Configuring the Model Alarming block

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To configure the Model Alarming block with a model

The field selectors should be configured to select the monitored variable (if it is not the model output) and model input fields.
The monitored variable source should be connected to the first input port.
The model inputs should be connected to the second input port.
The model output should be connected to the third input port.
It is possible to obtain set-points and limits from external sources, the fourth input port takes these fields. The external source could be the blueprint data source or it could be a script block that generates set-points and limits from a set of rules. Connect the Alarm Limits source to the second last input port.
It is also possible to obtain alarm codes from an external source. The blueprint data source or a set of rules configured in a script block may generate these external messages. The external message can include information such as the alarm code, an alarm message and the severity of the alarm. The fifth input port takes these fields, the alarm message output is configured on the Messages tab in the Model alarming block. If no external messages are available, the block is able to generate internal messages.
To open the block property page (the page on which the block configuration is specified), either double click on the block or right-click on the block and select Block Properties.
The model to be used by the alarming block may be specified in the Model Settings>Model block drop down box. The blueprint will automatically make the connections to the source of the model inputs and the source of the model output. This list will only include models with a single output.
If there is more than one field in the monitored variable input port, select the monitored variable from the Model Settings>Monitored Variable drop-down box.
In the Alarm Settings pane, the use of a Setpoint, Upper Bound or Lower bound on the monitored variable may be enabled or disabled using the Enable check box. To enable a setpoint, upper or lower bound simply check the box below the parameter in question.
Once a particular alarm setting (i.e. Setpoint, Upper Bound or Lower Bound) is enabled the setpoint, upper bound or lower bound may be configured. The setpoint, upper bound or lower bound may be variable or fixed fields. Fixed fields may be configured in the Model alarming block by entering the setpoint and limit values in the appropriate box (only configurable if there is no connection to the alarm limits port). Variable fields are obtained from some external source and are selected out of a drop-down list in the appropriate box (only configurable if the Alarm Limits port is connected to some source).
Fixed setpoints or limits must be typed into the appropriate box in the Alarm Settings pane. The time span that the monitored variable may spend outside the defined boundaries before the block generates an alarm may be specified in the Alarm Settings>Duration (sec) box.

Note : To be able to define fixed setpoints or limits within the Model alarming block, there may be nothing connected to the Alarm Limits port of the Model alarming block
Variable setpoints or limits are obtained from the Alarm Limits port (4^th input port from the top), they may be selected from the fields listed in the appropriate drop-down box.
The view configuration determines what the view options will be while the blueprint is running, there are 3 options available and the appropriate option may be toggled on using the radio buttons in the View Configuration pane.

Trend view + 1, as the name suggests, supplies the Trendviewer and one analysis window (either Causal or Leverages analysis). The analysis window may be selected in the drop-down window next to the Trend view + 1 radio button. If the Leverages analysis information is selected, the Only view adjustable input variables check box may be toggled on or off as desired. If toggled on, the block will only display those model inputs that are adjustable (i.e. manipulated variables) in the Leverages window. The adjustable model inputs are selected on the Model Inputs tab of the Model alarming block, as discussed below.
Trend view + 2 supplies the Trendviewer and both analysis windows. For the Leverages window the Only view adjustable input variables check box may be toggled on or off as desired.

Note : Trend view + 1 and Trend view + 2are only available if analysis is enabled on a model block and the Model alarming block is configured to use that same block for analysis purposes.

Trend + messages supplies the Trendviewer and a messages window. The messages window displays the exact time each alarm was generated and the type of alarm that was generated.

The smoothing window size should be specified in the Smoothing Window Size box, note that the duration should be specified in minutes. For both online and simulation purposes, there should be at least 10 samples per smoothing window. Thus if your data is available at 1 minute intervals, the smoothing window size should be around 10 minutes long.
The number of causes and leverages that should report to the Top Causes and Top Leverages ports respectively is specified using the N most significant indicators spin control. Thus the top 3 causes and leverages will be placed in the Top Causes and Top Leverages ports respectively if the value specified in the N most significant indicators box is 3.
If the Calculate only while alarm is active box is checked, the analysis results will only be presented when an alarm is activated

Model Inputs

On the Model Inputs tab, specify the model input variables that are adjustable. There is clearly no value in reporting that a particular variable has the highest leverage when it is not a manipulable variable. The box should be checked if the variable is manipulable.

