals labelled
CHANNEL. Do not confuse them. If you are not sure which cables are which, trace them back to their origin
or use an Ohmmeter to identify them. DO NOT USE a HI-Pot tester. Label the cables appropriately and
connect them to the Router.
A REPEATER must be installed in the same manner as a ROUTER. It requires its own AC receptacle,
as for a ROUTER.
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NEXUS Router
On the underside of the unit, there are two data ports and two power sockets (see the right part of the
figure below). On the front of the unit, there are two terminator switches, two data test sockets, four LEDs
and a push button (see the middle part of the figure below). The unit is supplied with a plug pack power
supply, two data cable connector plugs, a DC power jumper lead and an external data cable terminator.
The label on the front of the unit is made of a material that can be written on. During commissioning
of the network, record the channel numbers on this label for later reference.
40.0
Mounting hole
Indicates power is connected
POWER
TRAFFIC
SERVICE
REQUEST
A
ON
OFF
131.0
230.0
SERVICE
TERMINATOR
CHANNEL
Shows flow of data and flashes each time a packet is
forwarded from one channel to the other
Switch to ON position when data port is at the end of cable.
Switch to OFF position when data cable loops in and out
of data port
TEST
B
ON
OFF
SERVICE
TERMINATOR
Write Channel number here during commissioning of network
CHANNEL
TEST
Tick appropriate box during commissioning of network
134.0
ROUTER
REPEATOR
DATA PORTS
B
A
ROUTER
REPEATOR
Figure 1
Figure 2
TRUNK IN
CHANNEL OUT
CHANNEL IN
CHANNEL OUT
POWER
9V 100mA as P No 32-22937
LOOP
IN
LOOP
OUT
+
Figure 3
Regardless of whether you are connecting ROUTERS or nodes to the twisted-pair data cable, all are wired
in parallel across the pair. The connection is polarity insensitive. The data connection to the router is made
using a 3-way connector plug for each data port. The centre pin in each corresponding socket is the ground,
the outer 2 pins are data. The four different types of connections that can be made with this connector plug
are shown on the next page.
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Example Router Connections:
Trunk
T
R
R
OFF
ON
DATA
GROUND
DATA
DATA
GROUND
DATA
R
DATA
GROUND
DATA
T
Nexus
server
one and only
grounding point
Terminator
OFF
TWISTED
GROUNDED
Shield
Data Cable
LOOPED
TWISTED
NOT GROUNDED
NOT GROUNDED
TWISTED
END
Terminator
Shield
Data Cable
Branch
OFF
TWISTED
GROUNDED
LOOPED
T
T
R
DATA
GROUND
DATA
R
T
Tru
nk
T
DATA
GROUND
DATA
Tru
nk
Branch
Terminator
Shield
Data Cable
ON
GROUNDED
LOOPED
The function of the cable shield is to reduce pick-up of electrostatic noise. If the shield is not correctly
installed, the shield can pick up more noise than if the shield was not there at all. The shield must be
electrically continuous throughout the length of the CHANNEL and be connected to ground at one point only,
at a ROUTER or REPEATER. Connection at more than one point will create a ground loop in the shield,
which can pick up noise.
Terminators
Every correctly wired channel or channel section can be viewed as a continuous length of data cable with
nodes distributed along its length. The two ends of every CHANNEL must each have a Terminator
connected to it.
ROUTERS have a terminator built into each data port that can be switched on or off as appropriate. Often, a
channel starts or finishes at a ROUTER or REPEATER in which case the built-in terminator for that port is
simply switched on. When a CHANNEL starts or finishes at any other type of node (that is, the ROUTER
is in the middle of that CHANNEL), then an external Terminator should be connected at this point. No more
than two terminators are to be connected to a channel to avoid excessive attenuation of data signals which
could result in loss of data.
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Repeaters
A REPEATER connects two sections of a CHANNEL together to extend the length of the CHANNEL.
This may be necessary where a cable run is to be longer than 1000m (3,250ft) or when more than 50 SPUs
(limit 100 SPUs) are to be connected to the same CHANNEL.
