Phoenix Contact FL WLAN 24 AP 802-11 User manual

AUTOMATION
UM EN FL WLAN AP/EC
Order No.: 28 88 48 2
User manual
User manual for the following WLAN devices:
FL WLAN 24 (D)AP 802.11
FL WLAN 24 EC 802.11

Designation:
Revision:
Order No.:
This user manual is valid for:
01/2009
AUTOMATIONWORX
7190_en_02 PHOENIX CONTACT
For WLAN devices with firmware Version 3.x or later
UM DE FL WLAN AP/EC
02
28 88 48 2
Designation Order No.
FL WLAN 24 AP 802-11 28 84 07 5
FL WLAN 24 EC 802-11 28 84 13 0
FL WLAN 24 DAP 802-11 28 84 27 9
User manual

FL WLAN 24 AP 802-11
PHOENIX CONTACT 7190_en_02
Please observe the following notes
In order to ensure the safe use of the product described, you have to read and understand
this manual. The following notes provide information on how to use this manual.
User group of this manual
The use of products described in this manual is oriented exclusively to qualified electricians
or persons instructed by them, who are familiar with applicable standards and other
regulations regarding electrical engineering and, in particular, the relevant safety concepts.
Phoenix Contact accepts no liability for erroneous handling or damage to products from
Phoenix Contact or third-party products resulting from disregard of information contained in
this manual.
Explanation of symbols used and signal words
The following types of messages provide information about possible property damage and
general information concerning proper operation and ease-of-use.
This is the safety alert symbol. It is used to alert you to potential personal injury
hazards. Obey all safety messages that follow this symbol to avoid possible
injury or death.
DANGER
This indicates a hazardous situation which, if not avoided, will result in death or serious
injury.
WARNING
This indicates a hazardous situation which, if not avoided, could result in death or serious
injury.
CAUTION
This indicates a hazardous situation which, if not avoided, could result in minor or
moderate injury.
NOTE
This symbol and the accompanying text alerts the reader to a situation which may cause
damage or malfunction to the device, either hardware or software, or surrounding
property.
This symbol and the accompanying text provides additional information to the reader. It is
also used as a reference to other sources of information (manuals, data sheets, literature)
on the subject matter, product, etc.

Please observe the following notes
7190_en_02 PHOENIX CONTACT
General terms and conditions of use for technical documentation
Phoenix Contact reserves the right to alter, correct, and/or improve the technical
documentation and the products described in the technical documentation at its own
discretion and without giving prior notice, insofar as this is reasonable for the user. The
same applies to any technical changes that serve the purpose of technical progress.
The receipt of technical documentation (in particular data sheets, installation instructions,
manuals, etc.) does not constitute any further duty on the part of Phoenix Contact to furnish
information on alterations to products and/or technical documentation. Any other
agreement shall only apply if expressly confirmed in writing by Phoenix Contact. Please
note that the supplied documentation is product-specific documentation only and that you
are responsible for checking the suitability and intended use of the products in your specific
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Although Phoenix Contact makes every effort to ensure that the information content is
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the information cannot be ruled out. Phoenix Contact does not offer any guarantees as to
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Phoenix Contact accepts no liability or responsibility for errors or omissions in the content
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far as liability must be assumed, e.g., according to product liability law, in cases of
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negligence, or that liability is assumed on account of loss of life, physical injury or damage
to health. This ruling does not imply a change in the burden of proof to the detriment of the
user.

