Functions
WE Configuration
Modbus ON Co9 -> Fb00 = ON
Modem OFF Co9 -> Fb01 = OFF
Modbus 16-bit addressing OFF Co9 -> Fb04
Parameters*
WE Parameter level / Range of values
Station address (ST.-NR) 255 PA9 / 1 to 247 (1 to 999 with Co9 -> Fb04 = ON)
Baud rate (BAUD) 9600 PA9 / 300 to 19200
* –> Section 9.3 (“Description of communication parameters to be adjusted“)
9.3 Description of communication parameters to be adjusted
Station address (ST.-NR)
This address is used to identify the district heating controller in bus or modem mode. In a system,
each controller needs to be assigned a unique address.
Baud rate (BAUD)
In a bus system, the baud rate refers to the transfer speed between control system and district
heating controller. In modem mode, baud rate refers to the transfer speed between district heat-
ing controller and modem.
The baud rate adjusted at the district heating controller must correspond with the baud rate of
the control system, otherwise communication cannot be established.
Cyclic initialization (I)
This parameter defines the period of time for a cyclical issue of the initialization command
“ATZ“. The command is not issued during dial-up or when connected. “ATZ“ causes the con
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figuration profile 0 to be copied to the active profile, provided the modem parameters have
been set and saved in profile 0 using a suitable terminal program.
Typical initialization of a modem with a terminal program:
AT & F (restores modem to its factory settings)
OK (response of the modem)
ATEOSO = 1 (command input, EO: echo off;
SO = 1: answer on first ring)
Modem dialing pause (P)
It is recommended to observe an interval of approx. 3 to 5 minutes between dialing up to the
control system/or sending a text message or fax to avoid a permanent overloading of the (tele
-
communications) network. The modem dialing pause is the interval between two dialing at
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tempts.
EB 5179 EN 79
Communication