The REPEATER transfers and repeats all data packets from one section of the CHANNEL to the other and
boosts the signal strength in the process. It counts as 1 NODE on each section of the CHANNEL.
Following are examples of how ROUTERS and REPEATERS are placed in a NEXUS system.
Example Router/Repeater Configuration 1 (Trunk):
T
R2
R3
R4
R5
T
Nexus server
R5
R6
R7
R8
Rpt1
R5
R9
R10
Example Router/Repeater Configuration 2 (Trunk):
T
T
R2
R3
R5
R4
T
R6
Rpt1
T
R8
R7
R9
Nexus server
Example Router/Repeater Configuration 3 (Trunk):
T
R2
R3
R4
T
Nexus server
R5
R6
T
Rpt1
T
R7
R8
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Example Router/Repeater Configuration 4 (Trunk):
Example Router/Repeater Configuration 5 (Channel Branch):
Power Connection
Each unit is supplied with a 120VAC 3 pin input, 9VDC output plug pack power supply. The negative output
terminal is connected to the AC supply ground. The DC power plug should be connected to the power
socket marked as LOOP IN. When a number of ROUTERS are installed in the one spot they can be
supplied from the one power supply. Up to 5 ROUTERS can be supplied by one 02-NRAS001 Plug Pack.
Use the power jumper lead supplied with each router to connect LOOP OUT to LOOP IN for successive
ROUTERS.
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Connecting Emergency Lighting Fixtures to the Network
See instruction sheet inside of SPU box.
Initial Testing of Emergency Lighting Fixtures
It is the responsibility of the installer to conduct the initial discharge test as soon as possible after
connecting permanent supply to the emergency light. You will need to keep your own records of the initial
test. If the SPUs are not to be left permanently connected to the AC supply, the installer is then responsible
for conducting the initial the initial test when the SPUs are permanently connected to the AC supply. T&B
conducts the initial test during final commissioning as part of the system package provided the installer has
successfully completed the initial discharge test. T&B is not responsible for the initial discharge test
unless separately contracted.
WARNING:
• Continuously switching the AC supply on and off to the SPUs during the installation process
(for example, due to building works) will cause the SPUs to discharge and charge their batteries many
times over a short period. This may shorten the life of both the battery and the lamp/s.
• T&B does not recommend such practices, and may not honour any warranty on the life of the
batteries, when subjected to such harsh operating conditions.
• The SPUs are designed to be regularly discharge tested every month for 5 minutes and every year
for full discharge.
• Excessive discharge testing is an abuse of the fittings.
• It is the installer’s responsibility to ensure compliance with the NEC and Local Codes.
• The data terminals are unpolarized which means that it does not matter which wire goes into which
terminal as long as like coloured conductors are twisted together and connected to the same data
terminal. The other like-coloured conductors of the pairs are twisted together, and go into the other
data terminal.
Preparation for Commissioning
This section of the Installation Guide describes what you must complete prior to commissioning.
As part of the System Contract, T&B Customer Service provides on-site attendance to assist the installer
when the project is commissioned
Before calling T&B (or their authorized agent) for commissioning of the project, you must ensure that
the following steps have been taken and that you have all the information ready for data entry to
the NEXUS database. You should have:
• Completed and checked the accurate plan drawings showing the as-installed location of every SPU,
Router, Repeater, Channel cable route, Trunk cable route and NEXUS Server.
• Fully completed and printed the database installation information list.
• Successfully installed, connected, tested and repaired all communication cabling for Channels, Trunks,
and equipment as described in this guide.
Commissioning is the process of using the NEXUS Server to communicate with the SPUs over the network,
to register and log the SPU network address data into the NEXUS database on the NEXUS Server.
The installation and location description details are entered into the database to marry with the SPU data
to enable NEXUS users to quickly locate and identify any item that requires service or attention.
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The Commissioning process generally proceeds as follows:
• The SPUs have been installed and energized for at least 24 hours (to ensure an adequate battery
charge state).
