Klemsan GTOR-4, Руководство пользователя

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GPRS/SerialGateway
Response Timeout:
In GTOR’s MODBUS network, it is the response waiting time from each serial device
that is interrogated. If no response is received from the querying device during this
time, the next remote connection query is passed.
Server Mode Communication Example:
In this scenario, it is desired to take data from a device that accepts MODBUS RTU
query using a computer that is connected to the network. MODBUS software in the
computer can create MODBUS TCP queries only from port no. 502. In this case, in
oder to have a healthy data communication, the following steps should be taken:
AĞ
MODBUS TCP
MODBUS TCP
MODBUS TCP
MODBUS TCP
MODBUS RTU
MODBUS RTU
GTOR
1 2 3
4 5 6
REQUEST
Figure 3-11 Data Communication Scenario
The serial communication parameters of the serial device in slave status are as follows:
Tablo 3-1 Settings Menu Tree
Baud Rate
57600
Stop Bit 1
Parity
None
1.
The MODBUS TCP query created by the software on the computer is sent to the
network via the GPRS.
2.
The GTOR connected to the same network takes the MODBUS TCP query via GPRS
and turns it into the MODBUS RTU query.
3.
The GTOR transmits the query to the serial device via the serial port and waits until
the timeout expires (assuming 1 second is sufficient for this scenario).
SECTION 3 CONFIGURATION SOFTWARE