Tag Configuration

Important: You do not have the latest version of Historian! You are missing out on the newest capabilities and enhanced security. For information on all the latest features, see the Historian product page. For more information on upgrades, contact your GE Digital sales agent or e-mail GE Digital Sales Support. For the most up-to-date documentation, go here.

Configure Tags

To display the Tag Maintenance screen, click the Tags link in any of the Historian Administrator screens. The Tag Maintenance screen lets you read and modify all tag parameters for the Historian system.

To access information on a specific tag or group of tags, however, you must first search for the tags. You can search for tags in the Historian Tag Database by clicking the Search Historian Tag Database link. You can also add tags manually or automatically from the collector by clicking the appropriate link in the second line of the display.

Note:

There is no limit to length of Historian tag names in the Data Archiver. However, different client applications may have their own limits.

If you add a tag with a tag name greater than 25 characters in length, the characters beyond 25 are not visible in the Tags list on the Historian Administrator Tag Maintenance screen. To see the entire tag name, place the mouse cursor over the tag to see a ToolTip that displays the full tag name.

Dynamic Collector Updates

The dynamic collector update feature ensures that any modifications done to the tag configuration do not affect all the tags in a collector. Only the tags that stop data collection will record zero data and bad quality without restarting the collector. In other words, the tags that do not stop data collection do not record bad data samples to the collection.

Whenever you add tags, delete tags, or modify certain tag properties, the following collectors reload only the modified tag(s) without restarting the collectors.

  • OPC Collector
  • OPCUA Collector (Linux)
  • OPCUA Data Collector
  • iFIX Collector
  • Calculation Collector
  • Simulation Collector
  • Server to Server Collector
  • PI Collector
  • PI Distributor
  • Wonderware Data Collector

By default, the On-line Tag Configuration Changes option is enabled. When this option is enabled, tags can stop and restart collection without restarting the collector. If you disable the On-line Tag Configuration Changes option, any changes you make to the tags do not affect collection until after you restart the collector. To disable or enable the On-line Tag Configuration Changes option, open the Advanced tab of the Collector Maintenance screen. To restart the collector, stop and start the collector service or executable.

Note: Restarting the collector stops and restarts the tag(s) collection and may record bad data samples to the collection.

All the collector configuration changes done within a 30 second time frame are batched up together and applied to the collector. If the modified tags get zero bad markers and available runtime values at the same time, then precedence is given to available runtime values instead of zero bad markers.

Note: To begin collecting modified data faster, update/modify a small set of tags at a time. If you are updating large sets of tags at the same time, disable the On-line Tag Configuration Changes option before you start and restart the collector after you are done to minimize the amount of bad data collected.

Viewing Tags by Name or Description

The Historian Administrator allows you to view tags by name, description, or both. After you select a view type, that view type is retained when you re-open the Historian Administrator.

  • To view the tags by name, right-click in the Tag Maintenance screen and select View by Tagname from the menu.
  • To view the tags by description, right-click in the Tag Maintenance screen and select View by Description from the menu.
  • To view the tags by both name and description, right-click in the Tag Maintenance screen and select View by Tagname and Description from the menu.

Browsing for Tags

By default, the Historian clients can return a maximum of 100K tags. If the Historian clients are configured to retrieve more than 100K tags, configure the maximum tags the search can return by adding the MaxTagsToRetrieve registry key.
  1. On the Start menu, click Run, type Regedit, and then click OK.
    The Registry editor appears.
  2. Open the following key folder: HKEY_LOCAL_MACHINE\SOFTWARE\Intellution, Inc.\iHistorian\Services\DataArchiver\
  3. Create a new DWORD called MaxTagsToRetrieve.
  4. Set the decimal value to a number greater than 100,000.
    The value that you enter represents the maximum number of tags the search can return.
    Note: The value should be more than 100K. If you entered a value less than 100K, then the search will return 100K tags by default.
  5. Click OK and then close the Registry Editor.
  6. To reflect the changes made in the registry, restart Data Archiver services.
    Note: You can also use the browse filter criteria to return just the specific tags you are looking for from the Historian Database.

Rename Tags

Note: To rename a tag, you must be a member of the administrator's group with tag level security.

Historian allows you to rename tags through the Non-Web Historian Administrator, Excel Add-in, ihuAPI, and ihSDK. New tag names are called active tag names and old tag names are called aliases.

Tag renaming will only update or modify tag names without modifying or updating the tag properties. If you want to modify the properties of a newly named tag, be aware that all of the aliases tag properties will also be updated.

Whenever you rename/alias a tag, only the active tag name (that is, the new tag name) will be visible in the Tags list on the Historian Administrator Tag Maintenance screen. You can rename tags multiple times, but only the latest active tag name will be visible in the Tags list. You can also retrieve the data using any alias (that is, the new or old tag names). However, the Tag Maintenance screen will display only an active tag name (that is, the new tag name).

Whenever you change or copy a tag name, the information about the old tag name, new tag name, and time stamps are all recorded in the audit trail. You can also view the previous tag names. To view the previous tag names, right-click on the tag name and click Show Previous Tagnames.

Note: After renaming tags connected to Historian 3.5 collectors, you must restart the respective collectors before browsing the tags.
Be aware of the following when you are using the Tag Rename feature:
  • If you modify a renamed tag property, then all of the alias' tag properties will also be updated.
  • If you delete a renamed tag, then all the aliases will also be deleted.
  • You can rename tags multiple times, but only the latest active tag name (renamed tag name) will be visible in the Tags list.
  • If you rename a tag, the tag count does not increase.
  • If you copy a tag, then the tag count increases.
  • An alias can be queried, but cannot be modified or deleted.
  • You can use any of the following Application Program Interfaces (APIs) to rename tags:
    • ihSDK
    • ihUAPI
    • ihAPI
    • Excel Add-in

Renaming a Tag

  1. Click the Copy/Rename Tag link in the Tag Maintenance screen.
    The Copy/RenameTag dialog box appears.


  2. Select the Rename (Alias) Tag option.
  3. Enter a new tag name, and click OK.
    Note: When you rename tags, if you are connecting to Historian 3.5 collectors, then you must restart the respective collectors before you can browse the tags.
  4. To view previous tag names:
    1. Right-click on the tag name, and click Show Previous Tagnames.