• Each Channel has been installed and successfully communications wink-mode tested.
• The Trunk, Routers and Repeaters (if required) have been installed, energized and successfully
communications tested as per the instructions in this Installation Guide.
• The NEXUS Server is installed, connected and tested.
• The NEXUS hardware interface is installed, connected and tested.
• The NEXUS software program is installed, configured and tested.
• The SPUs are commissioned into the database.
• The installation details are entered into the database.
• NEXUS is tested as a System.
• NEXUS is ready for the next stage of the project, End User operation.
Data Cable Connection
Experience has shown that nearly all problems encountered with the operation of a NEXUS system are
caused by incorrect wiring of the data cable network. Incorrect cabling will lead to poor or no data
communications.
The most common causes of problems include:
• Wrong DATA CABLE type.
• Wrong wiring topology (e.g. a “T” or star connection made at a node).
• Incorrect use of terminators.
• Incorrect connection of cable shields.
• Intermittent joins due to loose connections.
• Intermittent joins due to over-tightened damaged connections.
• Data cable proximity to electromagnetic noise sources.
NEXUS Support
Congratulations, you have reached the end of the installation stage. A blank emergency lighting installation
database list is appended to this guide. You can copy and use it during installation.
If you require any further assistance, telephone the T&B Product Support Help Hotline as listed below.
PRODUCT SUPPORT HELP HOTLINE
Tel.: 1-888-552-6467 ext. 547
Fax: 1-888-867-1566
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APPENDIX I
Glossary of Terms
BITS PER SECOND (BPS)
The term used to describe the speed of data transfer in digital form from one location to another. Usually described
in units of thousands - Kilo (K), or millions - Mega (M).
CHANNEL
A section of LEVEL 4 (or better) data communication cable used as the physical transport medium for Packets
of data. Limited to no longer than 1 Km terminated at both ends with signal TERMINATORS and with a maximum of
60 NODES connected to it. More than that will overload the CHANNEL and degrade signal performance. T&B
recommends only 50 SPU’s (nodes) per CHANNEL to allow for future expansion to the installation.
CHANNEL SEQUENCE NUMBER
Identifies each fitting as a function of its CHANNEL and its place on that CHANNEL. For example, the first
fitting on CHANNEL 2 will have a Channel Sequence Number of 2-1.
DATA CABLE TYPE 4
A specially manufactured twisted pair communications cable. Designed to handle over 16 Mbps of high-speed data
over a cable distance of up to 90 metres. For the T&B NEXUS System, at 78 Kbps can handle distances up to
a maximum of one Kilometre (Km) of cable run per CHANNEL.
DATA CABLE NETWORK
The interconnection (networking) of many discrete components in many different locations with a common DATA
CABLE. For NEXUS, the NETWORK is connected using the ECHELON LONWorks distributed Network Control
System twisted pair cable multi-drop or tree-like, bus method composed of a TRUNK and CHANNELS.
ECHELON
The name of the corporation that developed the LONWorks communications networking and control system,
LONTalk protocol and Neuron Chips in conjunction with MOTOROLA.
ELECTROMOTIVE FORCE (EMF)
The term commonly used to describe electrical energy, usually as a pulsing magnetic radiating electrical field like
a radio wave. An EMF can be induced into an electrically isolated wire if a magnetic field passes through it. If a wire
is run parallel with an alternating current carrying cable, an EMF is induced into the wire. If a DATA CABLE is run
parallel with mains carrying cables, an EMF is induced in the DATA CABLE. This induced EMF could interfere with
the flow of the data packets. Also known as EMF.
EMERGENCY LIGHTING NODE (ELN)
The communications printed circuit board assembly that connects an ELN SPU to the DATA CABLE.
LIGHT EMITTING DIODE (LED)
Small electronic low level coloured light source that acts as a status indicator. Used in emergency lights to indicate
power connection, battery charging or data signalling.
LOCAL OPERATING NETWORK (LON)
The proprietary name used by ECHELON for their distributed control, Neuron based communications NETWORK.
