ELPRO 245U-E User manual

ELPRO, 9/12 Billabong Street, Stafford Q 4053, Australia.
Tel: [phone] Fax: [phone] Email: [e-mail]
Web: www.elprotech.com
ELPRO 24 hour Support Help-line America (866) 7134409 Rest of the world [phone]
User Manual
245U-E Wireless Ethernet & Device
Server

245U-E Wireless Ethernet User Manual
Page 2 Dec 2009
Thank you for your selection of the 245U-E Wireless Ethernet Modem. We trust it
will give you many years of valuable service.
ATTENTION!
Incorrect termination of supply wires may
cause internal damage and will void warranty.
To ensure your 245U-E enjoys a long life,
Double check ALL your connections with
the user’s manual
before turning the power on.
CAUTION:
To comply with FCC RF Exposure requirements in section 1.1310 of the FCC Rules, antennas used with this device
must be installed to provide a separation distance of at least 20 cm from all persons to satisfy RF exposure
compliance.
DO NOT:
•operate the transmitter when someone is within 20 cm of the antenna
•operate the transmitter unless all RF connectors are secure and any open connectors are properly terminated.
•operate the equipment near electrical blasting caps or in an explosive atmosphere
All equipment must be properly grounded for safe operations. All equipment should be serviced only by a qualified
technician.

Chapter One 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 3
FCC Notice:
This device complies with Part 15.247 of the FCC Rules.
Operation is subject to the following two conditions:
1) This device may not cause harmful interference and
2) This device must accept any interference received, including interference that may cause undesired operation.
This device must be operated as supplied by ELPRO Technologies. Any changes or modifications made to the device
without the written consent of ELPRO Technologies may void the user’s authority to operate the device.
End user products that have this device embedded must be installed by experienced radio and antenna personnel, or
supplied with non-standard antenna connectors, and antennas available from vendors specified by ELPRO. Please
contact ELPRO for end user antenna and connector recommendations.
Notices: Safety
Exposure to RF energy is an important safety consideration. The FCC has adopted a safety standard for human
exposure to radio frequency electromagnetic energy emitted by FCC regulated equipment as a result of its actions in
Docket 93-62 and OET Bulletin 65 Edition 97-01.
FCC Notice:
Part 15 – This device has been tested and found to comply with the limits for a Class B digital device, pursuant to
Part15 of the FCC rules (Code of Federal Regulations 47CFR Part 15). Operation is subject to the
condition that this device does not cause harmful interference.
Notice Any changes or modifications not expressly approved by ELPRO could void the user’s authority to
operate this equipment.
This Device should only be connected to PCs that are covered by either FCC DoC or are FCC certified.

245U-E Wireless Ethernet User Manual
Page 4 Dec 2009
Important Notice
ELPRO products are designed to be used in industrial environments, by experienced industrial engineering personnel
with adequate knowledge of safety design considerations.
ELPRO radio products are used on unprotected license-free radio bands with radio noise and interference. The
products are designed to operate in the presence of noise and interference, however in an extreme case, radio noise and
interference could cause product operation delays or operation failure. Like all industrial electronic products, ELPRO
products can fail in a variety of modes due to misuse, age, or malfunction. We recommend that users and designers
design systems using design techniques intended to prevent personal injury or damage during product operation, and
provide failure tolerant systems to prevent personal injury or damage in the event of product failure. Designers must
warn users of the equipment or systems if adequate protection against failure has not been included in the system
design. Designers must include this Important Notice in operating procedures and system manuals.
These products should not be used in non-industrial applications, or life-support systems, without consulting ELPRO
first.
1. A radio license is not required in some countries, provided the module is installed using the aerial and
equipment configuration described in the 245U-E Installation Guide. Check with your local distributor for
further information on regulations.
2. Operation is authorized by the radio frequency regulatory authority in your country on a non-protection basis.
Although all care is taken in the design of these units, there is no responsibility taken for sources of external
interference. Systems should be designed to be tolerant of these operational delays.
3. To avoid the risk of electrocution, the aerial, aerial cable, serial cables and all terminals of the 245U-E module
should be electrically protected. To provide maximum surge and lightning protection, the module should be
connected to a suitable earth and the aerial, aerial cable, serial cables and the module should be installed as
recommended in the Installation Guide.
4. To avoid accidents during maintenance or adjustment of remotely controlled equipment, all equipment should
be first disconnected from the 245U-E module during these adjustments. Equipment should carry clear
markings to indicate remote or automatic operation. E.g. "This equipment is remotely controlled and may
start without warning. Isolate at the switchboard before attempting adjustments."
5. The 245U-E module is not suitable for use in explosive environments without additional protection.
6. The 245U-E Operates using the same Radio frequencies and communication protocols as commercially
available off-the shelf equipment. If your system is not adequately secured, third parties may be able to gain
access to your data or gain control of your equipment via the radio link. Before deploying a system make sure
you have considered the security aspects of your installation carefully.

