provides a
logical link to an Allen Bradley PLC Device.
The tag supports: ControlLogix, CompactLogix, Micro820, Micro850, Micro870, MicroLogix, SLC and PLC-5.
The Allen Bradley PLC Tag provides a
logical link to an Allen Bradley PLC Device.
The tag supports: ControlLogix, CompactLogix, Micro820, Micro850, Micro870, MicroLogix, SLC and PLC-5.
The Allen Bradley PLC Tag supports the configuration properties of the PLC Device Tag with RTC, plus these properties:
| Property | Type | Version | Description |
|---|---|---|---|
| Channel | Reference | 2.2 | A reference to one of the following: |
| DestinationNode | USINT | 2.2 | The DF1 destination node of the PLC. The valid range is 0-254. This property is only used when the Channel property refers to an Allen Bradley Serial Communication Channel. |
| PLCType | USINT | 3.41 |
The type of this PLC. Choose one of the following:
|
| RoutePath | WSTRING | 3.41 | For tag based PLC Devices (CompactLogix, ControlLogix, Micro820, Micro850, Micro870) the communication path to get to the CPU. For more information see RoutePath Configuration Property below. |
The RoutePath configuration property is used with tag based (ControlLogix, CompactLogix, Micro820, Micro850, Micro870) PLC Devices. The configuration property tells the communication end point how to route messages to the CPU.
The RoutePath property consists of a sequence of numbers separated by commas. For example:
1,0
This tells the communication end point to forward the message to slot 0 on the backplane.
Recommended values for RoutePath:
| Communication | RoutePath | Notes |
|---|---|---|
| Serial Port on CPU | Leave the property blank. | |
| Ethernet Module | 1,n | The value n is the slot number of the CPU. |
More complex route paths are possible. For example, multiple hops across different networks.
The Allen Bradley PLC Tag supports the tag commands of the PLC Device Tag with RTC plus these commands:
| Tag Command | Version | Description |
|---|---|---|
| DirectWriteWord | 2.3 | Directly writes one or more words to an address in the PLC. |
| DirectWriteBit | 2.3 | Directly writes a single bit to an address in the PLC. |
| Refresh | 3.15 | Requests an immediate refresh of the I/O Data Point Tags associated with the PLC. |
The Allen Bradley PLC Tag builds on the features of these tag types:
To learn about Allen Bradley serial communication channels.
Allen Bradley Ethernet Communication ChannelTo learn about Allen Bradley Ethernet communication channels.
Allen Bradley Register BlocksTo learn about reading blocks of data from an Allen Bradley PLC.
To learn about abnormal conditions in SCADA applications.
For the meaning of terms used in Fernhill SCADA.