Messages

The output from the alarms port is specified on the Messages tab.
If alarm messages are obtained externally (say from an online source or a script block) then the Code, Message and Severity fields in the External Messages pane must be configured, simply select the field that should be used to generate the output fields using the drop-down box provided. The output field names are; MessageCode for Code, MessageSeverity for Severity and Message for Message.
The alarms may also be configured within the alarming and analysis block in the Internal Messages pane.
If the monitored variable exceeds the upper limit, the message typed in the Upper Limit Exceeded box may be found in the Message output field. A severity may be assigned to such an event using the Upper Limit Exceeded Severity drop-down box and will be found in the MessageSeverity output field. There are 3 possibilities; the severity may be 0-Info, 1-Warning or 2-Critical. Define the messages that should be generated if the monitored variables falls below the lower limit in a similar way.
If the monitored variable is of bad quality, the message typed in the Monitored Variable Quality Bad box may be found in the Message output field. A severity may be assigned to such an event using the Quality Bad Severity drop-down box and will be found in the MessageSeverity output field. Once again, there are 3 possibilities; the severity may be 0-Info, 1-Warning or 2-Critical.
If the monitored variable remains within bounds the message typed in the Default Message box may be found in the Message output.
Click on Apply to save the changes

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To configure the Model alarming block without a model

It is possible for the Model alarming block to simply monitor a particular field and generate alarms if its value passes outside of the user-defined limits for longer than a user-defined time period. In this scenario, the block will not generate analysis data (i.e. causes, leverages and interrelationship graphs)

The monitored variable source should be connected to the top input port.
It is possible to obtain set-points and limits from external sources, the second last input port takes these fields. The external source could be the blueprint data source or it could be a script block that generates set-points and limits from a set of rules. Connect the Alarm Limits source to the second last input port.
It is also possible to obtain alarm codes from an external source. The blueprint data source or a set of rules configured in a script block may generate these external messages. The external message can include information such as the alarm code, an alarm message and the severity of the alarm. The bottom input port takes these fields, the alarm message output is configured on the Messages tab in the Model alarming block. If no external messages are available, the block is able to generate internal messages.
As stated above, no analysis is possible if the Model alarming block is configured to simply generate alarms.
To open the block property page (the page on which the block configuration is specified), either double click on the block or right-click on the block and select Block Properties.

Note : For this application, no model block is selected, the view configuration can only be Trend and messages and no indicator settings can be specified.
If there is more than one field in the monitored variable input port, select the monitored variable from the Model Settings>Monitored Variable drop-down box.
In the Alarm Settings pane, the use of a Setpoint, Upper Bound or Lower Bound on the monitored variable may be enabled or disabled using the Enable check box. To enable a setpoint, upper or lower bound simply check the box below the parameter in question.
Once a particular alarm setting (i.e. Setpoint, Upper Bound or Lower Bound) is enabled the setpoint, upper bound or lower bound may be configured. The setpoint, upper bound or lower bound may be variable or fixed fields. Fixed fields may be configured in the Model alarming block by entering the setpoint and limit values in the appropriate box (only configurable if there is no connection to the alarm limits port). Variable fields are obtained from some external source and are selected out of a drop-down list in the appropriate box (only configurable if the Alarm Limits port is connected to some source).
Fixed setpoints or limits must be typed into the appropriate box in the Alarm Settings pane. The time span that the monitored variable may spend outside the defined boundaries before the block generates an alarm may be specified in the Alarm Settings>Duration (sec) box.

Note : To be able to define fixed setpoints or limits within the Model alarming block, there may be nothing connected to the Alarm Limits port of the Model alarming block.
Variable setpoints or limits are obtained from the Alarm Limits port, they may be selected from the fields listed in the appropriate drop-down box.
The output from the alarms port is specified on the Messages tab.
If alarm messages are obtained externally (say from an online source or a script block) then the Code, Message and Severity fields in the External Messages pane must be configured, simply select the field that should be used to generate the output fields using the drop-down box provided. The output field names are; MessageCode for Code, MessageSeverity for Severity and Message for Message.
Variable setpoints or limits are obtained from the AlarmLimits port (1st parameter port at the top). They may be selected from the fields listed in the appropriate drop-down box .
If the monitored variable exceeds the upper limit, the message typed in the Upper Limit Exceeded box may be found in the Message output field. A severity may be assigned to such an event using the Upper Limit Exceeded Severity drop-down box and will be found in the MessageSeverity output field. There are 3 possibilities; the severity may be 0-Info, 1-Warning or 2-Critical. Define the messages that should be generated if the monitored variables falls below the lower limit in a similar way.
If the monitored variable is of bad quality, the message typed in the Monitored Variable Quality Bad box may be found in the Message output field. A severity may be assigned to such an event using the Quality Bad Severity drop-down box and will be found in the MessageSeverity output field. Once again, there are 3 possibilities; the severity may be 0-Info, 1-Warning or 2-Critical.
If the monitored variable remains within bounds the message typed in the Default Message box may be found in the Message output.
Click on Apply to save the changes

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