FL WLAN 24 AP 802-11
PHOENIX CONTACT 7190_en_02
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well as electronic and photographic archiving or alteration requires the express written
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Internet Up-to-date information on Phoenix Contact products and our Terms and Conditions can be
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www.phoenixcontact.com.
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Table of contents
7190_en_02 PHOENIX CONTACT i
Table of contents
1 Functions and wireless technology .........................................................................................1-1
1.1 Wireless technology applications .......................................................................1-1
1.2 Wireless technology ...........................................................................................1-2
1.2.1 Wave dispersion .................................................................................1-2
1.2.2 Attenuation of radio waves ..................................................................1-3
1.2.3 Free space attenuation .......................................................................1-4
1.2.4 Antenna gain .......................................................................................1-5
1.3 Standard IEEE 802.11b/g and IEEE 802.11a/h ..................................................1-7
1.3.1 Channels in IEEE 802.11b/g ...............................................................1-9
1.3.2 Infrastructure mode - Basic Service Set ............................................1-11
1.3.3 Roaming ...........................................................................................1-12
1.3.4 Modulation method ...........................................................................1-13
1.4 WLAN applications...........................................................................................1-14
2 Wireless LAN access points/Ethernet clients ..........................................................................2-1
2.1 Device properties ...............................................................................................2-1
2.2 Properties ........................................................................................................... 2-2
2.2.1 Scope of supply ..................................................................................2-3
2.2.2 Features and fields of application .......................................................2-4
2.2.3 Front view/elements ............................................................................2-4
2.2.4 Housing dimensions ...........................................................................2-6
2.2.5 Status and diagnostic indicators .........................................................2-7
2.2.6 Mounting/removal ...............................................................................2-7
2.2.7 Mounting the antennas .......................................................................2-9
2.2.8 Module installation ............................................................................2-10
2.2.9 SIM card reader according to ISO 7816 ............................................2-12
3 Startup and functions ..............................................................................................................3-1
3.1 Notes on using the device in the 5 GHz frequency band ....................................3-1
3.1.1 Using standard 802.11a/h ...................................................................3-1
3.2 Basic settings .....................................................................................................3-3
3.2.1 Default upon delivery/default settings .................................................3-3
3.2.2 Reset to default settings ......................................................................3-3
3.3 Making contact for initial configuration................................................................3-4
3.3.1 General information about configuration .............................................3-7
3.3.2 Information pages in WBM ..................................................................3-8
3.4 Access point Setup wizard .................................................................................3-9
3.4.1 Initial configuration with the Setup wizard ...........................................3-9
3.5 "Device Information" main menu in WBM .........................................................3-16
3.5.1 "Device Information" menu ................................................................3-16
3.5.2 "General configuration" menu ...........................................................3-17

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3.5.3 "WLAN device" menu .......................................................................3-32
3.5.4 "System" menu .................................................................................3-35
3.5.5 Security in "Client" mode ...................................................................3-60
3.6 Example configuration ......................................................................................3-62
4 Technical data ........................................................................................................................4-1
4.1 Ordering data .....................................................................................................4-3
5 Technical appendix .................................................................................................................5-1
5.1 Phoenix Contact Private MIB..............................................................................5-1

Functions and wireless technology
7190_en_02 PHOENIX CONTACT 1-1
1 Functions and wireless technology
Wireless technology based on IEEE 802.11b/g is always used when a full coverage
wireless network with high data transmission rate is required.
1.1 Wireless technology applications
In industrial environments, users are often confronted with situations where devices can
only be connected via copper cables under difficult conditions or sometimes not at all.
These are often applications where data is transmitted to moving, rotating or mobile
devices.
The high requirements in terms of data transmission quality are very difficult to meet using
mechanical solutions, due to the constant mechanical strain and the associated wear on the
cables.
The use of wireless technology offers additional advantages in temporary installations, i.e.,
any applications that are frequently converted and modified. Wireless technology also
offers advantages in applications where individual devices are very remote or difficult to
access. The key advantages of wireless technology are therefore:
– The transmission medium is not subject to mechanical wear.
– Mobility and freedom of movement for the devices.
– Large radio fields allow flexible integration of devices independent of the location.
– Bridging of large distances or problematic zones, such as streets or railway lines.
– Spontaneous integration of new or temporary devices.
With simultaneous operation of several wireless technologies, interference and conflicts
between the wireless systems may occur. The following measures can be used to enable
the coexistence of different wireless technologies:
– Reduced transmission power – The transmission power is lowered to the level that is
required to maintain communication.
– Radio field planning – The careful selection of antenna characteristics, e.g., flat top
antenna or directional wireless antenna, can limit the radio field to the required area.
– Use of specified channels – Careful radio field planning can be used to select channels
used so that no areas/channels overlap during operation.
Phoenix Contact offers simulation software for use in planning wireless systems for
industrial environments. It can be used to estimate the later number of wireless
components and their positions as well as to simulate the quality of wireless coverage
(FL WST BASIC, Order No. 2692254).

