SEW-Eurodrive Movipro MPCI-DCMA-82-MMCX, Дополнение к инструкции по эксплуатации

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2
Properties
Functional description
Addendum to the Operating Instructions – REC5 Radio Modem
5
2 Properties
2.1 Functional description
The MOVIPRO
®
device has a "Radio Ethernet Client 5 GHz" (REC5) radio modem for
connection to a wireless infrastructure network. It can be used for the frequency
blocks 2.4 GHz (IEEE 802.11b/g) and 5 GHz (IEEE 802.11a).
The radio connection is designed for communication with the higher-level controller.
The MOVIPRO
®
device is accessible as a terminal in the network.
The radio modem has a wireless Ethernet bridge. For communication on the MAC
level, you can only connect one Ethernet station. You have to enter the MAC address
of this station in the bridge configuration. MOVIPRO
®
devices that are equipped with
SEWOS operating systems do this automatically.
Before the first logon to an access point and during the handover process, the radio
modem is searching for a suitable access point according to the user configuration.
This is called the "probing phase".
The handover probing phase starts when the signal level of the radio modem falls be-
low a certain value (cell search threshold). When the signal level of the found access
point is higher than the signal level of the current access point by a certain value (delta
SNR), the radio modem logs on to the new access point (association/authentica-
tion/4‑way handshake for WPA2‑PSK). Process data communication is not possible
during the probing and logon phase. The probing phase can be shortened by limiting
the available channels according to the regulatory domain to the channels that exist in
the plant.
Depending on the application requirements, the radio modem can be equipped with 1
or 2 wireless cards.
In one-card operation, the one card performs the entire probing with subsequent logon
phase and process data communication.
In two-card operation, the secondary card performs the probing. The primary card only
handles logon and process data communication. This omits the latency periods in pro-
cess data communication that result from the probing phases.
Two antennas are connected to a wireless card. The connections are designated as
X4211 (WLAN antenna (main)) and X4261 (WLAN antenna (aux)). If the radio modem
is equipped with two wireless cards, the logon phase and process data communication
are handled via connections X4211_1 and X4261_1. Connections X4211_2 and
X4261_2 of the second card are used for the probing phase.
INFORMATION
When the device is delivered, only the primary card is active, even though both cards
are installed physically. The second card can be activated via the user configuration.
INFORMATION
Operation of the MOVIPRO
®
device with radio modem is only permitted indoors.
2.2 Coding
The following encryption methods are supported:
• Wired Equivalent Privacy (WEP)
– Key length 64 and 128 bit
23582855/EN – 12/2017