Crestron Cresnet Network Guide

Cresnet® Network
Design Guide
Crestron Electronics, Inc.

Original Instructions
The U.S. English version of this document is the original instructions.
All other languages are a translation of the original instructions.
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Contents
Overview 1
Cresnet Device Definitions 2
Control Systems 2
Cresnet Servers 2
Cresnet Clients 2
Network Architecture 3
Maximum Network Size 3
Network Topologies 3
Home-Run Topology 3
Daisy-Chain Topology 3
Star-Network Topology 4
Cresnet ID Assignment 4
Client Device Distribution 6
Cresnet Distribution Blocks 6
Cresnet Distribution Block 6
Multitype Cresnet Distribution Block 7
DINRail Cresnet Distribution Block 8
Cresnet Hubs 9
Cresnet Hub 9
Din Rail Cresnet Hub 10
Ethernet-to-Cresnet Bridging 11
Ethernet-to-Cresnet Bridge with PoE 11
Ethernet-to-Cresnet Bridge for CAENAutomation Enclosures 12
Wiring and Connectors 14
Overview 14
Supported Cresnet Cables 15
Non-Plenum Cables 15
Plenum-Rated Cables 16
High-Power Cables 16
Data-Only Cables 17
Terminate Cresnet Wiring to a Connector 17
Best Practices 18
Power Requirements 20
Cresnet Power Calculator 20
Calculate Power Requirements for Wire Runs 21
Design Guide — Doc. 9292A Contents • iii

Wire Gauge Overview 21
Resistance Equation Formula 21
Example Scenarios 22
External Power Supplies 23
Appendix A:Troubleshoot Cresnet IDs 24
Insufficient Power 24
Incorrect Wire Gauge 24
Incorrect Wiring 24
Poor Wiring 25
Excessive Cresnet Clients 25
iv • Contents Design Guide — Doc. 9292A

Design Guide — Doc. 9292A Cresnet® Network • 1
Overview
The Cresnet™ communications protocol is designed for Crestron devices that do not require the
higher speeds of Ethernet. Cresnet provides a dependable and flexible wiring solution, allowing
multiple devices to be wired together in parallel using various network topologies. Asingle
Cresnet server can provide power and data to up to 25 client devices. Cresnet networks can be
further expanded using Cresnet hubs and Ethernet-to-Cresnet bridges.
This design guide provides the following information that can be referenced when designing a
Cresnet network system:
lOverview of Cresnet server and client devices
lOverview of Cresnet architecture
lCresnet device distribution options
lEthernet-to-Cresnet bridging options
lCresnet wiring and connector options and best practices
lCresnet power considerations
lCommon troubleshooting scenarios

2 • Cresnet® Network Design Guide — Doc. 9292A
Cresnet Device Definitions
A Cresnet network consists of three primary device categories:control systems, Cresnet servers
(masters) and Cresnet clients (slaves).
Control Systems
A control system supplies data to a combination of Cresnet clients, Cresnet distribution blocks,
or Cresnet hubs via its NET (Cresnet)port. Ethernet-to-Cresnet bridges can be added to a
Crestron control system to expand the size of the Cresnet network, creating isolated Cresnet
subnets that each behave as a Cresnet server with its own unique address space.
Certain Crestron control systems and Ethernet-to-Cresnet bridges also supply 24VDCpower to
Cresnet clients.
Cresnet Servers
A Cresnet server is a connection to a control system that allows a control system program to
communicate with Cresnet clients. A Cresnet server supplies power and data to Cresnet clients
via its built-in Cresnet bus. The Cresnet bus distributes bidirectional data communication and
24VDC power to each wired client device over a single 4-conductor cable.
Cresnet Clients
A Cresnet client receives its power and data from a Cresnet server either directly (wired to the
Cresnet server)or indirectly (wired to a Cresnet distribution block or hub or daisy-chained to
another Cresnet client). Cresnet clients each have their own specific power draw requirements
that must be taken into consideration when designing the Cresnet network.
Examples of Cresnet clients include keypads, lighting controls, shade motors, thermostats, and
occupancy sensors.