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1.2 Wireless technology
Wireless technology is based on the propagation and receipt of electromagnetic waves.
These waves are not subject to wear of any kind, but respond in very different ways in terms
of propagation, dispersion, and reflection depending on their frequency. The propagation of
waves in an area is three dimensional and occurs at different strengths.
Numerous factors affect this propagation, however none of these factors can affect the
propagation to the extent that a signal is not safely detected at the receiver.
The frequency spectrum that can be used is limited by physical properties or by national
regulations. Each frequency can, depending on the transmission power, only be used once
in a specific radius around the transmitter (shared medium).
1.2.1 Wave dispersion
Every electromagnetic wave has different dispersion properties depending on its frequency.
A simple comparison can be made between wave dispersion for Wireless LAN and wave
dispersion for visible light.
Every material has a frequency-dependent attenuation, every surface material bends,
reflects, refracts, absorbs or disperses electromagnetic waves of any kind. This means that
every obstacle between the transmitter and receiver must be taken into account for data
transmission.
The emitted waves are affected by various obstacles, such as the floor, ceiling, machines,
people or vehicles, and reach the receiver via many different paths. The received waves
differ in terms of intensity, phase angle, and signal runtime. Superposition means that the
received signals are amplified or reduced. The receiver must select the best signal and the
arrival of signals on many paths must not cause problems.
Figure 1-1 Wave dispersion - many paths to the receiver
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The superposition of waves and their effect on the signal form is known as interference.
As the causes of interference are difficult to determine and often cannot be prevented,
receivers with antenna diversity have been developed to help with this problem.
In this solution, the receiver has two receiving antennas, which are positioned at intervals of
approximately one quarter of the wavelength. In this way, one of the two antennas (almost)
always receives a signal of sufficient quality. In the diagram below, a signal with a high level
reaches receiving antenna 2, whereas antenna 1 does not receive a usable signal.
Figure 1-2 Antenna diversity (diagram)
1.2.2 Attenuation of radio waves
Attenuation is a measurement of the reduction in signal output on a medium. The
attenuation is strongly dependent on the frequency and can only be acquired using
measuring instruments. The unit of attenuation is "dB" (decibel). The lower the dB value, the
lower the attenuation.
The decibel value indicates the logarithmic relationship between two values and this
enables the determination of gain/attenuation along a transmission chain through the
simple addition of individual attenuation/gain values.
The unit dB is therefore a factor and does not provide information about the absolute value.
Absolute values (levels) are specified in relation to a fixed reference variable. To indicate
the reference variable that the relevant level refers to, a letter is added to dB for
identification. Common variables are dBm <-> 1 mW, dBµ <-> µV or dBi <-> isotropic
omnidirectional antenna. The level indicator therefore indicates the factor by which a value
is greater than or less than the reference variable. Example for 20 dBm:
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Signal withahigh levelofinterference
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In the same way, each absolute value can be converted to a level. Example for 3 mW:
1.2.3 Free space attenuation
Electromagnetic waves are attenuated as they pass through media. Even air is a medium
that attenuates radio signals. The exponentially increasing attenuation through the medium
of air is known as free space attenuation. With a clear Fresnel zone (see "The Fresnel zone"
on page 1-7), free space attenuation can be calculated using the following formula:
For simple calculations in the 2.4 GHz ISM band, the expression
"32.4 + 20 x log 2400 MHz" can be replaced by the constant value 100.
1.2.3.1 Attenuation due to other effects
Radio signals are affected by obstacles and their surfaces, and in outdoor installations
variable factors such as rain, snow or humidity on surfaces also have an effect.
Figure 1-3 Effects on radio signals
Table 1-1 Free space attenuation in the 2.4/5 GHz ISM band
Distance 5 m 10 m 25 m 50 m 100 m 500 m 1000 m
Attenuation 54 dB 60 dB 68 dB 75 dB 80 dB 94 dB 100 dB At 2.4 GHz
Attenuation 61 dB 67 dB 75 dB 82 dB 87 dB 100 dB 107 dB At 5GHz
Dispersion Reflection
BendingAbsorption
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1.2.3.2 Attenuation due to obstacles
The table below lists recommended values for typical obstacles, which should be viewed as
guide values. In addition, factors such as the moisture content in walls or leaves or the type
and execution of reinforcement in concrete have a considerable effect on the actual
attenuation of radio waves.
1.2.4 Antenna gain
The antenna gain is a measurement of the gain in signal strength compared with an isotropic
omnidirectional antenna. The isotropic omnidirectional antenna is an imaginary ideal
antenna, which has the same properties in every direction. The gain of an isotropic
omnidirectional antenna is 0 dBi EIRP (Equivalent Isotropic Radiated Power).
Figure 1-4 Antenna characteristics
Table 1-2 Material-specific attenuation (recommended values)
Material 2.4 GHz frequency band
Rain/snow at 50 l/m2per hour 0.02 dB/km
Fog 0.02 dB/km
Thin walls 2 to 5 dB
Brick wall 6 to 12 dB
Concrete wall 10 to 20 dB
Concrete ceiling 20 to 40 dB
Hedge/bush 2 to 4 m 10 to 15 dB
Double-glazing 25 to 35 dB
Forest 30 to 50 m 30 to 50 dB
NOTE: Antennas in outdoor installations must be within the range of a lightning arrester.
All cables leading into buildings from outdoors (antenna cables) must pass through
lightning protection equipotential bonding systems. The requirements for lightning
protection systems according to VDE 0182 or IEC 62305 must be observed.
Phoenix Contact offers an extensive range of products for surge protection
(www.myblitz.de).
-10 -6 -3 0 0
30
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120
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-150
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1.2.4.1 Example calculation for a transceiver system
All attenuations and all gains along a transceiver path must be taken into account when
calculating the radio path. The transmission properties for the relevant frequency range
must be known for all components.
For example, for a path in the 2.4 GHz ISM band, all values are added together (gains with
positive sign, attenuations with negative sign):
The receiver reserve should be greater than 10 dB. If the connection deteriorates, WLAN
switches to a more rugged transmission mode. This also changes the receiver sensitivity.
The values that can be achieved are listed in the technical data under "Receiver sensitivity".
1.2.4.2 Notes on receiver reserve and transmission quality
The following table lists guide values for transmission quality (at maximum transmission
speed) depending on the receiver reserve. The values are taken from experience and do
not take fall-back data rates into account; the real radio path may demonstrate different
behavior.
Transmission power P = 15 dBm +15.0 dBm
Transmitter cable 3 m cable
1 adapter
-2.9
-0.3
dB
dB
Transmitting antenna Panel antenna +8.0 dBi
Free space attenuation Optimum line of sight 500 m -94 dB
Receiving antenna Panel antenna +8.0 dBi
Receive cable 3 m cable
1 adapter
-2.9
-0.3
dB
dB
Receiver sensitivity -87 dBm (must be viewed as positive) +87 dBm
Final total Receiver reserve +17.6 dB
Table 1-3 Receiver reserve and transmission quality
Receiver reserve Transmission quality
> 30 dB Very high transmission quality
25 dB to 30 dB High quality
20 dB to 25 dB Satisfactory quality
15 dB to 20 dB Sufficient quality, some packets will probably be lost
10 dB to 15 dB Poor quality with clear loss of packets, communication may
be aborted at any time
< 10 dB No communication, however may disturb other systems

