OPC Configuration
The OPC Configuration feature of Assetwise Amulet comes in 2 forms, a widget and an administration page. At no point do either of these features communicate directly with the OPC interface.
OPC Widget
This widget provides a read-only summary of the OPC Tag to Point ID mappings and the related settings/configuration. It is accessible in widget format so that it can be added to dashboards, allowing multiple users the ability to browse mappings quickly, whilst not being able to modify them.
The grid itself can be sorted and filtered, and there is a scroll bar at the bottom to reveal many of the fields not visible at first, but importantly, keeping the PointID and OPC Tag on screen at all times.
Exporting to CSV – Clicking the icon to the top right of the widget will present the contents of the grid in CSV format, allowing all mappings to be used in Excel if necessary.
| Value | Default | Comment |
|---|---|---|
| Widget Heading | OPC Tag Summary | Enter the name of the widget as it is to appear in the heading. |
| Decimal Places | 1 | The number of numeric digits to appear after the decimal place in any number. |
| Refresh Period | 0 | Select a refresh period from the drop-down menu, from between 15 sec to 1 hr, or no refresh at all. |
There are no properties in relation to this widget.
If the user has permission, there will be a button at the top right, above the grid called 'OPC Configuration'. Click this button to access the administration page, which is discussed further in the section to follow.
OPC Configuration – Admin Feature
The second of the 2 forms is the area where a user can create, edit, and delete mappings via 3 main controls on the page: a tree, a form, and a grid.
To create a new mapping, you must complete the form at the top of the page.
Enter an OPC Tag is in the field provided; this is a textual string value and is mandatory.
The PointID field is also required. The PointID must match a point in Amulet, and it can only be mapped to one OPC Tag. As shown in the images above, if you browse the navigation tree, you will find the option to drag and drop PointID's into the Point ID field making configuration that little bit easier.
The Collection Frequency setting is used to let the application know how often to connect to the OPC server to get new data for transfer to Amulet. The setting is measured and stored in minutes and can be any positive number. The default is 60 minutes.
The Enabled checkbox is checked by default; if this is un-checked, the mapping will be created.
The OPC Host and OPC Server details must also be populated.
When you click Create Mapping, the mapping will be saved if all validation rules are satisfied. Otherwise, you will be directed to the fields that require attention before saving. Upon successfully creating a mapping, it will be added to the grid beneath the form.
If you click Reset Values, the form will clear altered fields and restore the default values. Nothing will be committed or saved.
All existing mappings can be modified or deleted using the grid shown below.
To modify a cell, double-click within it; this puts the cell in edit mode, so you can type, choose from a drop-down, check a box, or select from a calendar. However, these cells are not editable:
- Point Name – the name of the point as configured in the Digital Twin Explorer
- Read or Write – this is always set to READ for OPC but could be configured differently in the future
- Last Value – taken from Standard Data (the last value stored against that point)
- Units – the measurement units used for this point
- Days Since Last Data Read − a useful column to show quickly whether the OPC Data Collector is experiencing issues
Exporting to CSV – clicking the button to the top right of the grid will present the contents of the grid in CSV format, allowing all mappings to be used in Excel if necessary.
The last column of the grid shown above will contain a delete icon for each row.