Chapter One 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 5
Limited Lifetime Warranty, Disclaimer and Limitation of Remedies
ELPRO products are warranted free from manufacturing defects for the “serviceable lifetime” of the product. The
“serviceable lifetime” is limited to the availability of electronic components. If the serviceable life is reached in less
than three years following the original purchase from ELPRO, ELPRO will replace the product with an equivalent
product if an equivalent product is available.
This warranty does not extend to the following:
- Failures caused by the operation of the equipment outside the particular product's specification, or
- Use of the module not in accordance with this User Manual, or
- Abuse, misuse, neglect or damage by external causes, or
-Repairs, alterations, modifications undertaken other than by an authorized Service Agent.
ELPRO liability under this warranty is limited to the replacement or repair of the product. This warranty is in lieu of
and exclusive of all other warranties. This warranty does not indemnify the purchaser of products for any
consequential claim for damages or loss of operations or profits and ELPRO is not liable for any consequential
damages or loss of operations or profits resulting from the use of these products. ELPRO is not liable for damages,
losses, costs, injury or harm incurred as a consequence of any representations, warranties or conditions made by ELPRO
or its representatives or by any other party, except as expressed solely in this document.
GNU Free Documentation Licence:
Copyright (C) 2009 ELPRO Technologies.
ELPRO Technologies is using a part of Free Software code under the GNU General Public License in operating the
“245U-E ” product. This General Public License applies to most of the Free Software Foundation’s code and to any
other program whose authors commit by using it. The Free Software is copyrighted by Free Software Foundation, Inc.
and the program is licensed “As is” without warranty of any kind. Users are free to contact Elpro Technologies at the
following Email Address: [email protected] for instructions on how to obtain the source code used in the “245U-
E”.
A copy of the license is included in the section entitled "GNU Free Documentation License".

245U-E Wireless Ethernet User Manual
Page 6 Dec 2009
CONTENTS
CHAPTER ONE INTRODUCTION..............................................................................................................8
1.1 NETWORK TOPOLOGY .......................................................................................................................................8
1.2 GETTING STARTED QUICKLY...........................................................................................................................11
CHAPTER TWO INSTALLATION.............................................................................................................12
2.0 GENERAL ................................................................................................................................................12
2.1 ANTENNA INSTALLATION........................................................................................................................12
Dual Antenna Installations...............................................................................................................................12
Line-of-sight installations................................................................................................................................13
Antennas..........................................................................................................................................................13
Installation tips.................................................................................................................................................13
Dipole and Collinear antennas.........................................................................................................................14
Directional antennas. .......................................................................................................................................14
2.2 POWER SUPPLY .......................................................................................................................................15
2.3 SERIAL CONNECTIONS ............................................................................................................................15
RS232 Serial Port ............................................................................................................................................15
DB9 Connector Pinouts...................................................................................................................................16
RS485 Serial Port ............................................................................................................................................16
2.4 DISCRETE (DIGITAL)INPUT/OUTPUT.......................................................................................................18
CHAPTER THREE OPERATION...............................................................................................................19
3.0 START-UP................................................................................................................................................19
“Access Point” Start-up (245U-E-G)...............................................................................................................19
“Access Point” Start-up (245U-E-A)...............................................................................................................19
“Client” Start-up..............................................................................................................................................19
Link Establishment..........................................................................................................................................19
How a Link connection is lost .........................................................................................................................19
Roaming Clients ..............................................................................................................................................20
LED Indication ................................................................................................................................................20
3.1 SELECTING A CHANNEL ..........................................................................................................................21
802.11b/g (2.4GHz).........................................................................................................................................21
802.11a (5GHz) ...............................................................................................................................................22
Dynamic Frequency Selection (DFS)..............................................................................................................22
3.2 CONFIGURING THE UNIT FOR THE FIRST TIME..........................................................................................23
Default Configuration......................................................................................................................................23
Accessing Configuration for the first time.......................................................................................................23
Method 1 - Set PC to same network as 245U-E ..............................................................................................23
Method 2 - Set 245U-E Network address to match the local network ............................................................25
3.3 NETWORK CONFIGURATION....................................................................................................................27
Network Settings Webpage Fields...................................................................................................................28
Security Menu..................................................................................................................................................29
3.4 NORMAL OPERATION..............................................................................................................................30
Transparent Bridge Operation .........................................................................................................................30
Router Operation .............................................................................................................................................31
3.5 RADIO CONFIGURATION.........................................................................................................................31
Channel Selection............................................................................................................................................33
Radio Throughput............................................................................................................................................33
Throughput and Repeaters...............................................................................................................................34
3.6 DHCP CLIENT CONFIGURATION ............................................................................................................34
3.7 DHCP SERVER CONFIGURATION ............................................................................................................34
3.8 DNS SERVER CONFIGURATION...............................................................................................................34
3.9 SPANNING TREE ALGORITHM /REDUNDANCY ........................................................................................35