Rename Tags Permanently

Historian allows you to permanently rename tag names. You can permanently rename a tag if you no longer want to read and write a tag by its previous name. Permanent rename makes the previous tag name available for new usage. For example, if you had permanently renamed Tag A to Tag B, then you could create a new tag with the name Tag A with no linkage to the previous tag.

Things you need to know when you are using the Permanent Rename feature:
  • If you permanently rename a tag, the tag name will be updated with the new tag name and the old tag name will be lost.
  • You can permanently rename tags multiple times, but only the latest tag name (new tag name) will be visible in the Tags list.
  • If you permanently rename a tag, the tag count does not increase.
  • Store and forward data will be lost if you do a permanent rename and the data is sent using the old tag name.
  • There will be loss of data during the process of permanently renaming a tag. Best practice is to stop the collector, permanently rename the tag, and then restart the collector.
  • If a trigger tag to other tags is permanently renamed, you need to re-assign the new trigger name to the affected tags.
  • You can use any of the following Application Program Interfaces (APIs) to permanently rename tags:
    • ihSDK
    • ihUAPI
    • Client Access API
    • Excel Add-in

Renaming a Tag Permanently

  1. In the Tag Maintenance screen, click the Copy/Rename Tag link.
    The Copy/Rename Tag dialog box appears.

  2. Select the Permanent Rename option.
  3. Enter a new tag name, and click OK.
    A message box appears.
  4. Click Yes to permanently rename the tag.

Copying Tags

  1. Click the Copy/Rename Tag link in the Tag Maintenance screen.
    The Renaming Tag dialog box appears.

  2. Select the Copy option.
  3. Enter a new tag name.
  4. Click OK.

Add Tags Manually

Typically, you add tags to Historian by browsing the data source. Refer to Searching for Tags for more information. If you need to add a tag manually, use the following procedure.

Whenever you add tags, delete tags, or modify certain tag properties, the following collectors reload only the modified tag(s) without restarting the collectors.
  • OPC Collector
  • iFIX Collector
  • Calculation Collector
  • Simulation Collector
  • Server to Server Collector
  • PI Collector
  • PI Distributor

The dynamic collector update feature ensures that any modifications to the tag configuration do not affect all the tags in a collector. Tags that stop data collection may record zero data and bad quality without restarting the collector. Tags that do not stop data collection do not record bad data samples to the collection.

By default, the On-line Tag Configuration Changes option is enabled, which allows a tag to stop and restart data collection without restarting the collector. If you disable the On-line Tag Configuration Changes option, any changes you make to the tags do not affect collection until after you restart the collector. To enable or disable the On-line Tag Configuration Changes option, click the Advanced tab of the Collector Maintenance screen.

To restart the collector you must stop and start the collector service or executable. Restarting the collector stops and restarts the tag(s) collection and may record bad data samples to the collection. All the collector configuration changes done within a 30 second time frame are batched up together. To collect the modified data faster, update/modify a small set of tags at a time.

Note: When updating large sets of tags at the same time, best practice is to disable the On-line Tag Configuration Changes option and restart the collector after modification.

Adding a Tag Manually

  1. Click the Add Tag Manually link in the Tag Maintenance screen.
    The Add Tag Manually dialog box shown in the following figure appears.

  2. Select a collector from the drop-down list in the Collector Name field. This associates the new tag with a specific collector.
  3. Enter the Source Address and Tag Name in the appropriate fields.
  4. Select the data store in the Data Store field.
  5. Select a Data Type from the drop-down list.
  6. If the tag is an Array tag, select the Is Array Tag option.
  7. For fixed string data types only, enter a value in the field adjacent to the Data Type field.
  8. Select Seconds, Milliseconds, or Microseconds in the Time Resolution field.
  9. Click OK to add the tag.
    Note: If you manually add a Server-to-Server tag, set the Time Adjustment field for the tag to the Adjust for Source Time Difference option after you add the tag. The Time Adjustment field is located on the Advanced tab in the Tag Maintenance screen. This field applies only to Server-to-Server tags that use a polled collection type.

Adding Uncollected Tags

  1. Select the desired tag(s).
    • Select a single tag by clicking on the name of the tag.
    • Select multiple individual tags by pressing the Control key and selecting the tags.
    • Select a contiguous group by pressing the Shift key and clicking the first and last tag of the group.
    • To select all tags, click Select All.
    • To clear all selections, click Unselect All.


  2. When you have selected all tags you want to add, click Add Selected Tags.
    The selected tags are added to the Historian Tag Database.

    After you have added the tags, the Tag Maintenance screen appears and the lower left portion of the screen displays a list of all tag names added to the Historian Tag Database. To show all tags, click the Search Historian Tag Database link on the Tag Maintenance screen and search for all tags.

Delete Tags

Historian allows you to delete and permanently delete tags. When a tag is deleted, it is removed from the tag database, but all data for that tag is retained in the archive and the tag name cannot be re-used. Since the tag data is still available from the archive, you can still reference that tag from within a calculation formula, for example, or by using the Excel Add-In.

When a tag is permanently deleted, all the data for that tag is removed from the archive and the tag name is available for reuse. For more information, see Permanently Deleting Tags.

