Micromod MOD: Extended Modbus (XModbus) OPC Server Users Guide - Manual (Page 27)

4 Operation and Reference
4.1 Extended Modbus OPC Server
4.1.1 OPC Tag Database
The database is typically made up of the following:
Devices: These are hardware devices (MODCELL / MOD 30ML) connected to the OPC
Server.
Groups: Tags/Signals can be grouped together into groups. Groups follow a device that
means that you can make groups of tags from a device. In the Extended Modbus
OPC database, the grouping will be based on the grouping in the CL block in
the instrument database database.
Each block in the database will be one group and will have the selected attributes of that
block. For example, if you have a block named FIC-100, the group will be called FIC-100
and the signals like PVI, SP, OP etc, will be tags belonging to that group.
Blocks inside a compound will be grouped into a bigger group with name as the
compound name.
Grouping is only for the user’s convenience. If aliases are configured in the CL block for
tags, then the tags will be attached to the devices directly (at the root level).
Tags: Tags define the properties of signals such as address of the signal, group and
device it belongs to, data type and scaling. Examples of tags are PVI, SP, and
OP etc, of a PID block.
Figure 4 .1.
OPC Server Tag
database
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