Atop MB52 Series, User Manual

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MB52XX Modbus Gateway
User Manual
Configuration
and
Setup
4.6.5 TCP Settings
A device using Modbus
/
TCP connection, which communicates over the internet, can be set in this section
.
If a
Modbus / TCP connection is needed, navigate to
Basic Settings

TCP Settings
, then choose whether or not to
enable TCP by checking on the “
Enable
” check box . Figure 4.14 shows the Modbus TCP Settings page in which a
device connected to this Modbus Gateway device is chosen to be run in
TCP Slave Operation Mode
. The device
will take the Modbus Slave role and communicate using Modbus / TCP protocol .
Figure 4.14 Modbus TCP Settings Web Page with TCP Slave Mode

Operation Mode
:
There are two radio buttons in this setting
:
TCP Slave and TCP Master
.
When running on
TCP Slave mode ( the TCP Slave radio button is checked ) as shown in Figure 4.14, the device will wait to
receive Modbus requests from a Modbus Master . The data transmission is done under a Modbus / TCP
protocol format . This means that the device will operate as a TCP Server that opens its TCP port to accept
connections . The TCP Master option will be described at the end of this section .

Remote IP Address
:
This setting shows the IP address of the device which is a Modbus slave node
.
This
address refers to the IP address that belongs to the device that is going to be controlled from the MB52XX
Series Modbus Gateway device . This device can also be considered as a TCP server of whom it is needed to
know its IP address . This option will disappear when the operation mode as TCP Master is selected, because
in that mode the device will be running as a TCP Client which does not require to publish its IP address .

TCP Port
: This setting shows the TCP port number of the device ( or Modbus Slave node in Figure 4.14 ) which
can be a number in between 1 and 65535
.
The default port number is 502
.

TCP inactivity Time Out
: A time out period, which is the maximum period of time allowed between actions,
can be set as well
.
This setting has a maximum duration of 600 minutes
(
36000 seconds
)
or 10 hours
.
If no
activity has occurred within this period, the Modbus
/
TCP connection will be automatically terminated by the
Modbus Gateway
.