Design Guide — Doc. 9292A Cresnet® Network • 3
Network Architecture
The following sections provide information about the Cresnet network architecture that should
be taken into consideration when designing a Cresnet network.
Maximum Network Size
The maximum size of a Cresnet network is dependent on the system design:
lA single Cresnet server supports up to 25 client devices with a maximum aggregate cable
length of 1,500ft (457m).
lACresnet network can be expanded to contain up to 90 client devices using Cresnet hubs.
Cresnet hubs also allow for longer cable runs. For more information, refer to Cresnet Hubs
(on page9).
lACresnet network can be further expanded to contain over 90 client devices using
Ethernet-to-Cresnet bridges. For more information, refer to Ethernet-to-Cresnet Bridging
(on page11).
Network Topologies
Cresnet network systems can be designed using any of the following network topologies. A
topology should be chosen that best suits the needs of the particular Cresnet installation or
space.
Home-Run Topology
For home-run topologies, wiring is run from the Cresnet server to a single Cresnet client.
Adistribution block is typically used in home-run topologies to allow the Cresnet server to
provide power and data to multiple Cresnet clients from one central location in the room. For
more information, refer to Cresnet Distribution Blocks (on page6).
Daisy-Chain Topology
For daisy-chain topologies, wiring is run from the Cresnet server to a Cresnet client. For
subsequent Cresnet clients, wiring is either run from a second port on the prior Cresnet client, or
wires are doubled in the connector. This daisy chain can continue for up to 25 client devices or a
for total run of 1,500ft (457m).

4 • Cresnet® Network Design Guide — Doc. 9292A
Star-Network Topology
For star-network topologies, wiring is run from the Cresnet server to a Cresnet hub. Cresnet
clients are then branched off from the central hub. This topology is commonly used when a
Cresnet wiring run needs to be taken into a different room. A distribution block connected to the
hub can then be used to route power and data to Cresnet clients in the room. Several Cresnet
hubs can be used to distribute power and data to multiple distribution blocks that all branch off
from a single Cresnet server.
CAUTION:When designing a Cresnet network using the star-network topology, the design
must ensure that no loops are created within the system. All runs from the Cresnet server
must connect to Cresnet clients or hubs only. Awiring run must never return to the Cresnet
server.
Cresnet ID Assignment
Cresnet IDs (NETIDs)are unique identifiers given to Cresnet devices on a network (similar to
IPIDs) that allow for network communication between Cresnet clients and servers. NET IDs
should be assigned using the Network Device Tree View tool in Crestron Toolbox™ software. For
more information, refer to the Crestron Toolbox help file.
Some devices ship with default Cresnet IDs other than 03 or 01 to help streamline some
packaged systems or to facilitate adjustments by certain software wizard systems. For a partial
list of default Cresnet IDs, refer to Crestron Online Help article 1001590.
NOTE:Cresnet servers always have a NET IDof 02. Valid NET IDs for Cresnet clients are
03through FE(03 through 254 decimal).
Refer to the following best practices when assigning NETIDs:
lEnsure no duplicate NETIDs are assigned to Cresnet clients on a Cresnet network. Using
the Network Device Tree View tool in Crestron Toolbox software to assign NETIDs is
recommended to avoid duplicate IDs.
lNo more than 90 client devices should be present on a Cresnet network.

Design Guide — Doc. 9292A Cresnet® Network • 5
lCrestron recommends grouping NETIDs so that similar products on a Cresnet network
are grouped together within a NETIDrange. The following example shows how various
product types could be grouped using NETIDs:
NOTE:Grouping Cresnet IDs helps organizations to group Cresnet devices to align
with various organizational standards. There are no electrical or communication
advantages to grouping Cresnet IDs.
oThermostats:10 through 1F
oKeypads:20 through 4F
oTouch screens:50 through 6F
oLighting controls:70 through 9F
oOther products:A0 through BF

6 • Cresnet® Network Design Guide — Doc. 9292A
Client Device Distribution
ACresnet network system with a single Cresnet server can provide power and data to up to 25
client devices with a maximum cumulative wiring run of 1,500ft (457m). Cresnet networks can
be expanded via Cresnet distribution blocks and Cresnet hubs. Each device type and supported
models are described in the following sections.
Cresnet Distribution Blocks
Cresnet distribution blocks allow for multiple Cresnet wiring runs to be terminated to one central
location within a room. The Cresnet distribution block is connected to the Cresnet server and
distributes power and data from the server to all connected clients. Cresnet distribution blocks
are commonly used in home-run network topologies, but can also be used to power client devices
off of a central Cresnet hub.
The following Cresnet distribution blocks are available.
Cresnet Distribution Block
The CNTBLOCK is a parallel distribution block designed to facilitate the termination of multiple
Cresnet wiring runs in an equipment cabinet, closet, or beneath a table.
CNTBLOCK Cresnet Distribution Block
lDiagnostic LEDs indicate the presence of network power and data.
lEight 4-pin detachable black (5mm) terminal blocks are provided, grouped in two sets of
four.
lPower can be isolated between the two sets by removing an internal jumper.
lIncludes an integral mounting flange for mounting to a flat surface.

