5.10 Communication
5.10.1
Network by Modbus
The device comes equipped with a RS-485 interface for networking via a Modbus. Connection to
terminals
“
D+
”
,
“
D-
”
and
“
GND
”
.
A maximum of 32 network users can be connected to the data bus. One of these devices is the
Master
.
The Master always has the address 1(display of address in installation menu:- - - - -).
The address must be set in the
“
Bus
”
menu. The sensor for the supply air and the group fault
must be connected at the
“
Master
”
device!
5.10.2
RS-485 - network design and interface parameter
You must ensure correct connection; i.e. "D+" must also be connectedon the following devices to
"D+". The same applies to "D-".
In addition, a "GND" connection must be established, as dissimilar potential (over 10 V!) will lead to
the destruction of the RS-485 interface (e.g. lightning).
GN
D
D+
D-
GN
D
D+
D-
16.04.2008
v_modbus_geraete_anschluss.vsd
general example for Modbus device connection
The data line must be conducted from one device to the next. No other type of wiring is allowed!
Always use only two wires of one lead(twistedpair) for the connection.
Examples for Modbus connection
Recommended wire types
1. CAT5 / CAT7 cables
2. J-Y (St) 2x2x0.6 (telephone wire)
3. AWG22 (2x2 twistedpair)
When using telephone
ex with four cable cores, we recommendthe following allocation:
“
D+
”
= red,
“
D-
”
= black,
“
GND
”
= white
Information
•
Pay attention to suf
cient distance from powerlines and motor wires (min. 20 cm)
•
Do not use wire shield
•
Except the data link " D+" , " D-" and " GND" - connection may no further cable cores of
the data line be used.
•
Max. allowed wire length 1000 m (CAT5/7 500 m)
Default interface parameter
Baudrate
= 19200
Bits
= 8
Patity
= Even (None, exception of devices agriculture)
Stop bits
= 1
Handshake
= none
Operating Instructions
UNIcon / Acontrol
Electrical installation
L-BAL-E051-GB 1035 Index 003
Part.-No. 00163311-GB
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