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The diagram could now look like this. 7T recommends that you create a network diagram for the stations and PLCs directly in the IGSS configuration.
Purpose
If a PLC is being serviced, the operator will get communication alarms in the Alarm List. In that case, the operator may want to temporarily suspend the communication.
The operator can do this directly from the process diagram by changing the set point value of the online suspend node object.
Before you begin
Before you create the online suspend node object, a node status object must have been created for the relevant node.
The online suspend node functionality is not available when you are using event-based communication with the node. Some drivers support both polled and event communication. Only polled communication will work.
Drivers which only support event-based communication, such as the OPC Client-Side Driver (42) and the Siemens SICOS drivers, are not supported by this feature.
How to create the online suspend node object in Definition
Go to the diagram where the node status object is located.
Right-click the node status object and select Copy.
Right-click again and select Paste ® As Reference.
Move the new reference to the wanted position and double-click it to change its properties.
Click the Analog tab and type a description, for example, SUSPEND in the Description field.
On the Edit Mapping tab, do the following:
In the Atom list, enable the Set Point atom.
Under I/O mode, select Local.
In the Driver drop-down list, select the relevant communication driver.
In the Node drop-down list, select the relevant node.
Click the Display tab and do the following:
In the Show area, clear the Enable check box under Name and select Description instead. This is done to show the description defined under step 5 on the process diagram.
In the State / Value area, select Set Point under Atom. This is done to show the suspend state. When the set point is "1", the node is suspended. When the set point is "0", it is in normal operation.
Click OK to close the dialog box.
The diagram could now look like this. 7T recommends that you create a network diagram for the stations and PLCs directly in the IGSS configuration.
How the operator suspends node communication
When the configuration is installed and started, the operator can suspend / resume communication with the node as follows:
In the Supervise program, go to the diagram showing the online suspend node.
Click the node and select SP(Set Point) in the menu.
Enter the value "1" to suspend the node.
The value "1" is now shown beside the text "Suspend" and process values from this node are no longer collected. In this example, Node.0.1.0 is suspended. The node will remain suspended even if the configuration is stopped and restarted.
To resume communication with the node, change the set point value to "0".