Design Guide — Doc. 9292A Cresnet® Network • 7
Multitype Cresnet Distribution Block
The C2N-HBLOCK is a parallel distribution block for the termination of multiple Cresnet cables.
Three different types of connectors are provided to accommodate all types of Cresnet wiring,
including standard 4-wire Cresnet cable, Cresnet High-Power (HP)cable, and RJ-11 modular
cables (legacy installations only).
C2N-HBLOCK Multitype Cresnet Distribution Block
lDiagnostic LEDs indicate the presence of network power and data.
lUp to three units may be rack mounted together using the optional CNXRMAK rack mount
kit (sold separately).
lIncludes an integral mounting flange for mounting to a flat surface.
CAUTION:Do not connect or daisy chain more than one power input (power pack or power
supply)to the C2N-HBLOCK. Connecting multiple power inputs may cause damage to the
power inputs.

8 • Cresnet® Network Design Guide — Doc. 9292A
DINRail Cresnet Distribution Block
The DIN-BLOCK is a DIN rail-mounted Cresnet distribution block designed to facilitate the
termination of Cresnet wiring at a head end or distribution point. DIN rail mounting enables
modular installation alongside Crestron DIN Rail lighting and automation control modules and
other third-party DIN rail mountable devices.
DIN-BLOCK DINRail Cresnet Distribution Block
lDiagnostic LEDs indicate the presence of network power and data.
lTwelve 4-pin detachable green (3.5mm)terminal blocks are provided, grouped in two sets
of six.
lProvides a split power bus for flexible 24V power distribution.

Design Guide — Doc. 9292A Cresnet® Network • 9
Cresnet Hubs
Cresnet hubs are designed to expand the size of a Cresnet network system to over 25 client
devices or 1,500ft (457m) of wire runs. Each Cresnet hub provides multiple isolated Cresnet
segments that each support an additional 25 client devices and 1,500ft (457m)of wire runs.
Multiple Cresnet hubs can be added to a Cresnet network system to allow for up to 90 powered
client devices. Cresnet hubs are used primarily within star-network network topologies where a
single Cresnet server must power client devices across multiple rooms or locations in a facility.
Cresnet Hub
The CNXHUB is a six-segment Cresnet hub designed for configuring large Cresnet networks. A
Cresnet hub is ordinarily required for any Cresnet network that has more than 25 devices or
1,500ft (457m) of cable.
CNXHUB Cresnet Hub
lDiagnostic LEDs indicate the presence of network activity for connected devices.
lFeatures six isolated Cresnet segments, each capable of supporting another 25 devices
with an additional aggregate run of 1,500ft (457m) of cable. More hubs can be added to
allow for a network of up to 90 devices.
lHoused in a compact metal enclosure that can be placed on a shelf, attached under a
table, or mounted in a 19in. equipment rack. Its 1 RU half-width form factor allows it to fit
in a single rack-space alongside a second CNXHUB or other 1RU half-width Crestron
device.

10 • Cresnet® Network Design Guide — Doc. 9292A
Din Rail Cresnet Hub
The DIN-HUB is a DIN rail-mounted Cresnet hub designed for configuring large Cresnet
networks. DIN rail mounting enables modular installation alongside Crestron DIN Rail lighting
and automation control modules and other third-party DIN rail mountable devices.
DIN-HUBDIN Rail Cresnet Hub
lDiagnostic LEDs indicate the presence of network activity for connected devices.
lFeatures three isolated Cresnet segments, each capable of supporting another 25 devices
with an additional aggregate run of 1,500ft (457m) of cable. More hubs can be added to
allow for a network of up to 90 devices.
lEach isolated segment supports up to 75 W of power to secondary devices.