Chapter One 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 7
3.10 COMPATIBILITY.......................................................................................................................................36
What Addresses are in a wireless Ethernet data frame? ..................................................................................36
Packets between AP and Client.......................................................................................................................36
3.11 MULTIPLE AP REPEATER MESH NETWORK.............................................................................................38
3.11.1 Example – Extending range using WDS ..............................................................................................39
3.11.2 Example - Roaming with WDS Access Points.....................................................................................40
3.11.3 Example – Adding Redundancy...........................................................................................................40
3.11.4 Example – WDS Routed Network........................................................................................................42
3.12 ROUTING RULES......................................................................................................................................45
3.13 WIRELESS MESSAGE FILTERING..............................................................................................................47
MAC Address Filter Configuration:................................................................................................................48
IP Address Filter Configuration:......................................................................................................................48
ARP Filter Configuration.................................................................................................................................49
3.14 SERIAL PORT CONFIGURATION ...............................................................................................................50
RS-232 PPP Server..........................................................................................................................................50
Serial Gateway.................................................................................................................................................51
Modbus TCP to RTU Gateway........................................................................................................................52
Serial Menu......................................................................................................................................................53
3.15 DIGITAL INPUT/OUTPUT..........................................................................................................................54
3.16 MODBUS I/O TRANSFER..........................................................................................................................54
3.17 MODULE INFORMATION CONFIGURATION...............................................................................................57
3.18 REMOTE CONFIGURATION.......................................................................................................................57
3.19 CONFIGURATION EXAMPLES ...................................................................................................................58
Setting a 245U-E to Factory Default Settings..................................................................................................58
Extending a wired network..............................................................................................................................58
Connecting two separate networks together....................................................................................................58
Extending range of a network with a Repeater hop.........................................................................................59
CHAPTER FOUR DIAGNOSTICS..............................................................................................................60
4.0 DIAGNOSTICS CHART..............................................................................................................................60
4.1 DIAGNOSTIC INFORMATION AVAILABLE.................................................................................................61
Connectivity.....................................................................................................................................................61
Statistics...........................................................................................................................................................62
Network Traffic Analysis ................................................................................................................................62
4.2 TESTING RADIO PATHS ...........................................................................................................................62
4.3 UTILITIES ................................................................................................................................................63
“Ping” ..............................................................................................................................................................63
”Ipconfig”........................................................................................................................................................65
”Route”............................................................................................................................................................65
CHAPTER FIVE SPECIFICATIONS ......................................................................................................67
APPENDIX A FIRMWARE UPGRADE................................................................................................69
APPENDIX B GLOSSARY...................................................................................................................70
APPENDIX C CHANNELS ..................................................................................................................74
APPENDIX D 802.11A TX POWER REGULATIONS..........................................................................76
APPENDIX E GNU FREE DOCUMENTATION LICENCE ...............................................................77

245U-E Wireless Ethernet User Manual
Page 8 Dec 2009
Chapter One INTRODUCTION
The 245U-E Industrial 802.11 Wireless Ethernet module provide wireless connections between Ethernet devices and/or
Ethernet wired networks (LAN’s). They each comply with their relevant IEEE 802.11 standard.
The 245U-E is available in a range of different models with different RF power and frequency options suitable for your
country’s local radio regulations.
245U-E-G 802.11 b/g 400mW max power
245U-E-A 802.11 a 400mW max power
The above models have the same functionality but use a different radio to communicate. The different radios do not
communicate with each other, e.g. a 245U-E-G will not communicate with a 245U-E-A. Only modules of the same
type are able to communicate wirelessly to each other.
Throughout this manual, any reference to “245U-E” refers to one of the above models.
The 245U-E-G model uses a 2.4GHz Direct Sequence Spread Spectrum (DSSS) wireless transceiver. Users pick a 20
MHz channel with 5 MHz channel spacing from the available 13 starting with the first channel centered on 2.412 GHz.
Some limitations depending on country, see Appendix C for channel selections.
Note that regulations in North America permit 11 x 2.4GHz channels and Europe permits 13 x 2.4GHz channels.
The 245U-E-A uses a 5 GHz Direct Sequence Spread Spectrum (DSSS) wireless transceiver and users must select
appropriate channel, transmit power, etc allowable in that country.
Please check with your ELPRO representative for the permitted channel usage in your country.
See Appendix C for channels selections.
The 245U-E unit also provides two serial connections as well as the Ethernet connections. It is possible to use all three
data connections concurrently, allowing the 245U-E to act as a Device Server. Wireless connections can be made
between serial devices and Ethernet devices. The 245U-E provides connection functionality between serial “Modbus
RTU” devices and Ethernet “Modbus TCP” devices. Appropriate driver applications will be required in the host
devices to handle other protocols.
The 245U-E has a standard RJ45 Ethernet connection which will operate at up to 100Mbit/sec. The module will
transmit the Ethernet messages on the wireless band at rates between 1 and 54 Mbit/sec & 6 and 54 Mbit/sec depending
on model, band, encryption methods and radio paths.
1.1 Network Topology
The 245U-E is an Ethernet device, and must be
configured as part of an Ethernet network. Each
245U-E must be configured as an:
“Access Point” or “Sta”, “Station”, Client”
Also needs to be configured as a:
“Bridge” or “Router”.
You can also connect to the 245U-E via a RS232
or RS485 serial port using serial server or PPP (point-to-point) protocol. PPP allows the 245U-E to connect serial
communications into the Ethernet network.

