Configure Formula Parameters for Automatic and Semi-Automatic Transfer Phases

There are three types of formula parameters: input, output, and process variable. Process variable parameters represent data such as set points or rates. Input and output parameters are used when material tracking is required. A specific data class type must be assigned to each formula parameter. The available data class options are analog, discrete, string, and enumeration. Tag assignments to the elements associated with each parameter correspond to the assigned data class of the parameter. For example, only analog tags can be assigned to the elements of an analog process variable parameter.

Input parameters have seven elements. The parameter name defines a family of information. Elements define the members of the family. The seven elements for input parameters are target, actual, high deviation, low deviation, preact, lot code, and material ID.

Output parameters have three elements. The parameter name defines a family of information. Elements define the members of the family. The three elements for output parameters are target, actual, and material ID.

Process variables parameters have six elements. The parameter name defines a family of information. Elements define the members of the family. The six elements for process variable parameters are target, actual, high deviation, low deviation, high limit, and low limit.

The configuration of the parameter type, data class, and elements is extremely important. The AVEVA Batch Management System controls a phase and interact with both the control system and the operator based on the configuration of the parameters. The following information provides a detailed explanation of the results that can be expected for different parameter configurations.

Target Element

The target element is available for all parameter and data class combinations.

To configure the Target element

1. If the target value is to be listed during the run-time processing of the phase, select the Enable Display check box. If a tag is assigned to the element, the value assigned in the recipe is written to the control system by the AVEVA Batch Management System prior to the start of the phase. Typically, the phase logic uses the target value to determine when to end the phase.

2. If the operator is allowed to modify the target, select the Edit Allowed check box.

3. If the operator must modify the target, select the Edit Required check box.

4. You can assign a default value to the target element for process variable parameters of any data class.

Actual Element

The actual element is available for all parameter and data class combinations.

To configure the Actual element

5. If the Actual value is to be listed during the run-time processing of the phase, select the Enable Display check box. If a tag is assigned to the element, the AVEVA Batch Management System reads the value of the tag, in real time, from the control system during the processing of the phase.

6. If the operator is allowed to modify the actual value, select the Edit Allowed check box.

7. If the operator must modify the actual, select the Edit Required check box.

High and Low Deviation Elements

The high and low deviation elements are available for analog process variable parameters and analog input parameters. If tags are assigned, the AVEVA Batch Management System calculates and writes the deviation values to the control system prior to the start of the phase. Deviations are recalculated whenever changes are made to the target or to the deviation elements. The high and low deviation elements are expressed as real numbers representing a percentage of the target value. For example, assume that the target value is 200, the high deviation is 3%, and the low deviation is 5%. The values that are downloaded to the control system are; a high deviation value of 6 and a low deviation value of 10.

To configure High and Low Deviation elements

8. If either of the element values is to be listed during the run-time processing of the phase, select the appropriate Enable Display check box. Typically, the phase logic uses the deviations to establish alarm limits or an acceptable phase completion range for the actual value of the parameter.

9. If the operator is allowed to modify either of the deviation values, select the Edit Allowed check box.

10. If the operator must modify either of the deviation values, select the Edit Required check box.

11. You can assign a default value to the high and low deviation elements for analog process variable parameters only.

High and Low Limit Elements

The high and low limit elements are available for analog process variable parameters and are used by the Recipe Editor and the AVEVA Batch Management System to prevent the entry of out of range values. If tags are assigned, the AVEVA Batch Management System writes the limit values to the control system prior to the start of the phase.

To configure High and Low Limit elements

12. If either of the element values are to be shown during the run-time processing of the phase, select the appropriate Enable Display check box.

13. You can assign a Default Value to the high and low limit elements.

Preact Element

The preact element is available for analog input parameters.

To configure the Preact element

• If the Preact value is to be shown during the run-time processing of the phase, select the Enable Display check box.

  If a tag is assigned to the element, the preact value defined in the process model is written to the control system by the AVEVA Batch Management System before the phase starts.

Lot Code Element

The lot code element is available for analog input parameters.

To configure the Lot Code element

14. If the lot code value is to be shown during the run-time processing of the phase, select the Enable Display check box.

15. If the operator is allowed to modify the lot code, select the Edit Allowed check box.

16. If the operator must modify the lot code, select the Edit Required check box.

17. If a tag is assigned to the element, the value assigned by the operator or the control system is to be written to the AVEVA Batch Management System during phase processing.

Material ID Element

The material ID element is available for analog input and output parameters.

To configure the Material ID element

18. If the material ID value is to be shown during the run- time processing of the phase, select the Enable Display check box.

19. If the operator is allowed to modify the material ID, select the Edit Allowed check box.

20. If the operator must modify the material ID, select the Edit Required check box.

    Formula parameter configurations for the automatic and semi-automatic transfer phase examples presented earlier are shown in the following table.