Configure Interlocks
- Last UpdatedJul 13, 2023
- 3 minute read
Plant SCADA allows you to represent the interlocks that exist in a production facility within a Situational Awareness project (see Interlocks). The activity associated with an interlock can then be presented to an operator at runtime in the Information Zone.
To configure interlocks in your Plant SCADA project you need to complete the following tasks.
Create the required equipment references
Equipment References allow you to create connections in your equipment model that reflect the interlocks that exist in the field. They are defined in the Equipment view of the System Model activity (see Define Equipment References for more information).
When defining an equipment reference to represent an interlock, use the following fields:
|
Field |
Description |
|---|---|
|
Equipment |
Enter the name of the piece of equipment that will change state when an interlock is triggered. By default, the "Running" item will change state when an interlock is triggered. If this is not the correct item, use the runtime parameter "Interlock_StateItem" to specify a different state item (see Set the "Interlock_StateItem" Runtime Parameter below). |
|
Referenced Equipment |
Enter the name of the piece of equipment where the triggering action will occur. |
|
Referenced Item |
Enter the name of the equipment item in the referenced equipment that will trigger the interlock when a change of state occurs. |
|
Category |
Identify the type of interlock you are creating. Enter the whole name of the category in the format "Interlock.<category>". The Situational Awareness Starter Project provides the following categories:
|
|
Comment |
Enter a description of the interlock in the Comment field. If no comment is entered, the Information Zone will display the 'cluster.equipment.item' name. |
You can also use an Equipment Reference to configure a bypass for an interlock. See Configure a Bypass for an Interlock.
Configure interlock trigger items
By default, the "Running" item will change state when an interlock is triggered by a referenced piece of equipment. If required, you can specify a different state item. To do this, use the runtime parameter "Interlock_Stateitem".
Runtime parameters are defined in the Equipment view of the System Model activity (see Define Equipment Runtime Parameters for more information).
When defining the runtime parameter, use the following fields:
|
Property |
Description |
|---|---|
|
Cluster |
Enter the name of the cluster to which the equipment is assigned. |
|
Equipment |
Enter the name of the piece of equipment that will change state when an interlock is triggered. |
|
Name |
A name for the parameter, in this case "Interlock_StateItem". This indicates that an alternative item name (entered in the Value column) has been defined. |
|
Value |
Enter the name of the equipment item that will change state when an interlock is triggered. |
|
Is Tag |
Set this to FALSE. This field defaults to TRUE if no value is specified. If you do not enter FALSE, interlocks will not recognize your state item and not function correctly. |
Note: You can change the default state item from "Running" for all equipment at a global level using the INI parameter [Interlock]StateItem.
Create the required alarms
Alarms are used to generate the events required to that track interlock activity. They are used to determine how long an interlock has been active, or when it was last active.
To support interlocks, you need to configure the following alarms:
-
One for the item that changes state when an interlock is triggered.
-
One for each of the items that trigger an interlock in any referenced equipment.
Note: It is recommended that these alarms be hidden from the operator. To do this, assign the alarms to an alarm category that has the ShowOnActive property set to FALSE. If you want the operator's reason for a bypass to appear on the SOE page, set the ShowOnSummary to TRUE. See Add an Alarm Category.