Chapter One 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 9
Access Point vs Client
The Access Point unit acts as the “wireless master” unit. The Access Point accepts and authorises links initiated but
client units, and controls the wireless communications.
Clients (Stations) are slave units and when connected to the Access Point becomes transparent ethernet link.
The first diagram shows a connection between two Ethernet
devices using 245U-E ethernet modems. In this example one
245U-E is configured as an Access Point and the other as a
Client - the Access Point can be connected.
The second diagram shows an existing LAN
being extended using 245U-E’s. In this
example, the Access Point should be
configured at the LAN end - although the
wireless link will still work if the Client is at
the LAN end.
An Access Point can connect to multiple Clients.
In this case, the Access Point should be the
“central” unit.
An Access Point could be used as a “Repeater”
unit to connect two 245U-E Clients, which do not
have direct reliable radio paths.
There is no “Special” repeater module, any 245U-
E can be a repeater and at the same time, can be
connected to an Ethernet devices or on a LAN
Multiple Access Points can be set-up in a “mesh”
network to provide multiple repeaters.
Ethernet Devices
Client
Access
Point
Client
Client
LAN

245U-E Wireless Ethernet User Manual
Page 10 Dec 2009
Client
Bridge
Access Point
Router
192.168.102.54
192.168.0.34
LAN A
192.168.102.17
192.168.102.53
LAN B
Bridge vs Router
Each 245U-E is configured with an IP address for the Ethernet side, and another for the wireless side.
A Bridge connects devices within the same
Ethernet network - for example, extending an
existing Ethernet LAN. For a Bridge, the IP
address for the wireless side is the same as the
Ethernet side.
A Router connects devices on different LAN’s.
The IP addresses for the Ethernet and wireless sides are
different. In this example, the wireless link is part of
LAN A, with the Client unit acting as a Router between
LAN A and LAN B.
Alternately, the Access Point could be configured as a Router - the wireless link is then part of LAN B.

Chapter One 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 11
If more than two routers are required within the same radio network, then routing rules may need to be configured (refer
section “3.13 Routing Rules” for further details). There is no limit to the number of Bridges in the same network - although
there is a limit of 128 Client units linked to any one Access Point.
1.2 Getting Started Quickly
Most applications for the 245U-E require little configuration. The 245U-E has many sophisticated features, however if
you don’t require these features, this section will allow you to configure the units quickly.
First, read Chapter 2, “Installation”. The 245U-E requires an antenna and a power supply.
Power the 245U-E and make an Ethernet connection to your PC (for further information on how to do this, refer to
section 3.2 “Configuring the Unit for the first time”)
Set the 245U-E address settings as per section 3.2 “Configuring the Unit for the first time”
Save the configuration - the 245U-E is now ready to use.
Before installing the 245U-E, bench test the system. It is a lot easier to locate problems when the equipment is all
together.
There are other configuration settings, which may or may not improve the operation of the system. For details on these
settings, refer to section 3.0 “Start-up”.
LAN C
Client
Router
Access Point
Bridge
LAN A
Client
Router
Client
Bridge
LAN B
192.168.0.34
192.168.109.40
192.168.102.17
192.168.0.72
192.168.0.34
192.168.0.72
192.168.0.73
192.168.0.74