Whenever you delete tags, the following collectors reload only the modified tag(s) without restarting the collectors.
  • OPC Collector
  • iFIX Collector
  • Calculation Collector
  • Simulation Collector
  • Server to Server Collector
  • PI Collector
  • PI Distributor

By default, the On-line Tag Configuration Changes option is enabled, which allows a tag to stop and restart data collection without restarting the collector. If you disable the On-line Tag Configuration Changes option, any changes you make to the tags do not affect collection until after you restart the collector. To enable or disable the On-line Tag Configuration Changes option, click the Advanced tab of the Collector Maintenance screen. To restart a collector, stop and start the collector service or executable.

Restarting the collector stops and restarts the tag(s) collection and may record bad data samples to the collection. All the collector configuration changes done within a 30 second time frame are batched up together. To collect the modified data faster, update/modify a small set of tags at a time. If the modified tags get zero bad markers and available runtime values at the same time, then precedence is given to available runtime values instead of zero bad markers.

Tip:
  • To collect the modified data faster, update/modify a small set of tags at a time.
  • When updating large sets of tags at the same time, best practice is to disable the On-line Tag Configuration Changes option and restart the collector after modification.

Deleting A Tag

  1. In the Tag Maintenance screen, select a tag from the list in the left-hand window of the screen.
    The tag information for that tag fills in the right-hand column.
  2. Click the Delete button at the bottom right of the screen.
    The Delete Tag dialog box shown in the following figure appears.

  3. Select the Remove Tag from System option and click OK.
    This removes the tag from the Tag Data-base but retains any data for that tag in the archive.
    Note: Since the tag data is still available from the archive, you can still reference that tag, for example, from within a calculation formula, or by using the Excel Add-In.
    A message box appears asking you to confirm the deletion.
  4. Click Yes to delete the tag.

Deleting Tags Permanently

Historian allows you to delete and permanently delete tags. When a tag is deleted, it is removed from the tag database, but all data for that tag is retained in the archive and the tag name cannot be re-used. When a tag is permanently deleted, all the data for that tag is removed from the archive and the tag name is available for reuse. For more information, see Deleting Tags.
CAUTION:
When a tag is permanently deleted, you can no longer query the data for that tag, since the data was removed from the archive.
  1. In the Tag Maintenance screen, select a tag from the list in the left side of the screen.
    The tag information for that tag fills in the right-hand column.
  2. Click Delete.
    The Delete Tag dialog box appears as shown in the following figure.

  3. Select the Permanently Remove Tags From System option and click OK.
    A message box appears asking you to confirm the deletion.
  4. 4. Click Yes to permanently delete the tag.
    The tag is removed from the Tag Database. The tag data is removed from the archive. The tag name is now available for re-use.

Stopping or Resuming Tag Data Collection

  1. To stop data collection on a tag:
    1. Open the Tag Maintenance screen.
    2. From the list in the left-hand window of the screen, select a tag.
    3. In the window on the right side of the screen, select the Collection tab.
    4. For the Collection field, click the Disabled option.
    5. Click Update.
  2. To resume data collection on a tag:
    1. Open the Tag Maintenance screen.
    2. From the list on the left of the screen, select the tag.
    3. In the window on the right, select the Collection tab.
    4. For the Collection field, click the Enabled option.
    5. Click the Update button.
      Data collection for that tag resumes.

Modify Tag Parameters

By default, the On-line Tag Configuration Changes option is enabled, which allows a tag to stop and restart data collection without restarting the collector. All collector configuration changes done within a 30 second time frame are batched up together. To collect the modified data faster, update/modify a small set of tags at a time. When updating large sets of tags at the same time, best practice is to disable the On-line Tag Configuration Changes option and restart the collector after modification.

If you disable the On-line Tag Configuration Changes option, any changes you make to the tags do not affect collection until after you restart the collector. To enable or disable the On-line Tag Configuration Changes option, click the Advanced tab of the Collector Maintenance screen.

CAUTION:
Restarting the collector stops and restarts data collection and may record bad data samples to the collection.

Collectors that Reload instead of Restarting

Whenever you modify tag parameters, the following collectors reload only the modified tags without restarting the collectors.
  • OPC Collector
  • iFIX Collector
  • Calculation Collector
  • Simulation Collector
  • Server to Server Collector
  • PI Collector
  • PI Distributor

Tag Properties that Cause Tag Collection to Stop and Restart

Changes to the following tag properties cause tag collection to stop and restart, assuming the On-Line Tag Configuration Changes option is enabled.
  • Collector Name
  • Collector Type
  • SourceAddress
  • Spare 1-5
  • Data Type
  • Collection Interval
  • Collection Offset
  • Collection Disabled/Enabled (CollectionDisabled in SDK)
  • Collection Type
  • TimeStampType
  • Calculation Dependencies (in SDK) or Calculation Triggers (in the Historian Administrator) (Applies to Server-to-Server and Calculation Collectors only.)

Tag Properties that Do Not Cause Tag Collection to Stop and Restart

Changes to the following tag properties do not stop and restart tag collection. The collectors use these new values immediately if the On-Line Tag Configuration Changes option is enabled.
  • High Engineering Units
  • Low Engineering Units
  • Input Scaling
  • High Scale
  • Low Scale
  • Collector Compression
  • Collector Deadband Percent Range
  • Collector Compression Timeout

Displaying Tag Trends and Raw Data

The Historian Administrator can display trend data for a selected tag. Note that the tag trend should not be used for detailed data. Trend data is not supported for Array tags. The Historian Administrator can also display the most recent ten raw samples for a selected tag.
  1. To display a trend of data for a selected tag:
    1. Select a tag in the Tag Maintenance screen.
    2. Right-click the tag and select Trend.
      The screen shown in the following figure appears.


      The screen displays the trend of data over a selected time period.
    3. Specify the time period and other parameters by clicking on the Criteria button at the bottom of the display.
      The Trend Criteria dialog box shown in the following figure appears.


