GDS C1, Инструкция по эксплуатации

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7.3 WIRELESS MODBUS SLAVE MODE
Wireless MODBUS
allows one or many C1’s function as wireless modbus slaves by
connecting their RS-485 modbus slave ports to a 10-0288 radio modem. These wireless
networks require a modbus master such as a DCS, HMI or another C1 Sixteen Channel
Controller; also equipped with a 10-0288 radio modem. As in all R. C. Systems wireless
networks, one transceiver must be designated as Server and all others as Clients. No
special configuration is required by the
master or slave since this is a standard modbus
network. However, 10-0288 radios must have the same
Hop Channel
and
System ID
settings to communicate. 10-0288 radio modems may only be configured when
connected to the C1’s
master port. If it is necessary to modify Hop Channel and
System ID
settings, the 10-0288 may be temporarily connected to the C1’s master port
for configuration then moved back to the slave port for operation.
The entire C1 modbus database, including registers and supported Function Codes, is
documented in section 5.1.
7.4 WIRELESS MODBUS MASTER MODE
C1 applications as a “Wireless modbus master” are similar to the “Wireless Receiver”
mode described in section 7.2 and wiring to the 10-0288 radio modem is identical. The
radio setup menus described in section 7.1 may also be used for configuring hop channel
and system ID settings. The difference is each Channel’s
INPUT DATA FROM menu
must be configured with the correct
MODBUS
values to match the slave device instead
of
Wireless RF900.
Wired and wireless inputs may be mixed between the C1’s sixteen
channels so it is also possible to accept wired signals from analog input option PCB’s
described in section 3.1.
This is a popular application when the modbus slave is another remote C1 or our ST-
90/QUAD controller available with built in radio modem compatible with the 10-0288.
Other modbus slave devices may also be converted to wireless by addition of another 10-
0288 at the slave’s location.
7.5 ANTENNA SELECTION
7.5.1 DIPOLE AND COLLINEAR ANTENNAS
These antennas are connected to the 10-0288 radio via a length of coax cable. If the
cable is larger than 6mm diameter (1/4 inch), do not connect the cable directly to the
radio. Thick cables have large bending radii and sideways force on the connector can
cause a poor connection. Use a short flexible pigtail (such as our 1000-2308) between
the thick cable and the radio.
The polarity of these antennas is the same as the main axis, and they are normally
installed vertically. They can be mounted horizontally (horizontal polarity), however the
antenna at the other end of the wireless link would need to be mounted perfectly parallel
for optimum performance. This is very difficult to achieve over distance. If the antenna
is mounted vertically, it is only necessary to mount the other antennas vertically for
optimum “coupling” – this is easy to achieve.