Design Guide — Doc. 9292A Cresnet® Network • 11
Ethernet-to-Cresnet Bridging
Adding one or more Ethernet-to-Cresnet bridges to a Cresnet server distributes Cresnet over
high-speed Ethernet and allows for system sizes of over 90 Cresnet clients. The increased
bandwidth of Ethernet reduces latency for overall improved speed and performance. By
leveraging existing LAN infrastructure in a facility, wiring distances can be extended easily while
potentially reducing the overall wiring requirements. One or more bridges can be deployed on a
single Cresnet client, and they can be addressed by more than one control system.
The following Ethernet-to-Cresnet bridge devices are supported for expanding the size of a
Cresnet network over Ethernet.
Ethernet-to-Cresnet Bridge with PoE
The DIN-CENCN-2-POE works with any Cresnet server to maximize the reliability of a Cresnet
network. It offers a more robust solution than a Cresnet block or hub, providing two isolated
subnets and built-in diagnostics, plus versatile power distribution options and a convenient DIN
rail form factor.
NOTE:Crestron also provides a DIN-CENCN-2 Ethernet-to-Cresnet bridge that does not
supply any power over PoEor PoE+.
DIN-CENCN-2-POE Ethernet-to-Cresnet Bridge with PoE

12 • Cresnet® Network Design Guide — Doc. 9292A
lFeatures two isolated Cresnet subnets that each behave as a Cresnet server with its own
unique address space. Each subnet is capable of supporting 25 devices and provides six
connectors for terminating multiple wiring runs.
lOffers versatile power options:
o10 Wof power provided by PoE(Power over Ethernet) to both subnets, with up to
20 Wof power provided by PoE+.
o75 Wof power provided by external power supplies to one or both subnets
depending on the configuration.
lDiagnostic tools address many common Cresnet issues caused by wiring faults,
insufficient power, or too many client devices.
lProvides a TESTbutton on the front panel that can be pressed to generate error codes on
the LEDindicators. Complete details for each error code can be viewed in a web browser
or via Crestron Toolbox™ software.
Ethernet-to-Cresnet Bridge for
CAENAutomation Enclosures
The CAEN-BLOCK-CENCN-2-POE works with any Cresnet server to maximize the reliability of a
Cresnet network. The bridge can be mounted at the bottom of a CAEN,CAEN-MLO, or CAENIB
enclosure to provide a high-speed Ethernet interface between the enclosure and one or more
outboard Cresnet servers. It includes Cresnet and override connectivity for the CLX series
lighting control modules within the enclosure, and adds a separate isolated Cresnet subnet for
outboard Cresnet keypads, thermostats, sensors, and other Cresnet clients. It also allows those
Cresnet clients to be powered using a PoE, PoE+, or a 24VDC power source.

Design Guide — Doc. 9292A Cresnet® Network • 13
CAEN-BLOCK-CENCN-2-POE Ethernet-to-Cresnet Bridge for CAENAutomation Enclosures
lFeatures two isolated Cresnet subnets that each behave as a Cresnet server with its own
unique address space. Each subnet is capable of supporting 25 devices and provides six
connectors for terminating multiple wiring runs.
lOffers versatile power options:
o10 Wof power provided by PoE(Power over Ethernet) to both subnets, with up to
20 Wof power provided by PoE+.
o75 Wof power provided by external power supplies to one or both subnets
depending on the configuration.
lDiagnostic tools address many common Cresnet issues caused by wiring faults,
insufficient power, or too many client devices.
lProvides a TESTbutton on the front panel that can be pressed to generate error codes on
the LEDindicators. Complete details for each error code can be viewed in a web browser
or via Crestron Toolbox™ software.