  2. To select criteria for the trend display:
    1. Enter the Start Time and End Time in the appropriate fields or browse to the times and select them.
    2. In the Sampling field, select the data type to use for the display.
    3. Enter a value for the time interval on the x-axis of the display.
    4. Select the units for the time interval from the drop-down list (seconds, minutes, hours, or days).
    5. Enter the criteria string.
      You can enter the sampling mode, calculation mode, and/or query modifiers in this field. Query modifiers are used to specify various ways of retrieving data from Historian. For example, you can request raw data with good quality only by specifying the criteria string as: RAWBYTIME#ONLYGOOD. The sampling mode specified with criteria strings takes precedence over the mode specified in the Sampling field.
    6. Click OK.
    7. Scroll back and forth on the x-axis time scale by clicking on the single and double left and right arrows at the bottom of the screen. The single arrows move the duration ahead by 50% of the span. The double arrows move the duration ahead by 100% of the span.
  3. To Display the Last Ten Raw Data Samples:
    1. Select a tag in the Tag Maintenance screen.
    2. Right-click the tag and select Last 10 Values.


Array Tags

Historian allows you to store a set of values with a single timestamp and single quality and then read the elements back individually or as an array. In Historian, a tag can be modified to an array tag by selecting the Is Array Tag property.

When using Array tags, be aware of the following:
  • The size of the array tag does not need to be configured. The Data Archiver will store the number of elements that were written.
  • The maximum number of elements that an array tag can store is 10,000. If this limit is exceeded, Historian does not accept any further elements.
  • If you are retrieving the data of an array tag using a previous version of Historian Client, then the array tag will be displayed as a Blob data type.
  • You cannot associate an Enumerated Set to an array tag.
  • Fixed String and Scaled data types are not supported.
  • You cannot make an array of a User Defined Type.
  • Scaling, Collector Compression, and Archive Compression does not apply to array tags.
  • An array element cannot be used as a Calculation Trigger.
  • Trend data is not supported for array tags.
  • TagStats calculation mode is not supported.

Changing a Tag to An Array Tag

You can modify multiple tags to an array tag. An array tag is indicated with '*' in the tags section.
Note: If a tag is changed to an array tag or vice versa, then only the latest data would be retrieved. If you want to get the old data, you need to change the tag back to its previous type.
  1. Change a tag from the Collection tab.
    1. Open the Tag Maintenance Screen and click the Collection tab.
    2. Select the tag to change to an array tag from the Tags section.
    3. Select the Is Array Tag check box.
    4. Click Update.
  2. Change a tag from the Add Tag Manually window.
    1. In the Tags Maintenance window, click Add Tag Manually.
      The Add Tag Manually dialog box appears.


    2. Select the Collector Name from the list.
    3. Browse for the Source Address by clicking the Browse button ().
    4. In the Data Type field, select the data type.
    5. Select the Is Array Tag check box.
    6. Select the Time Resolution from the list.
    7. Click OK.

Displaying the Last Ten Values of an Array Tag

The Historian Administrator can display the most recent ten values for a selected array tag.
  1. Select the array tag in the Tag Maintenance screen.
  2. Right-click the tag and select Last 10 Values from the menu.
    Each element of the array tag is displayed as a separate row with the tag name and the index as displayed in the following image.

User Defined Data Types

Historian provides you the ability to create user defined data types that include one or more fields and then apply that type to Historian tags. The following sections describe how to work with user defined types:
  • Create a User Defined Type
  • Add Fields to a User Defined Type
  • Modify and Delete Fields in a User Defined Type
  • Modify a User Defined Type
  • Delete a User Defined Type
  • Create a User Defined Type with Multiple Fields
  • Set a Source Address
  • View the Last 10 Values of a MultiField Tag
  • View the Trend of a MultiField Tag
  • Associate a Tag with a User Defined Type
  • Remove a Type from a Tag
When working with User Defined Types, be aware of the following.
  • You need to have appropriate security permissions to create, modify, and delete a user defined type.The type can have its own Administrator security group. For more information on the security rights, refer to the Implementing Historian Security section for the definition of the various security levels and groups.
  • You cannot create an array tag that uses a user defined type.
  • User Defined Types cannot have fields of Scaled or FixedString data types.
  • Scaling, Collector Compression, and Archive Compression does not apply to tags of MultiField datatype.
  • You cannot associate an Enumerated set with a field in a MultiField tag.
  • A MultiField tag supports a maximum of 100 fields.

Creating and Modifying User Defined Types

You can create a user defined type and assign it to multiple tags. A user defined type can have up to 100 fields and must have at least one field.
  1. To create a User Defined Type:
    1. In the Tag Maintenance screen, click Tags > Define User-Defined Types.
      The Define User-Defined Types dialog box appears.
    2. Click Create New Type, or, right-click in the List of User-Defined Types and select Create New Type.
      The User Defined Type Information section is enabled.
    3. In the Type Name field, enter the name of the User Defined Type.
    4. In the Description field, enter the description for the type.
    5. Select the Store Individual Quality check box to store the field level quality.
      If this option is not selected, then the data sample will have a single quality similar to how an array tag works. Storing individual qualities consumes more disk space.
    6. Select the Administer Group from the list.
      This is the Windows Security Group assigned to the user defined type.
    7. Add at least one Field to the User Defined Type.
    8. Click Save Type.
      The following message appears indicating that the save was successful: Your User Defined Type has been successfully saved to the Data Archive.
  2. To add fields to a User Defined Type:
    1. In the Field section of the Define User-Defined Types dialog box, click New Field.
    2. In the Field Name field, enter the name of the field.
    3. If you are using the Master Field functionality, select the Master Field check box to specify a field as the Master Field. Only one field can be the Master Field in a User Defined Type.
    4. In the Field Description field, enter the field description.
    5. Select the Field Data Type from the list.
    6. Click Save Field.
    7. Repeat these steps to create as many fields you want.
  3. To modify fields in a User Defined Type:
    1. In the Define User-Defined Type dialog, select the Field you want to modify from the List of Fields section box.
    2. Modify the details in the Fields section.
    3. Click Save Field.
  4. To delete fields from a User Defined Type:
    1. In the Define User-Defined Type dialog, select the Field you want to modify from the List of Fields section box.
    2. Select the Field you want to delete or, to delete all the fields, click Select All .
    3. Click Delete Field.
  5. To modify a User Defined Type
    Note: You cannot change the name of a user defined type with this process. To change the name of an existing type, right-click it, select Rename Selected Type, and enter the new name in the Type Name field.
    1. Select the type from the List of User Defined Types.
    2. Modify the type description and fields. You cannot modify the name.
    3. Click Save Type.
  6. To delete a User Defined Type
    Note: You cannot delete a User Defined Type if there are tags still using it.
    1. Select the type from the List of User Defined Types.
    2. Right-click and select Delete Selected Type.
  7. To set a source address for a multifield tag:
    1. In the Define User-Defined Type dialog, select the Field you want to modify from the List of Fields section box.
    2. Select the tag and click Browse (...) in the Source Address field.
      The List of Fields dialog appears.