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1.2.4.3 Fresnel zone
For an optimum radio link, a zeppelin-shaped free zone, known as the Fresnel zone, is also
required. The usual formula can only be used to calculate the free space attenuation
(see "Free space attenuation" on page 1-4) if the Fresnel zone is completely clear.
Usually the Fresnel zone is only taken into account for outdoor applications, but it also
applies for indoor installations. However, it is rarely used indoors because the distances are
short and other factors largely determine the range.
Figure 1-5 The Fresnel zone
1.3 Standard IEEE 802.11b/g and IEEE 802.11a/h
Standard IEEE 802.11b was the first standard to introduce a competitive and reasonably-
priced technology to the market, which could be used to implement wireless networks.
Devices that meet this standard are now considered mature and immune to interference,
and are therefore ideal for professional use in industrial applications.
Basic specifications for IEEE 802.11b/g:
– Frequency band: ISM band in range from 2400 MHz to 2485 MHz
– Use of wireless range is free of charge and does not require a license
– Gross data transmission rate for 802.11b: 1 Mbps, 2 Mbps, 5.5 Mbps, and 11 Mbps
– Gross data transmission rate for 802.11g: 6 Mbps, 9 Mbps, 12 Mbps, 18 Mbps,
36 Mbps, 48 Mbps, and 54 Mbps
– Net data transmission rate: 1 ~ 25 Mbps
– Band spread method: DSSS (Direct Sequence Spread Spectrum)
Table 1-4 Diameter of Fresnel zone depending on the distance
Distance in m Fresnel zone in m Distance in m Fresnel zone in m
2.4 GHz 5 GHz 2.4 GHz 5 GHz
5 0.8 0.5 100 3.5 2.3
10 1.1 0.7 200 5 3.3
20 1.6 1.0 300 6.1 4.0
30 1.9 1.3 500 7.9 5.2
50 2.5 1.6 1000 11.2 7.4
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– Transmission power: 100 mW (20 dBm)
– Frequency spectrum: 83.5 MHz
– Maximum number of non-overlapping channels: 3
Basic specifications for IEEE 802.11a/h:
– Frequency band: ISM band in range from 5150 MHz to 5350 MHz and 5470 MHz to
5725 MHz
– Use of wireless range is free of charge and does not require a license
– Gross data transmission rate for 802.11a/h: 5 Mbps to 54 Mbps
– Net data transmission rate for 802.11a: Up to 32 Mbps
– Net data transmission rate for 802.11h: Up to 28 Mbps
– Band spread method: OFDM (Orthogonal Frequency Division Multiplexing)
– Frequency spectrum: 300 MHz
– Maximum number of non-overlapping channels: 10 for 802.11a and 8 for 802.11h
– Transmission power 30 mW to 200 mW (depending on frequency band and country,
transmit power control required)
Please also refer to the notes on using the 5 GHz band provided in 3.1 "Notes on using
the device in the 5 GHz frequency band".