14 • Cresnet® Network Design Guide — Doc. 9292A
Wiring and Connectors
The following sections provide information about Cresnet wiring and connectors within a
Cresnet network system.
NOTE:To view and download drawing packages that show common Cresnet wiring
scenarios, refer to Crestron Online Help article 1001565.
Overview
Observe the following about Cresnet wiring and connectors:
lAll wire is calculated in American Wire Gauge (AWG)sizes
lAll network wire must consist of two twisted pairs and a drain wire:
oOne twisted pair of 24VDCpower and ground (GND) conductors
oOne twisted pair of Y and Zdata conductors wrapped in a foil shield
oOne stranded jacketless conductor (for drain wire)
lStandard Cresnet wire uses the following specifications:
o18AWG(0.82mm2) red/black twisted pair is used for 24VDC power and ground.
o22AWG(0.33mm2) blue/white twisted pair is used for data (Yand Z) with
aluminum/polyester foil shield (providing 100%coverage)
o24AWG(0.20mm2) stranded tinned copper drain wire
lHigh-Powered (HP)Cresnet wire uses the following specifications:
o12AWG(3.31mm2) red/black twisted pair is used for 24VDC power and ground.
o22AWG(0.33mm2) blue/white twisted pair is used for data (Yand Z) with
aluminum/polyester foil shield (providing 100%coverage)
o24AWG(0.20mm2) stranded tinned copper drain wire
lCresnet cables are rated for low-voltage (60VAC/VDC or less) applications.
CAUTION:Cresnet cables should never be used within high-voltage (60VAC/VDC or
more) applications.
lThe following connectors are used by Cresnet-supported devices. Each connector type
supports wire termination for Cresnet power, data, and ground.
oBlack 4-pin terminal blocks with 5mm spacing
oGreen 4-pin terminal blocks with 3.5mm spacing
oRJ-11 style Cresnet distribution ports (legacy installations only)

Design Guide — Doc. 9292A Cresnet® Network • 15
Supported Cresnet Cables
The following Crestron cable types are supported for Cresnet wiring runs. Cables types should be
selected based on the Cresnet network installation requirements.
NOTE:For more information on determining the correct wire gauge to use for Cresnet
installations, refer to Calculate Power Requirements for Wire Runs (on page21).
Crestron Cresnet cables are compliant with the following regulatory standards:
lNECArticle 800
lUL®Subject 13, Type CM
lCSAType CMG
lRoHS
Non-Plenum Cables
CRESNET-NPseries cables are recommended for most standard Cresnet wiring runs.
CRESNET-NPseries cables contain one 18AWGpair for 24VDCand ground and one 22AWG
shielded twisted pair for control data within a non-plenum PVCjacket.
CRESNET-NPSeries Cable
lCRESNET-NP-BK-B500:Cresnet Control Cable, Non-Plenum, Black, 500ft (152m) box
lCRESNET-NP-OR-B500:Cresnet Control Cable, Non-Plenum, Orange, 500ft (152m) box
lCRESNET-NP-TL-B250:Cresnet Control Cable, Non-Plenum, Teal, 250ft (76m) box
lCRESNET-NP-TL-B500:Cresnet Control Cable, Non-Plenum, Teal, 500ft (152m) box
lCRESNET-NP-TL-SP500:Cresnet Control Cable, Non-Plenum, Teal, 500ft (152m) spool
lCRESNET-NP-TL-SP1000:Cresnet Control Cable, Non-Plenum, Teal, 1,000ft (304m)
spool
lCRESNET-NP-WH-B500:Cresnet Control Cable, Non-Plenum, White, 500ft (152m) box

16 • Cresnet® Network Design Guide — Doc. 9292A
Plenum-Rated Cables
CRESNET-Pseries cables are recommended for wiring runs within plenum spaces (such as air
ducts) or applications that require plenum-rated materials. CRESNET-Pseries cables contain
one 18AWG pair for 24VDC and ground and one 22AWG shielded twisted pair for control data
within a plenum-rated polymer jacket.
CRESNET-PSeries Cable
lCRESNET-P-BK-SP500:Cresnet Control Cable, Plenum-Rated, Black, 500ft (152m) spool
lCRESNET-P-OR-SP500:Cresnet Control Cable, Plenum-Rated, Orange, 500ft (152m)
spool
lCRESNET-P-TL-SP500:Cresnet Control Cable, Plenum-Rated, Teal, 500ft (152m) spool
lCRESNET-P-TL-SP1000:Cresnet Control Cable, Plenum-Rated, Teal, 1,000ft (304m)
spool
High-Power Cables
CRESNET-HPseries cables feature extra-large conductors for power and ground to support
devices that draw a large amount of power over a Cresnet bus. CRESNET-HPseries cables
contain one 12AWG pair for 24VDC and ground and one 22AWG shielded twisted pair for
control data within a non-plenum PVC jacket.
CRESNET-HPSeries Cable
lCRESNET-HP-NP-TL-SP500:Cresnet High-Power Control Cable, Non-Plenum, Teal,
500ft (152m)spool
lCRESNET-HP-NP-TL-SP1000:Cresnet High-Power Control Cable, Non-Plenum, Teal,
1,000ft (304m) spool