    3. Select the field and click Browse (...) in the Source Address field.
      The Browse For Source Tag dialog appears.
    4. Browse for the tag, click Save Source Address and then click OK.
      The source address for the multifield tag is set.
  8. To view the last 10 values of a multifield tag:
    1. Right-click on a multifield tag (a tag indicated with *) and select Last 10 values.
      The List of Fields dialog appears.


    2. Select the Field from the list and click OK.
      The last ten values of the select field are displayed.
  9. To view the trend of a multifield tag:
    1. Right-click a tag in the Tag Maintenance screen and select Trend.
      The screen displays the trend of data over a selected time period.
    2. Specify the time period and other parameters by clicking Criteria at the bottom of the display.
      The Trend Criteria dialog box appears.
    3. Enter the Start Time and End Time in the appropriate fields or browse to the times and select them.
    4. In the Sampling field, select the data type to use for the display.
      Sampling modes specified with criteria strings take precedence over any mode specified in the Sampling field.
    5. Enter a value for the time interval on the x-axis of the display.
    6. Select the units for the time interval from the drop-down list (seconds, minutes, hours, or days).
    7. Enter the criteria string.
      You can enter the sampling mode, calculation mode, and/or query modifiers in this field.
      Query modifiers are used to specify various ways of retrieving data from Historian. Sampling modes specified with criteria strings take precedence over any mode specified in the Sampling field.
      Request raw data with only good quality by specifying the criteria string: RAWBYTIME#ONLYGOOD
    8. Click OK.
      The display changes in accordance with your criteria.
    You can scroll back and forth on the x-axis time scale by clicking on the single and double left and right arrows at the bottom of the screen. The single arrows move the duration ahead by 50% of the span. The double arrows move the duration ahead by 100% of the span.

Assigning and Removing User Defined Types

There are two ways to assign tags to User Defined Types. User Defined tags are indicated with *in the Tags section. If the desired type is not already created, you can create it while assigning it. You can select multiple tags from the Tags list and assign the same User Defined type to all of them at once.
  1. To assign a User Defined Type to a tag from the Collection tab:
    1. Open the Tag Maintenance screen and click the Collection tab.
    2. Select the tag you wish to associate the User Defined Type from the Tags section.
    3. In the Data Type field, select MultiField.
    4. Click Browse (...) by the User Defined Type field.
      The Define User Defined Type dialog box appears.
    5. From the List of User Defined Types, select the type you want to associate the tag with and click OK.
      If the type has not already been created, create a type now and then continue associating it with the tag. For more information, refer to Create a User Defined Type.
      The modified fields appear in blue color indicating that a type has been selected.
    6. Click Update.
  2. To assign a User Defined Type to a tag from the Add Tag Manually dialog box:
    1. In the Tags Maintenance Window, click Add Tag Manually.
      The Add Tag Manually dialog box appears.
    2. Select the Collector Name from the list.
    3. Browse for the Source Address by clicking the Browse button ().
    4. In the Data Type field, select MultiField.
    5. Select the User Defined Type by clicking the Browse button ().
    6. Select the Time Resolution from the list.
    7. Click OK.
  3. To remove a User Defined Type from a tag:
    1. From the Tags list, select the tag with the user defined type that you want to remove.
    2. Delete the User Defined Type name.
    3. Select a different Data Type from the list.
    4. Click Update.

Creating and Deleting Enumerated Data Sets

An Enumerated Data Set provides an enhanced way of displaying data. It enables you to retrieve numeric data as string state values. The string values can be used in reports or displays.

An Enumerated Data Set contains several states with a set of numeric values and their string display values. You can define enumerated state values such as 0=Manual, 1=Automatic, or 0-100=ON, 101-200=OFF and associate these sets with a tag to retrieve data accordingly.

A Set contains multiple enumerated state values. You can create multiple sets and associate them with multiple tags.

Note: Assigning Enumerated Data Sets to Array tags is not supported.
  1. To create a Set:
    1. In the Tag Maintenance screen, click Tags > Define Enumerated Set.
      The Define Enumerated Set dialog box appears.
    2. Click Create New Set button or right-click in the Set list box and select Create New Set.
      The Set Information section is enabled.
    3. In the Set Name field, enter the name of the set.
    4. In the Description field, enter the description for the set.
    5. Select Single Value or Range as the desired enumeration method. The options in the State section change according to the selection made.
      Select the Single Value option to define a single value for the State. Single value is best used with integer values because they match exactly. Select the Range option to define a range of values for the State. Range value can be used with floating point values because they may not match exactly due to rounding.
    6. Click New State and add a new state.
    7. Click Save Set.
      The following message appears indicating that the save was successful: Your set has been successfully saved to the Data Archiver.
  2. To delete a Set:
    1. Right-click the set you wish to delete and select Delete Selected Set.
  3. To modify a Set:
    1. Select the set that you wish to modify.
    2. Change values as desired.
      You can modify a set's Description and States. You cannot modify the Name of a set. If you do so, the existing name will be overwritten and it is considered a new set.
    3. Click Save Set.