LONTalk
The proprietary communications Network protocol created by ECHELON for embedded use in Neuron chips.
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LONWorks
The complete communications networking and control system including software, firmware, silicon and hardware
produced by ECHELON to enable third party development and use of ECHELON LON system products.
NETWORK CONTROL SYSTEM (NCS)
The T&B implementation of the LONWorks package developed to install, monitor and control the NETWORK
for the remote operation and monitoring of T&B intelligent emergency light fittings.
NEURON
The name given to the micro-controller silicon chip developed by ECHELON, manufactured by MOTOROLA
and TOSHIBA, that forms the basic component in every LON NODE. Each Neuron chip contains a permanent
world-wide unique 48 bit encoded Neuron identification number, 3 microprocessors each dedicated to a different
function, on board memory and built in Network communications ability with a common, message-based control
LONTalk protocol to process inputs from sensors and control devices intelligently.
NEXUS Server
The PC used to interface between the system and its user. The NEXUS PC consists of a STANDARD PC with
an internal Ziatech interface card or an external ECHELON Serial LONTalk adaptor connected to the T&B NEXUS
DATA CABLE NETWORK, for the operation and control of the NETWORK devices via the NEXUS Software.
Can be operated remotely via a modem. Used to send instructions to and to receive status from the NEXUS
NETWORK. Stores the database of fitting details, status, test results and logbook. Data can be viewed on screen,
saved to disk or printed if required.
NODE
The intelligent NETWORK device that connects to the NETWORK cable through 78 Kbps transformer isolated
transceivers and functions as a source or destination of PACKETS of communication data. Every NODE contains
a NEURON chip. This along with other software and firmware coded addresses, allows each NODE to be
contacted over the NETWORK, individually or in groups.
PACKET
A defined quantity of data transmitted on the NETWORK to LON specifications. Forms a complete message including
source and destination addresses with command instructions and data. All NETWORK data is in PACKETS.
POWER OUTLET
An enclosed assembly that may include receptacles, circuit breakers, fuse holders etc. to serve as a means
for distributing power required to operate mobile or temporarily installed equipment; Normally 120 volt 60Hz.
REPEATER
Connects two sections of a CHANNEL together to extend the length of a CHANNEL for the necessity of either a
cable run longer than 1Km, or to allow between 50 and 100 SPU’s to be connected to the same CHANNEL.
Transfers and repeats all data Packets from one section of the CHANNEL to the other and boosts the signal
strength in the process. Counts as 1 NODE on each section of the CHANNEL.
ROUTER
The device that connects a branch CHANNEL to the main TRUNK. Selectively transfers data PACKETS from one
CHANNEL to the other (and boosts the signal strength in the process), when the NETWORK destination address of
the PACKET lies on the other side of the ROUTER. The advantage of this device is that it reduces NETWORK
activity (traffic) because it only relays the data if the recipient or sender is located on its CHANNEL. All fittings
broadcast their data PACKET messages on their CHANNEL and the ROUTER rebroadcasts it onto the TRUNK.
Once there, all of the other ROUTERS can hear the message, but only the one that has the recipient on their
CHANNEL will relay it onto its separate CHANNEL.
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ROUTER / REPEATER TYPES
Near Side
If installed as a router the
near side is the trunk side
Tx
If installed as a repeater in
a channel/branch the near side
is the one closest to the router
Far Side
ROUTER
Near Side
If installed as a repeater in
the trunk the near side is the
one closest to the NEXUS Server
Tx
Tx
Far Side
REPEATER
If installed as a router the far side
is the channel/branch side
Tx
If installed as a repeater in a
channel/branchthe far side is
the one furthest from the router
If installed as a repeater in
the trunk the far side is the one
furthest from the NEXUS Server
Router / Repeater types:
Type
Near Side transmission speed
Far Side transmission speed
Standard Router
78kbps connected to
recommended copper data cable
78kbps connected to
recommended copper data cable
Standard Repeater
78kbps connected to
recommended copper data cable
78kbps connected to
recommended copper data cable
1.25Mbps Router
1.25Mbps connected to
recommended copper data cable
1.25Mbps connected to
recommended copper data cable
1.25Mbps Repeater
1.25Mbps connected to
recommended copper data cable
1.25Mbps connected to
recommended copper data cable
FTR Router
78kbps connected to
recommended copper data cable
Multimode Fibre optic cable
particular specifications
Etherlon Router
78kbps connected to
recommended copper data cable
Standard TCP/IP network
(Ethernet)
FTR Router / Repeater:
Contains fibre optic transceiver (FTR) and a standard 78kbps twisted pair copper transceiver. Can be configured as a router
or repeater with either fibre or copper transceivers connected as near side or far side.