245U-E Wireless Ethernet User Manual
Page 12 Dec 2009
Chapter Two INSTALLATION
2.0 General
The 245U-E modules are housed in a rugged aluminium case, suitable for DIN-rail mounting. Terminals will accept
wires up to 2.5 mm2(12 gauge) in size.
All connections to the module must be SELV (Safety Extra Low Voltage). Normal 110-250V mains supply must
not be connected to any terminal of the 245U-E module. Refer to Section 2.3 Power Supply.
Before installing a new system, it is preferable to bench test the complete system. Configuration problems are easier to
recognize when the system units are adjacent. Following installation, the most common problem is poor
communications caused by incorrectly installed antennas, or radio interference on the same channel, or the radio path
being inadequate. If the radio path is a problem (i.e. path too long, or obstructed), a higher performance antennas or a
higher mounting point for the antenna may rectify the problem. Alternately, use an intermediate 245U-E Module as a
repeater.
The 245U-E Installation Guide provides an installation drawing appropriate to most applications. Further information
is detailed below.
Each 245U-E module should be effectively earthed via the "GND" terminal on the back of the module - this is to
ensure that the surge protection circuits inside are effective.
2.1 Antenna Installation
The 245U-E module will operate reliably over large distances however the achievable distances will vary with the
application, radio model, type and location of antennas, the degree of radio interference, and obstructions (such as
buildings or trees) to the radio path.
The maximum range achievable depends on the radio model, the regulated RF power permitted in your country, and
whether you use separate transmit and receive antennas.
•If using a 245U-E-G (2.4GHz) with a single antenna, 10 km (6 miles) can be achieved in USA, Canada and
Australia (4W EIRP) and 2km in Europe (100mW EIRP).
•If using a 245U-E-A (5 GHz) with a single antenna, 5 km (3 miles) can be achieved in USA, Canada and
Australia (1W EIRP) and 3km in Europe (500mW EIRP) however more care is needed in selecting antenna’s,
coax as well as radio paths need to be complete line of site (No obstruction what so ever).
To achieve the maximum transmission distance, the antennas should be raised above intermediate obstructions so the
radio path is true “line of sight”. The modules will operate reliably with some obstruction of the radio path, although
the reliable distance will be reduced. Obstructions which are close to either antenna will have more of a blocking affect
than obstructions in the middle of the radio path.
The 245U-E modules provide a diagnostic feature which displays the radio signal strength of transmissions (refer
Chapter 4 “Diagnostics”).
Line-of-sight paths are only necessary to obtain the maximum range. Obstructions will reduce the range, however may
not prevent a reliable path. A larger amount of obstruction can be tolerated for shorter distances. For short distances, it
is possible to mount the antennas inside buildings. An obstructed path requires testing to determine if the path will be
reliable - refer the section 6 of this manual.
Where it is not possible to achieve reliable communications between two 245U-E modules, then a third 245U-E
module may be used to receive the message and re-transmit it. This module is referred to as a repeater. This module
may also have a host device connected to it.
The 245U-E unit has two antenna connections at the top of the module, allowing for two antennas to be fitted to the
module. The left connector (looking at the front) labeled “RX” by default is connected only to the internal wireless
receiver and the right connector labeled TX/RX is connected to both the transmitter and receiver (**Note).
Note: Each antenna port has the option to enable /disable the Receive and Transmit
functionality by selecting Receive and Transmit Diversity on the radio page. When only one
antenna is used, it must be connected to the TX/RX connector.
Dual Antenna Installations
Most installations in industrial plants and factories use single omni-directional antennas. Installations can suffer from “

Chapter Two 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 13
multi-path fading” effects where multiple reflected radio signals adversely affect the signal strength. This can be
checked by moving the antenna a short distance (10 cm or 4 inches) - if the signal increases significantly then there are
multi-path effects.
In a “static” installation, where the radio path is not changing, moving an antenna to the position of maximum signal
solves this problem. However where the radio path changes because the 245U-E is mounted on moving equipment, or
if there is moving equipment in the area, then the solution is to use two antennas. Because the two connectors are
separated, the RF signal at each connector will be different in the presence of multi-path fading. The 245U-E unit will
automatically select the higher RF signal provided RX diversity has been enabled on radio config page.
Note that directional antennas are not normally used in plant and factory installations.
Another reason for using dual antenna is to improve the receiver gain. All countries have a limit on the amount of
transmitted power (from the module) and radiated power (from the antenna). In the US this is 1 Watt Transmit power
and 4 watts EIRP (Effective Isotropic Radiated Power)
A general rule of thumb when working with dB and Power is to remember that doubling the Power is a 3dB gain.
Therefore if we add a 6dB gain antenna to the 1 Watt transmitter we can boost the EIRP to 4 Watts (1 watt
Line-of-sight installations
In longer line-of-sight installations, the range may be increased by using a high gain antenna on the TX/RX connector.
However, the gain should not cause the effective radiated power (ERP) to exceed the permitted value. A second higher
gain antenna can be connected to the RX connector without affecting ERP - this will increase the operating range
provided any interference in the direction of the link is low.
Antennas
Antennas can be either connected directly to the module connectors or connected via 50 ohm coaxial cable (e.g. RG58
Cellfoil or RG213) terminated with a male SMA coaxial connector. The higher the antenna is mounted, the greater the
transmission range will be, however as the length of coaxial cable increases so do cable losses.
The net gain of an antenna/cable configuration is the gain of the antenna (in dBi) less the loss in the coaxial cable (in
dB). The maximum net gain of the antenna/cable configuration connected to the TX/RX connector is 0dB in Europe
(100mW ERP). In USA, Canada and Australia (4W ERP), the maximum gain is 10dB for the 245U-E-400 or 16dB for
the 245U-E-100. There is no gain restriction for antennas connected to the RX connector.
(*) 20dB attenuator must be fitted if radio distance is less than 33ft (10m).
Antenna 245U-E-G Gain (dBi) 245U-E-A Gain (dBi)
Dipole 2 dBi 6 dBi
Collinear 5 or 10 dBi 10 dBi
Directional 18 dBi 10 – 20 dBi
Cable Loss dB per 30 m / 100 ft dB per 30 m / 100 ft
RG58 Cellfoil -17 dB -24.5 dB
RG213 -16.2 dB -28.6 dB
LDF4-50 -3.6 dB -5.5 dB
The net gain of the antenna/cable configuration is determined by adding the antenna gain and the cable loss.
For example, if using the 245U-E-G a 10dBi antenna (7.8dBd) with 10 meters of
Cellfoil (-5.6dB) has a net gain of 2.2dB (7.8dB – 5.6dB).
Installation tips
Connections between the antenna and coaxial cable should be carefully taped to
prevent ingress of moisture. Moisture ingress in the coaxial cable is a common cause
for problems with radio systems, as it greatly increases the radio losses. We
recommend that the connection be taped, firstly with a layer of PVC Tape, then with
a vulcanizing tape such as “3M 23 tape”, and finally with another layer of PVC UV
Stabilized insulating tape. The first layer of tape allows the joint to be easily
inspected when trouble shooting as the vulcanizing seal can be easily removed.
Where antennas are mounted on elevated masts, the masts should be effectively
earthed to avoid lightning surges. For high lightning risk areas, surge suppression