Assigning and Removing Enumerated Sets from Tags

To view data for a tag in an enumerated state value format, assign a set to the tag. You can remove an assigned set from a tag to assign a new tag or not assign any tag at all.
Note: Assigning Enumerated Data Sets to Array tags is not supported.
  1. To assign a set to a tag:
    1. Open the Tag Maintenance screen and click the Collection tab.
    2. From the Tags section, select a Tag.
    3. In the Data Source section, click the Enumerated Set Name field.
      The Define Enumerated Set dialog box appears.
    4. From the List of Enumerated Sets section, select the Set and then click OK.
      The name of the set appears in the Enumerated Set Name field. The Enumerated Set Name field is highlighted in blue indicating that the set has been selected.
    5. Click Update.
      The set is now assigned to the tag and you can view the data in the enumerated state value format.
  2. To remove an assigned set from a tag:
    1. Click in the Enumerated Set Name field.
    2. Delete the set by using the Backspace or Delete key.
      The Enumerated Set Name field is highlighted in blue indicating that a change has been made.
    3. Click Update.

Creating, Modifying, and Deleting Data States

A Data State is the number-string value pair in a Set. Enumerated state values are defined for Data States stored in the Data Archiver. Data is retrieved using the value of the state. You have to define state values within a set to assign enumerated values.
Note: State names can be duplicated. If duplicated states exist, take precautions to avoid unpredictable results. The following example illustrates this.
A tag is associated with an enumerated set defined as follows. The server will return unpredictable results due to the State Name duplication for an input of 2.
State Name State Value
0 Open
1 Close
2 Close
2 Open
  1. To create a State:
    1. In the State section of the Define Enumerated Set dialog box, click New State.
    2. Make a selection in the Enumerate by option.
      If you select Single Value, the State Name, State Value, and Description fields appear. If you select Range, the State Name, Start Range, End Range, and Description fields appear.
    3. Enter the information in the respective fields.
      Enter only numeric values in the State Values field; string values such as ON/OFF are not supported.
    4. Click Save to List to add the state to the set.
  2. To modify a State:
    1. Select the state to modify from the List of States section.
    2. Make the desired changes and click Save to List.
  3. To delete State(s):
    • To delete a single state, select the state and click Delete State.
    • To delete all the states, click Select All , then click Delete State.

Display and Edit Tag Parameters and Options

The fields in the right-hand column of the Tag Maintenance screen allow you to view and edit specific tag parameters and options. To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes.

Action Buttons

Action Buttons

All tabs in the Tag Maintenance screen contain action buttons. Click a button to perform the action indicated by the name. If you want to cancel changes and return to the original values or settings, open a different screen and then return to the Tag Maintenance screen

Button Description
Update Apply all parameter changes you have made on any tabs in this screen.
Delete Delete the selected tag. You can either remove the tag from Historian or just stop collection of data from the tag by clicking the appropriate button and then clicking OK. This action deletes the tag, but does not delete any data for that tag.

General Tab

To display or edit general parameters listed below, click the General Tab. To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue.

Field Description
Description The tag description of the selected tag.
EGU Description The engineering units, if any, assigned to the selected tag.
Comment Comments, if any, that apply to the selected tag.
StepValue This tag property is used to indicate that the actual measured value changes in a sharp step instead of a smooth linear interpolation. This option should only be selected for numeric data. Enabling this option only affects data retrieval; it has no effect on data collection or storage.
Spare Configuration The Spare 1 through Spare 5 fields list any configuration information stored in these fields.

Collection Tab

To display or edit collection parameters, click the Collection Tab. The screen shown in the following figure appears.

To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue.

The fields in the Collection Tab contain the following information:

Table 1. Data Source
Field Description
Collector The name of the collector for the selected tag. Click the drop-down arrow to display a list of all collectors.
Source Address

The address for the selected tag in the data source. Click the Browse button (...) to display a browse window.

Leave the Source Address field blank for Calculation and Server-to-Server tags.

For Python Expression tags, the Source Address field contains the full applicable JSON configuration, which includes an indication of the source address. The Browse button () is disabled for such tags.

Note: When exporting or importing tags using the EXCEL Add-In, the Calculation column, not the SourceAddress column, holds the formulas for the Calculation or Server-to-Server tags.
Data Type A list of data types.
Note: If you change the data type of an existing tag between a numeric and a string or binary data type (and vice versa), the tag's compression and scaling settings will be lost.
Enumerated Set Name The name of the Enumerated Set that can be assigned to the tags. Click the Browse button (...) to display the Define Enumerated Set window.
Data Length The number of bytes for a fixed string data type. This field is active only for fixed string data types. This field is adjacent to the Data Type field.
Is Array Tag Indicates the tag is an array tag.

