User guide

eWON 500-2001-4001-4002 User Guide - IO Servers Configuration
eWON 500®2001®4001®4002® Version 4_3_0 - User Guide - 10/5/05 - ©ACT'L sa - Page 79
Three topics can be used for the IO Server. These topics are used to give a common property to a group of MODBUS Tag like:
• Enable/Disable
• Poll rate
• Slave address (Modbus RTU)
• Unit address and TCP/IP address (Modbus TCP)
Warning:
Any slave address that is defined in the Topic configuration overwrites the slave address configured per Tag.
If a Tag is defined with Tag Address: 40010,5 and the global address of the topic is 5 and 10.0.0.81, the Tag is entered as Modbus
RTU but it is polled as Modbus TCP. So if you need to address slaves Tag by Tag, leave the topic address configuration empty.
6.3.2.4 Advanced parameters
Figure 48: Modbus advanced parameters configuration
Extended parameters have been added to accommodate various special operating conditions. They are entered in the edit box at the bottom of
the configuration page, conforming to the syntax below. Each parameter has a default value, so the advanced parameter edit box must only be
filled with the parameters for which default values must be changed. (c.f. “Standard IO server configuration page” page 76).
Modbus Server Properties Description
Topic enabled Enables or disables polling of all the Tags in the topic.
Slave address
This slave address is a global parameter for all the Tags of the topic. If the slave is connected
with Modbus RTU, Slave address must be entered and IP address must be blank. If the slave
is Modbus TCP, its unit address and its IP address must be entered.
Poll rate
This defines rate to which the Tag will be refreshed. In a complex application, we can imagine
that some Tags must be refreshed every second – typically for digital input - and other every
minute – typically: temperature-.
Table 50: Modbus topic configuration