245U-E Wireless Ethernet User Manual
Page 14 Dec 2009
devices between the module and the antenna are recommended. If the antenna is not already shielded from lightning
strike by an adjacent earthed structure, a lightning rod may be installed above the antenna to provide shielding.
Dipole and Collinear antennas
A dipole or collinear antenna transmits the same amount of radio power in all directions - as such that are easy to
install and use. The dipole antenna with integral 15 ft (5m) cable does not require any additional coaxial cable;
however a cable must be used with the collinear antennas.
Collinear and dipole antennas should be mounted vertically, preferably 1 wavelength away (see drawing below for
distances) from a wall or mast and at least 3ft (1m) from the radio module to obtain maximum range.
Directional antennas.
Directional antennas can be
a Yagi antenna with a main beam and orthogonal elements, or
a directional radome, which is cylindrical in shape, or
a parabolic antenna.
A directional antenna provides high gain in the forward direction, but lower gain in other directions. This may be used
to compensate for coaxial cable loss for installations with marginal radio path.
Yagi antennas should be installed with the main beam horizontal, pointing in the forward direction. If the Yagi is
transmitting to a vertically mounted omni-directional antenna, then the Yagi elements should be vertical. If the Yagi is
transmitting to another Yagi, then the elements at each end of the wireless link need to in the same plane (horizontal or
vertical).
Directional radomes should be installed with the central beam horizontal and must be pointed exactly in the direction of
transmission to benefit from the gain of the antenna. Parabolic antennas should be mounted as per the manufacturer’s
instructions, with the parabolic grid at the “back” and the radiating element pointing in the direction of the
transmission.
Ensure that the antenna mounting bracket is well connected to “ground/earth”.
Directional
Antenna
45
o
Wavelengths
900 MHz = 330 mm (1')
2.4 GHz = 130 mm (5")
5 GHz = 60 mm (3") COLINEAR
ANTENNA
MAST
IF GROUND CONDITIONS
ARE POOR, INSTALL MORE
THAN ONE STAKE
MODEM
SURGE
ARRESTOR
(OPTIONAL) COAXIAL CABLE
WEATHERPROOF
CONNECTORS WITH
“3M 23” TAPE
STRESS RELIEF
LOOP
PROVIDE GOOD GROUND
CONNECTION TO MAST,
MODULE AND SURGE
ARRESTOR
GND
1 wavelength