Choosing a Data Type

The main use of the scaled data type is to save space, but this results in a loss of precision. Instead of using 4 bytes of data, it only uses 2 bytes by storing the data as a percentage of the EGU limit. Changing the EGU limits will result in a change in the values that are displayed. For example, if the original EGU values were 0 to 100 and a value of 20 was stored using the scaled data type and if the EGUs are changed to 0 to 200, the original value of 20 will be represented as 40.
Table 2. Collection Options
Field Description
Collection Select the appropriate option to enable or disable collection for this tag. The default setting is Enabled. If you disable collection for the tag, Historian stops collecting data for the tag, but does not delete the tag or any data.
Collection Type Select the type of data collection used for this tag, which can be polled or unsolicited. Polled means that the data collector requests data from the data source at the collection interval specified in the polling schedule. Unsolicited means that the data source sends data to the collector whenever necessary (independent of the data collector polling schedule).
Collection Interval Enter the time interval between readings of data from this tag. With Unsolicited Collection Type, this field defines the minimum interval at which unsolicited data should be sent by the data source.
Collection Offset Used with the collection interval to schedule collection of data from a tag. For example, to collect a value for a tag every hour at thirty minutes past the hour (12:30, 1:30, 2:30, and so on), enter a collection interval of 1 hour and an offset of 30 minutes. As another example, to collect a value each day at 8am, enter a collection interval of 1 day and an offset of 8 hours.
Note: If you enter a value in milliseconds, the value must be in intervals of 1000 ms. For example, 1000, 2000, and 3000 ms are valid values, but 500 and 1500 ms are invalid. The minimum value is 1000 ms.
Time Resolution Select the precision for timestamps, which can be either seconds, milliseconds or microseconds.

Condition based collection

Condition based collection is a method to control the storage of data for data tags by assigning a condition. Data is always collected but it is only written to the Data Archiver if the condition is true; otherwise, the collected data is discarded.

This condition is driven by a trigger tag; a tag collected by the collector evaluating the condition. Ideally, Condition based Collection should be used only with tags that are updating faster than the trigger tag. Condition based collection can be used to archive only the specific data which is required for analysis, rather than archiving data at all times, as the collector is running.

For example, if a collector has tags for multiple pieces of equipment, you can stop collection of tags for one piece of equipment during its maintenance. It is typically used on tags that use fast polled collection but you don't want to use collector compression. While the equipment is running, you want all the data but when the equipment is stopped, you don't want any data stored. The trigger tag would also typically use polled collection. But, either tag could use unsolicited collection.

The condition is evaluated every time data is collected for the data tag. When a data sample is collected, the condition is evaluated and data is either queued for sending to archiver, or discarded. If the condition cannot be evaluated as true or false, like if the trigger tag contains a bad data quality or the collector is not collecting the trigger tag, the condition is considered true and the data is queued for sending.

No specific processing occurs when the condition becomes true or false. If the condition becomes true, no sample is stored to the data tag using that condition, but the data tag will store a sample next time it collects. When the condition becomes false, no end of the collection marker is stored until the data tag is collected.

For example, if the condition becomes false at 1:15 and the data tag gets collected at 1:20, the end of collection marker will be created at 1:20 and have a timestamp of 1:20, not 1:15.

Condition based collection is supported by only archiver and collectors of Historian version 4.5 and above. Condition based collection does not apply to alarm collectors. This condition based collection is applicable to the following collectors only:
  • Simulation Collector
  • OPC Collector
  • IFIX Collector
  • PI Collector
Table 3. Condition Based Collection
Field Description
Condition Based Select the appropriate option to enable or disable Condition Based Collection for a tag. The default setting is Disabled.
Trigger Tag The name of the tag used in the condition. Use the browse button to select a trigger tag from the list of tags associated with the collector.
Comparison Select the appropriate comparison operator from the drop-down list. Below is the list of comparison operator parameters:
  • Undefined: Collection will resume only when the value of the triggered tag changes. This is considered an incomplete configuration, so condition based collection is turned off and all the collected data is sent to archiver.
  • < =: Setting condition as Trigger Tag value less than or equal to the Compare Value.
  • > = Setting condition as Trigger Tag value greater than or equal to the Compare Value.
  • <: Setting condition as Trigger Tag value less than the Compare Value.
  • >: Setting condition as Trigger Tag value greater than the Compare Value.
  • =: Setting condition as Trigger Tag value equals Compare Value.
  • !=: Setting condition as Trigger Tag value not the same as Compare Value.
Compare Value Enter an appropriate target value to be compared against the value of the Trigger tag. Make sure when using '=' and '!=' comparison parameters that the format of the compared value and triggered tag are the same. For example, for a float type trigger tag, the compare value must be a float value; otherwise, the condition result is an invalid configuration. When the configuration is invalid, condition based collection is disabled and all data is sent to archiver.
End of Collection Markers Select the appropriate option to enable or disable End of Collection markers. The default setting is enabled. This will mark all the tag's values as "Bad", and sub-quality as "ConditionCollectionHalted" when the condition becomes false. Trending and reporting applications can use this information to indicate that the real world value was unknown after this time until the condition becomes true and a new sample is collected. If disabled, a bad data marker is not inserted when the condition becomes false.

Scaling Tab

Scaling converts a data value from a raw value expressed in an arbitrary range of units, such as a number of counts, to one in engineering units, such as gallons per minute or pounds per square inch. The scaled data type can serve as a third form of data compression, in addition to collector compression and archive compression, if it converts a data value from a data type that uses a large number of bytes to one that uses fewer bytes.

To display or edit scaling parameters, click the Scaling tab. The screen shown in the following figure appears.



To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue. The fields in the Scaling tab contain the following information:
Table 4. Engineering Unit Range
Field Description
Hi Engineering Units Displays the current value of the upper range limit of the span for this tag.
Lo Engineering Units Displays the current value of the lower range limit of the span for this tag

Engineering Hi and Lo are retrieved automatically for F_CV fields for iFIX tags; all others are left at default settings. When adding tags from the server using an OPC Collector, the OPC Collector queries the server for the EGU units and EGU Hi/Lo limits. Not all OPC Servers make this information available, however. Therefore, if the server does not provide the limits when requested to do so, the collector automatically assigns an EGU range of 0 to 10,000.

Table 5. Input Scaling
Field Description
Input Scaling Select the appropriate option to enable or disable input scaling, which converts an input data point to an engineering units value.

For example, to rescale and save a 0 - 4096 input value to a scaled range of 0 - 100, you enter 0 and 4096 as the low and high input scale values and 0 and 100 as the low and high engineering units values, respectively.

