1 689 989 072 2010-06-09| Robert Bosch GmbH
6 | KTS 340 | Symbols useden
2.7 WLAN (Wireless Local Area Network)
2.7.1 Important information on WLAN
WLAN stands for Wireless Local Area Network. As
with Bluetooth, WLAN provides a radio link on the free
2.4 GHz ISM band (ISM: Industrial, Scientific, Medical).
This frequency range is subject to government regula-
tions, but may be used without a license in most coun-
tries. Consequently a large number of applications and
devices employ this frequency band for transmission.
This can result in frequency interference.
Depending on ambient conditions, the WLAN link may
therefore deteriorate, e.g. in the case of Bluetooth links,
cordless telephones, radio-controlled thermometers,
radio-controlled garage door openers, radio-controlled
light switches or radio-controlled alarm systems.
i Bluetooth can lead to interference in the bandwidth
of the WLAN network. The antennas of Bluetooth
and WLAN devices should be at least 30 centimeters
apart. Do not plug Bluetooth USB adapters and WLAN
sticks into adjacent USB slots on PCs/laptops. Use
the USB extension cable (special accessory) to main-
tain a distance between the Bluetooth USB adapter
and the WLAN stick on the PC/laptop.
i Exercise extreme caution if wearing pacemakers
or other vital electronic devices when using radio
systems, as proper functioning of these items could
be impaired.
Note the following to ensure the best possible connec-
tivity:
R The WLAN radio signal always tries to find the most
direct path. When setting up the PC/laptop and ac-
cess point (see section 2.6.2), make sure there are
as few obstacles as possible (e.g. steel doors and
concrete walls), which could interfere with the radio
signal from and to the KTS 340. Inside buildings, the
range of the WLAN is also greatly influenced by the
construction materials used. Conventional masonry,
wooden walls and certain types of dry construc-
tion wall scarcely impede radio waves. Thin gypsum
walls can however cause problems, as considerable
amounts of moisture may accumulate in the gypsum
and result in the absorption of radio signals. Concrete
(and in particular reinforced concrete) largely blocks
out radio waves. Cellar ceilings are often impenetra-
ble. Generally speaking, walls with a lot of installed
metal (e.g. pipes, wires) obstruct radio waves.
R Radio reception is also impeded by large metal
objects such as radiators and window frames as
well as active sources of interference such as DECT
telephones and microwave ovens.
R Have your network infrastructure installed and
tested in advance by a data systems expert.
R Keep the SSID and the codes for the radio link in a
safe place. Make sure these data are readily to hand
in case faults occur.
R We recommend a thorough inspection of the pre-
mises on commissioning: Establish where in the
building the KTS 340 works properly and where the
operating limits are.
R If the KTS 340 is to be used in a vehicle (Faraday
cage), radio communication can be severely limited.
R The radio link is affected by weather conditions. The
reception signal may therefore vary.
R Please contact your network administrator with any
queries.
2.7.2 Information on access points
A wireless access point is an electronic device, which
acts as an interface between a radio network and a
cable-connected computer network. It provides a wire-
less connection between the KTS 340, the PC/laptop
with ESI[tronic] Startcenter and a printer, for example.
i We recommend using WLAN standard IEEE 802.11g
(data transmission rate max. 54 Mbps) for the access
point. The "extended range" function is not supported.
Please note the following:
R The access point should be located as centrally and
high up as possible, ideally under the ceiling.
R The access point antenna should face downwards
towards the floor.
R In the event of a poor connection it may be useful to
change the set channel on the access point. If pos-
sible, avoid using neighboring channels to channels
that are already in use.
R We recommend that encryption of radio communica-
tions is configured at the access point.
2.7.3 Information on WLAN for USA and Canada
USA:
Changes or modifications not expressly approved by
the party responsible for compliance could void the
user’s authority to operate the equipment.
Canada:
Operation is subject to the following two conditions:
R this device may not cause interference, and
R this device must accept any interference, including
interference that may cause undesired operation of
the device.
This Class [B] digital apparatus complies with Canadian
ICES-003.