Etherlon Repeater:
Contains Ethernet transceiver and a standard 78kbps twisted pair copper transceiver. Can be configured as a repeater with
either Ethernet or copper transceivers connected as near side or far side.
SINGLE POINT UNIT (SPU)
The term for an emergency light fixture (unit) that stands alone (at a single point) and includes its own rechargeable
battery and charger equipment. When normal AC power to it fails, it automatically energises its emergency lamp
until the power is restored or the battery discharges.
TERMINATOR
All small packaged Resistive/Capacitive (RC) printed circuit board (PCB) that must be attached to the very
ends of every CHANNEL in the DATA CABLE NETWORK. These ensure that the signals on the NETWORK
are not corrupted by unwanted reflections (noise) from transmission live discontinuities.
TRADEMARKS
All TRADEMARKS mentioned in this manual are the property of their respective owners.
NEXUS is the Trademark of Thomas & Betts.
ECHELON, LONWorks, LONTalk and Neuron are Trademarks of ECHELON Corporation.
MICROSOFT, MS-DOS, and WINDOWS are Trademarks of MICROSOFT Corporation.
WINK MODE
The data control method that causes the SPU LEDs to pulse alternating YELLOW-ORANGE/OFF. It is the mode
the NEXUS uses to check for correct NETWORK communications to indicate whether the SPU’s are receiving data.
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APPENDIX II
PROJECT:
CH
SEQ
#
DATE:
LOCATION DESCRIPTION
DRAWING
Bldg
Plan #
Level Area/Zone
SPU type/
Grid # Catalogue #
DB
CB
Ch
Grp
#
#
#
#
Sample
2-1
Legend:
Admin
Ground
DB
West corridor near elevators
Distribution box
CB
Circuit braker
ABC123
Ch
D-12
channel
SFNXS10
Grp
2
12
2
2
Group
Photocopy this blank sheet and use it to keep track of the NEXUS database information required for commissioning and database entry. A separate sheet
should be used for each channel; each sheet provides space for up to 50 SPU’s. T&B recommends a maximum of 50 SPU’s per Channel
or up to 100 per Channel where a REPEATER is used in accordance to page 19 NEXUS Installation Guide.
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APPENDIX III
SPU LED Colour Meanings
Every NEXUS SPU has a tricolour LED with the following possible states:
OFF
SPU not powered, or
Battery not charging, or
Lamp not present or failed
Still in last state when wink-mode stopped and SPU commissioned (press button or run
short test or turn power off and on to reset).
RED steady
Neuron chip power-up self-test result faulty.
RED pulsing (Red/Off)
SPU uncommissioned (unconfigured) and otherwise normal.
GREEN steady
SPU commissioned (configured),battery charging and lamp present. This is the normal
final working state.
GREEN pulsing (Green/Off)
SPU commissioned and under test.
YELLOW-ORANGE steady
SPU commissioned but still in previous wink-mode state
(press button or run short test or turn power off and on to reset).
YELLOW-ORANGE varying in intensity
SPU uncommissioned before wink-mode state. When wink is stopped, the LED is locked
on orange, with the uncommissioned pulsing RED in the background (press button or
run short test or turn power off and on to reset).
