Method of defining CBP condition is common for all actions and is described below.


    1. Functions for condition:
      • Instantaneous: Parameter instantaneous value.
      • Average: Average value of parameter for defined time period.
      • Max: Maximum value of parameter in defined time period.
      • Min: Minimum value of parameter in defined time period.
      • Difference: Difference between start value and end value of defined time period.
      • Sum: Sum of parameter value for defined time period.
    1. Relational and Logical Conditions:
      • Variable: Variable from device
      • Operator: Relational operators <, <=, >, >=, ==, !=
      • Limit type: Compare with. Valid values – Constant, another variable, self (compare with 2 consecutive values of same variable), error flag (check if variable has error flag set)
      • Limit: Constant value for comparison if type is constant
      • Compare variable: Variable for comparison
      • Device status: device status to be used in condition. This is available only for  'device status alarm' action
      • Device: It is possible to compare with variables from another device in same plant.
      • Conditional alarm on other device parameter:
        • User can use parameters from multiple devices when defining a condition.
        • On variable page user can specify a variable as ‘Global’
        • Only ‘Global’ variables of other devices are available when defining conditions of a device. But for current device itself all variables are available.
        • When we select the other device its global variable list is populated in ‘compare variable’ drop down.
      • Add button: Add condition to relational condition list
      • Relational Condition List: List of all conditions defined. You can delete a condition by clicking on X icon in each row
      • Logical Condition: Join relational conditions using a logical operator – AND, OR. Only one logical operator can be used for all conditions
    1. Condition Evaluation: This section describes additional criteria for declaring condition as true
      • Evaluation method: Different ways of evaluating the condition
        • Instantaneous – condition is declared as true when it becomes true once
        • Periodicity – assign a period for condition evaluation. E.g. declare it true if a condition occurs and stays true for 10 seconds
        • No of occurrences – assign number of occurrences to condition. E.g. declare it true if a condition occurs 5 times in 1 minute
        • Periodicity for function – this is used when a function like average, max is used for condition. E.g. declare true if average of value over 10 minutes exceeds limit
      • Periodicity: Value of periodicity and unit for periodicity (seconds / minutes / hours / days)
      • No of occurrences: Value for number of occurrences. Here periodicity is also used. Number of occurrences within given periodicity