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Frequency spectrum for IEEE 802.11 a/h
1.3.1 Channels in IEEE 802.11b/g
The wireless channels in standard IEEE 802.11b/g are in the 2.4 GHz ISM band. The
frequency range includes up to 14 approved channels, each with a bandwidth of 22 MHz.
The channels overlap, which means that adjacent channels cannot be used in a wireless
network without interference. The following diagram illustrates which channels do not
overlap. Please note the following approvals:
– Channels 1 - 13 are approved in Europe.
– Channels 1 - 11 are approved in USA/Canada.

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– Channel 14 is approved in Japan
Figure 1-6 Frequencies and channels in IEEE 802.11b
1.3.1.1 Compatibility within the standard
In order to ensure the compatibility of devices from various manufacturers, about
40 manufacturers and a neutral independent test lab have joined together to form the WECA
(Wireless Ethernet Compatibility Alliance).
The WECA now uses the name Wi-Fi (Wireless Fidelity) to certify compatibility between
devices that use the 802.11 standard, and monitors the observance of the general standards.
1.3.1.2 Channel access
Similar to the CSMA/CD method in wired networks, in IEEE 802 the CSMA/CA (Carrier
Sense Multiple Access with Collision Avoidance) method is specified for channel access in
wireless networks. The system also checks that the medium is free before transmission is
started.
However, instead of a collision detection method (CSMA/CD), a collision avoidance method
(CSMA/CA) is used. To avoid collisions, a protocol is used, which reserves a channel for a
short period prior to a transmission and thus enables error-free transmission. This method
does not provide protection from the hidden node problem.
1
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13*
14**
2412
2417
2422
2427
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Frequency in Mhz
*Also permitted in Europe
** Onlychannelpermitted in Japan
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1.3.1.3 Hidden node
A collision occurs when two stations transmit simultaneously on the same medium because
each station has detected that the medium is free. This type of collision occurs when two
stations, which cannot contact one another, simultaneously transmit to a third station, which
they can both contact.
Figure 1-7 Hidden node
The MAC level RTS/CTS protocol (Request to Send/Clear to Send) specified in IEEE
802.11 provides a solution in the form of a special handshake method. RTS or CTS
telegrams (with confirmation message) are exchanged to reserve a radio channel for a
specific period of time. To prevent collisions between RTS/CTS telegrams, which would
render them useless, these telegrams are very short. The telegram length at which the
RTS/CTS mechanism is used can be specified in the device. This function is useful when
using very long telegrams, e.g., when downloading.
1.3.2 Infrastructure mode - Basic Service Set
Infrastructure mode is the simplest form of a wireless network. Communication between all
devices is via a shared access point. This constellation is called the Basic Service Set (BSS).
If the wireless range of an individual access point is insufficient (e.g., because too many
devices are present, the transmit range or the available bandwidth is insufficient), several
physically overlapping BSSs can be grouped to form a shared wireless network. This
expansion is called an Extended Service Set (ESS). In an ESS, the access points must be
connected together. This connection can be via wires, but is usually via Ethernet or via radio
paths. The use of an ESS enables devices to communicate with one another, even if they
are not in the range of a shared access point.
In addition, with ESS mobile devices can be automatically forwarded from one access point
to another without interrupting communication (roaming).
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Infrastructure mode and especially the use of ESS enables the operation of large networks
according to IEEE 802.11 and is also known as Wireless Ethernet.
Figure 1-8 Extended Service Set – Wireless Ethernet
1.3.3 Roaming
Roaming was defined in IEEE 802.11r to enable the transfer of a communication connection
from one access point to another. The following sequence was specified for roaming:
– If a device determines that the signal from an access point is too weak, it searches for
an access point with a stronger signal (scanning). A distinction is made between active
scanning and passive scanning:
Passive scanning: Tapping the medium to determine whether another access point is
available.
Active scanning: Transmitting a request to all channels. If a response is transmitted
from an access point, it contains all the information required to transfer the
communication.
– The device uses the signal strength to select the most suitable access point and sends
it an association request, which requests that it takes over the communication.
– If the response to the association request is positive, roaming was successful. If not, the
sequence starts again.
Please note that in applications such as that shown in Figure 1-8 all access points must
have the same SSID.
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ACT 100 FD
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US2US1 GND GND R1 R2
00A0451BDD
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