Publish Tags in Modbus TCP

The eWON allows you to publish acquired or internal Tags. Using this feature, an external software could then read the Tags value out of the eWON. For example, a supervision software running on a PC which is connected to the eWON using the Ethernet Link (local network or over a remote connection) could then read the values which eWON polls on the PLC even if the supervision software does not support directly the PLC protocol.

eWON can publish Tags using the following protocols:
– Modbus TCP
– SNMP
– Instant value files (This are csv formated files containing the actual value of each Tag)

To publish a Tag, go to the Tag Setup page (Configuration/ Tag Setup) and click on the Tag that you want to publish.
Configure the "Tag Visibility" section to indicate eWON how it has to publish the Tag. 
To publish the Tag in Modbus TCP you will need to configure it like this:

Enable the "Modbus TCP" and indicate the Modbus register on which eWON shall publish the tag value.

Now an external software can read back the value of the Tag using Modbus TCP, by specifying the eWON IP address, the Unit ID 100 (default setting of the eWON) and the Analog Output register 7.

Note: The Unit ID on which eWON publishes on Modbus TCP is by default set to 100. The UnitID can be changed in the Modbus IOserver configuration page of the eWON (Configuration/ IO Server Config/ Modbus):

This page allows also to enable or disable the Modbus publishing. By default the Modbus publishing is enabled.