Chapter Two 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 15
+
_
B
A
-
+
COM
DIO
MODEM
9 - 30
VDC
RS485
SUPPLY
2.2 Power Supply
The 245U-E module can be powered from a 9 - 30VDC power supply. The
power supply should be rated at 1 Amp. The positive
side of the supply must not be connected to earth. The
supply negative is connected to the unit case
internally. The DC supply may be a floating
supply or negatively grounded.
The power requirements of the 245U-E unit are shown in the following table
245U-E-G 245U-E-A
12VDC 24VDC 12VDC 24VDC
Quiescent 290mA 150mA 300mA 160mA
TX @100mW 310mA 170mA 370mA 190mA
TX @ 400mW 340mA 180mA 410mA 210mA
A Ground Terminal is provided on the back of the module. This Terminal should be connected to the Main Ground
point of the installation in order to provide efficient surge protection for the module (refer to the Installation Diagram)
2.3 Serial Connections
RS232 Serial Port
The serial port is a 9 pin DB9 female and provides for connection to a host device as well as a PC terminal for
configuration, field testing and for factory testing. Communication is via standard RS232 signals. The 245U-E is
configured as DCE equipment with the pinouts detailed below.
Hardware handshaking using the CTS/RTS lines is provided. The CTS/RTS lines may be used to reflect the status of
the local unit’s input buffer. The 245U-E does not support XON/XOFF.
Example cable drawings for connection to a DTE host (a PC) or another DCE hosts (or modem) are detailed above.
DCE HOST
DB9
MALE
MODEM
DB9
MALE
RD
TD
SG
RTS
CTS
DSR
DTR
DCD
RD
TD
SG
RTS
CTS
DSR
DTR
DCD
2
5
7
8
6
4
1
3
2
5
7
8
6
4
1
3
DCE HOSTMODEM
DB9
MALE
DB9
FEMALE
RD
TD
SG
RTS
CTS
DSR
DTR
DCD
RD
TD
SG
RTS
CTS
DSR
DTR
DCD
2
5
7
8
6
4
1
3
2
5
7
8
6
4
1
3

245U-E Wireless Ethernet User Manual
Page 16 Dec 2009
DB9 Connector Pinouts
Pin Name Direction Function
1 DCD Out Data carrier detect
2 RD Out Transmit Data – Serial Data Output (from DCE to DTE)
3 TD In Receive Data – Serial Data Input (from DTE to DCE)
4 DTR In Data Terminal Ready
5 SG Signal Ground
6 DSR Out Data Set Ready - always high when unit is powered on.
7 RTS In Request to Send
8 CTS Out Clear to send
9 RI Ring indicator
RS485 Serial Port
The RS485 port provides for communication between the 245U-E unit and its host device using a multi-drop cable. Up to
32 devices may be connected in each multi-drop network.
As the RS485 communication medium is shared, only one of the units on the RS485 cable may send data at any one
time. Thus, communication protocols based on the RS-485 standard require some type of arbitration.
RS485 is a balanced, differential standard but it is recommended that shielded, twisted pair cable be used to
interconnect modules to reduce potential RFI. It is important to maintain the polarity of the two RS485 wires. An
RS485 network should be wired as indicated in the diagram below and terminated at each end of the network with a
120-ohm resistor. On-board 120-ohm resistors are provided and may be engaged by operating the single DIP switch in
the end plate next to the RS485 terminals. The DIP switch should be in the “1” or “on” position to connect the resistor.
If the module is not at one end of the RS485 cable, the switch should be off.
Shorter runs of 485 cable may not require the termination resistors to be enabled.
HOST MODEM HOST
RS485 CONNECTIONS

Chapter Two 245U-E Wireless Ethernet
Man_245UE_V1.5.doc Page 17
DIP SWITCH FOR 120Ω
DIO
SUPPLY
RS485
RS232
ETHERNET
DEFAULT DIP SWITCH

245U-E Wireless Ethernet User Manual
Page 18 Dec 2009
2.4 Discrete (Digital) Input/Output
The 245U-E has one on-board discrete/digital I/O channel. This channel can act as either a discrete input or discrete
output. It can be monitored, or set remotely, or alternatively used to output a communications alarm status.
If used as an “input”, the I/O channel is suitable for voltage free contacts (such as mechanical switches) or NPN
transistor devices (such as electronic proximity switches). PNP transistor devices are not suitable. Contact wetting
current of approximately 5mA is provided to maintain reliable operation of driving relays.
The digital input is connected between the "DIO" terminal and common “COM". The I/O circuit includes a LED
indicator which is lit GREEN when the digital input is active, that is, when the input circuit is closed. Provided the
resistance of the switching device is less than 200 ohms, the device will be able to activate the digital input.
The I/O channel may also be used as a discrete output. The digital outputs are transistor switched DC signals, FET
output to common rated at 30VDC 500 mA.
The output circuit is connected to the "DIO" terminal. The digital output circuit includes a LED indicator which is lit
RED when the digital output is active.
DIO
GND MODEM
Voltage-free
contact input
V+
V
-
_
+DC
Load
Max 30VDC
0.5A
DIO
GND MODEM