YELLOW-ORANGE
pulsing consistently @ _ second rate:
YELLOW-ORANGE / OFF pulsing
• Commissioned and under wink-mode command.
YELLOW-ORANGE / (RED or OFF) pulsing
• Uncommissioned and under wink-mode command . (Pulsing Red/Off
is normal uncommissioned state and pulsing YELLOW-ORANGE/Off is
wink-mode state, so both together will vary from YELLOW-ORANGE/Off
to YELLOW-ORANGE / (RED or OFF) depending on the different rates of pulse
and the times they overlap each other).
YELLOW-ORANGE
pulsing intermittently @
other than _ second rate:
Under wink-mode command and some network messages
are being lost.The possible causes of which are:
• The DATA CABLE is broken.
• The DATA CABLE has a short.
• The DATA CABLE is not termina ted properly at one of the devices.
• If shielded cable used, the shielding is not terminated properly.
• The CHANNEL cable is not termina ted properly at one or both ends.
• The CHANNEL cabling is incorrectly wired with a tee-off branch.
• The CHANNEL cabling is too long for the cable characteristics.
• There are too many SPUs in the CHANNEL.
• There is too much ‘noise’on the CHANNEL.
• One of the devices is faulty.
(YELLOW-ORANGE/
NOT YELLOW-ORANGE)
NOTE: To make the LEDs on the SPUs pulse YELLOW-ORANGE/Off in Wink-Mode a command is broadcast over the system every half
second to instruct the SPUs to change the state of their LED. If one of these instructions does not reach an SPU, then it will not make the LED
change on time and so will appear to either stay ‘on’ longer or stay ‘off’ longer than half a second. This could happen as regularly as every
alternate pulse or vary to only 1 in 10 pulses depending upon the number of network messages being lost and on the reason for the loss.
Unit Status According to LED colours
UNCOMMISSIONED
COMMISSIONED
NORMAL
RED /OFF pulsing
GREEN steady
UNDER TEST
N/A
GREEN/OFF pulsing
WINK MODE
YELLOW-ORANGE/(RED or OFF) pulsing
YELLOW-ORANGE/OFF pulsing
NEURON FAULTY
RED Steady
RED Steady
POWER FAILURE
OFF
OFF
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NEXUS Guide Feedback Sheet
T&B strives for excellence in product design, manufacture, quality and service. Should you have any comment to make
about this NEXUS Guide, or any other pertinent matter, we would like to hear from you. Please photocopy this page,
fill in your contact details, write your comments below, then either fax or post it to us. We need your feedback to assist
us in evaluating what we do, to see if we could do it better. Thank you.
Date:
To:
T&B
From:
Telephone:
Company:
Project:
Comments:
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NEXUS Support
If you require any further assistance, contact the T&B Product Support Help Hotline in Montreal as listed below.
Tel.: 1-888-552-6467 ext. 547
Fax: 1-888-867-1566
NEXUS DESIGN & INSTALLATION GUIDE
Please refer to your local building, electrical or fire authority for accurate municipal codes.
All informations and specifications contained in this guide are subject to change with out notice.
This Guide is part of a series of user-friendly guides to help you design, install, commissioning, maintain
and operate the NEXUS System.
Thomas & Betts Design & Installation Guide Nexus-E 06/06
54
Wherever you are, you can depend on Nexus
to get the job done!
What is NEXUS ? :
For Thomas & Betts, NEXUS is a real-time network management system for
emergency lighting and exit signs. It enables the user to manage the entire
installation – installing and removing components, testing and monitoring the
system and managing maintenance activities thus saving time and money on
maintenance.
MAKING YOUR LIFE EASIER AND YOUR BUILDING SAFER
Design & Installation Guide
Contact us:
Tel.: 1-888-552-6467 ext.: 547
Fax: 1-888-867-1566
distributed by
w w w . t n b - c a n a d a . c o m
© 2006. Thomas & Betts Limited. All rights reserved. Printed in Canada 06/06/150 Order no. NEXUSDESIGN&INSTALL.GUIDE-E
Leading the Way!!
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