Alias Group

Overview

The Alias Group object allows custom item names to be linked to protocol item names. This is particularly useful with numeric item names. 

Alias Items and Groups

To create an alias for use at the $Server level for register 5176 which is "Mass" for the Modbus Omni Protocol, the Alias Name would be entered as ‘ModbusOmniDevice.Mass’ (including the device name), and the corresponding item name would be entered as ‘ModbusOmniDevice.5176’ (also including the device name). Server level alias groups are created on the Aliasing tab of the $Server object.

An alias group can also be created for use with a single device or can be created for a group of devices of the same protocol if the tags are the same.  

Using the same example as above, an alias name at the device/protocol level would be entered as ‘Mass’, and the corresponding item name would be entered as ‘5176’. An OPC Client that wanted the Mass value from the device named ModbusOmniDevice would use an OPC item named ‘ModbusOmniDevice.Mass’.

Item Modifiers

Item modifiers and item scaling can be used in alias groups, with the modifier will be appended to the item name and NOT the alias name. For example if the raw value returned for Mass is 2500 and the scaled value should be .25, the alias name might be entered as ‘Scaled Mass’ and the item name would be entered as ‘5176{SG:.001,0}’.  For more information on item scaling, please see Item Scaling section.

Configuration

General Tab

See General Object Configuration page.

Alias Records

Edit Records

Click the Edit Records button to open the Alias Record Collection dialog box to add the alias names and item names.

Click Add to enter the appropriate number of New Record items.

Click Remove to delete any unwanted New Record items.

Click Tabular Display to view all New Record items at once.

Alias Name

The name by which the item will be referenced.  Max Length: 255 characters.

Item Name

The item name of the point in the device.  Modifiers and scaling can appended to the Item Name.  Max Length: 255 characters.

Record Id

Used to describe this entry.  Max Length: 50 characters.

Options

Output Destinations

Each item in an alias group are sent collectively to different destination, however an alias group does not have to be sent to all destinations.  

     MQTT: Sends the items to current subscribed MQTT listeners

     ACM Mobile: Sends the items to ACM Mobile app user

     Persistent Storage: Send the items to ACM database to be available for failover.

Interval

This is schedule interval that is applied to the items in the alias group.