Chapter Three 245U-E Wireless Ethernet
man_245UE_V1.5.doc Page 19
Chapter Three OPERATION
3.0 Start-up
“Access Point” Start-up (245U-E-G)
When an Access Point (AP) unit starts up it checks to see if the Channel selection is set to “Auto” and if so will scan all
available channels, pick the quietest then begin transmitting periodic messages, called beacons, if it is configured with
a fixed channel it will immediately begins sending beacons, on the configured channel.
Beacons include information that a Client may examine in order to identify if the Access Point is suitable for link
establishment. Clients will only attempt to establish a link with an Access Point whose beacon indicates a matching
SSID. Access Points do not initiate link establishment.
“Access Point” Start-up (245U-E-A)
If the modem is configured to use “DFS” then it will behave slightly different, as it needs to comply with DFS
regulations.
When an Access Point starts up it will scan all available channels from the selected groups and then select the quietest
similar to the 245U-E-G. It will then go into a scan mode for 60 seconds where it listens for any Radar signals.
If a radar signal is detected it will flag the channel as being unavailable (Channel will stay unavailable for 30 minutes)
and then pick another random channel and go through the same scanning process until a radar free channel be comes
available.
“Client” Start-up
When a Client powers up, it scans for beacons from Access Points. While a link is not established, the Client cyclically
scans all available channels for a suitable Access Point. The Client will attempt to establish a link with an Access Point
only if it has matching SSID, Encryption method, etc. and other compatible capabilities as indicated by the beacon. If
more than one suitable Access Point is discovered, the client will attempt to establish a link with the Access Point that
has the strongest radio signal.
Link Establishment
Once a Client identifies a suitable Access Point for link establishment it attempts to establish a link using a two step
process – “Authentication” and “Association”. During Authentication the Client and Access Point check if their
configurations permit them to establish a link. Once the Client has been authenticated, it will then request an
Association to establish a link.
Status of the wireless link is indicated via the TX/LINK LED. For an Access Point, the TX/LINK LED will be OFF
while no links have been established. Once one or more links have been established, the TX/LINK LED is on GREEN.
For a Client, the Link LED will reflect the connection status to an Access Point. Link status is also displayed on the
“Connectivity” page of the web interface.
After the link is established, data may be transferred in both directions. The Access Point will act as a master-unit and
will control the flow of data to the Clients linked to it. Clients can only transmit data to the AP to which they are
connected. When a Client transfers data to another Client, it first transmits the data to the AP, which then forwards the
data to the destined Client.
Presence of a “link” does not mean that the connected unit is authorized to communicate
over radio. If the encryption keys are incorrect between units in the same system, or a
dissimilar encryption scheme is configured, the LINK led will light, however data cannot be
passed over the wireless network.
A maximum of 127 Clients may be linked to an Access Point.
How a Link connection is lost
The Access Point refreshes the link status with a Client every time a message is received from that Client. If nothing is
received from a Client for a period of 120 seconds, the Access Point sends a “link-check” message. If there is no
response to the link-check a De-authenticate message is sent and the link is dropped.

245U-E Wireless Ethernet User Manual
Page 20 Dec 2009
A Client monitors beacon messages from an Access Point to determine whether the link is still present. If the Client can
no longer receive beacons from the Access Point it assumes the AP is out-of-range and the link is dropped. Whenever a
Client is not connected to an AP, it will cyclically scan all available channels for a suitable AP.
Roaming Clients
Clients can roam within a system however if the link to the Access Point fails or the radio signal level becomes too
weak it will scan for beacons and connect to an Access Point (provided the SSID and any Encryption methods, keys,
etc are compatible). If there are multiple Access Points it will select the connection with the best signal level. This
functionality permits a client to have mobility whilst maintaining a link with the most suitable AP.
LED Indication
The following table details the status of the indicating LEDs on the front panel under normal operating conditions.
LED Indicator Condition Meaning
OK GREEN Normal Operation
OK Flashing RED / GREEN Module Boot Sequence
Radio RX GREEN flash Radio receiving data (Good Signal Strength)
Radio RX RED flash Radio receiving data (Low Signal strength)
TX/LINK GREEN Radio Connection Established
TX/LINK RED Flash Radio Transmitting
RS-232 GREEN flash Data sent from RS-232 Serial Port
RS-232 RED flash Data received to RS-232 Serial Port
LAN ON Link Established on Ethernet port
LAN Flash Activity on Ethernet port.
RS-485 GREEN flash Data sent from RS-485 Serial Port
RS-485 RED flash Data received to RS-485 Serial Port
DIO GREEN Digital Input is grounded.
DIO RED Digital Output is active
DIO Off
Digital Output OFF and Input is open circuit.
The Ethernet RJ45 port incorporates two indication LEDs. The LINK LED comes on when there is a connection on the
Ethernet port, and will blink off briefly when activity is detected on the Ethernet Port. The 100MB LED indicates that
the connection is at 100 MBit/Sec. The 100MB LED will be off for 10MB/Sec connection.
Other conditions indicating a fault are described in Chapter Four - DIAGNOSTICS.