If a data point exceeds the high or low end of the input scaling range, then Historian logs a bad data quality point with a ScaledOutOfRange subquality. In the previous example, if your input data is less than 0, or greater than 4096, then Historian records a bad data quality for the data point. For instance, a value of 4097, in this example, yields a bad data quality.

Hi Scale Value The upper limit of the span of the input value.
Lo Scale Value The lower limit of the span of the input value.

OPC Servers and TRUE Values

Some OPC Servers return a TRUE value as -1. If your OPC Server is returning TRUE values as -1, modify the following Scaling Tab settings in the Tag Maintenance screen of the Historian Administrator: 
Hi Engineering Units = 0
Lo Engineering Units = 1 
Hi Scale Value = 0 
Lo Scale Value = - 1 
Input Scaling = Enabled

Compression Tab

Note: Array tags do not support Archive and Collector Compression. If the tag is an array tag, then the Compression tab is disabled.

To display or edit compression parameters, click the Compression tab. The screen shown in the following figure appears.



To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue. The fields in the Compression Tab contain the following information:

Table 6. Collector Compression
Field Description
Collector Compression (Enabled, Disabled) Select the appropriate option to enable or disable compression at the collector level.

Collector compression applies a smoothing filter to incoming data by ignoring incremental changes in values that fall within a deadband centered around the last reported value. The collector reports any new value that falls outside the deadband to the Historian archive and then centers the deadband around the new value.
Collector Deadband The current value of the compression deadband. This value can be computed as a percent of the span, centered around the data value or given as an absolute range around the data value.
Note: Some OPC Servers add and subtract the whole deadband value from the last data value. This effectively doubles the magnitude of the deadband compared to other OPC Servers. To determine how your specific server handles deadband, refer to the documentation of your OPC Server.

Example:

The engineering units are 0 to 200. The deadband value is 10%, which is 20 units. If the deadband value is 10% and the last reported value is 50, the value will be reported when the current value exceeds 50 + 10 = 60 or is less than 50 - 10 = 40. Note that the deadband (20 units) is split around the last data value (10 on either side.)

Alternatively, you could specify an absolute deadband of 5. In this instance, if the last value was 50, a new data sample will be reported when the current value exceeds 55 or drops below 45.

If compression is enabled and the deadband is set to zero, the collector ignores data values that do not change and records any that do change. If you set the deadband to a non-zero value, the collector records any value that lies outside the deadband. If the value changes drastically, a pre-spike point may be inserted. See Spike Logic for more details.

Engineering Unit Converts the deadband percentage into engineering units and displays the result. This value establishes the deadband range that is centered around the new value.

When enabling Archive Compression or Collector Compression, the Engineering Units field represents a calculated number created to give an idea of how large a deadband you are creating in Engineering Units. The deadband is entered in % and Historian multiplies that % by the range (Hi Engineering Units - Lo Engineering Units) to compute the % in Engineering Units.
Collector Compression Timeout Indicates the maximum amount of time the collector will wait between sending samples for a tag to the archiver. This time is kept per tag, as different tags report to the archiver at different times.

For polled tags, the Collector Compression Timeout value should be in multiples of your collection interval. After the timeout value is exceeded, the tag stores a value at the next scheduled collection interval, and not when the timeout occurred. For example, if you have a 10 second collection interval, a 1 minute compression timeout, and a collection that started at 2:14:00, if the value has not changed, the value is logged at 2:15:10 and not at 2:15:00.

For unsolicited tags, a value is guaranteed in, at most, twice the compression timeout interval.

A non-changing value would be logged on each compression timeout. For example, an unsolicited tag with a 1 second collection interval and a 30 second compression timeout would be stored every 30 seconds.

A changing value for the same tag may have up to 60 seconds between raw samples. In this case, if the value changes after 10 seconds, then that value is stored, but the value at 30 seconds (if unchanged) will not be stored. The value at 60 seconds will be stored. This leaves a gap of 50 seconds between raw samples which is less than 60 seconds.

Compression timeout is supported in all collectors except the PI collector.

Table 7. Archive Compression
Field Description
Archive Compression (Enabled, Disabled) Select the appropriate option to enable or disable compression at the Historian archive level. If enabled, Historian applies the archive deadband settings against all reported data from the collector.
Archive Deadband The current value of the archive deadband, expressed as a percent of span or an absolute number.

Each time the system reports a new value, it computes a line between this data point and the last archived value. The deadband is calculated as a tolerance centered about the slope of this line. When the next data point is reported, the line between the new point and the last archived point is tested to see if it falls within the deadband tolerance calculated for the previous point. If the new point passes the test, it is reported and is not archived. This process repeats with subsequent points. When a value fails the tolerance test, the last reported point is archived and the system computes a line between the new value and the newly archived point, and the process continues.

Engineering Unit Converts the deadband percentage into engineering units and displays the result. This value establishes the deadband range that is centered around the new value.

When enabling Archive Compression or Collector Compression, the Engineering Units field represents a calculated number created to give an idea of how large a deadband you are creating in Engineering Units. The deadband is entered in % and Historian multiplies that % by the range (Hi Engineering Units - Lo Engineering Units) to compute the % in Engineering Units.
Archive Compression Timeout Indicates the maximum amount of time from the last stored point before another point is stored, if the value does not exceed the archive compression deadband.

The data archiver treats the incoming sample after the timeout occurs as if it exceeded compression. It then stores the pending sample.

Notes on Collector and Archive Compression

Note: Array tags do not support Archive and Collector Compression. If the tag is an array tag, then the Compression tab is disabled.

This section describes the behavior of collector and archive compression. Understanding these two Historian features will help you apply them appropriately to reduce the storage of unnecessary data. Smaller archives are easier to maintain and allow you to keep a greater time span of historical data online.

Collector Compression

Collector compression applies a smoothing filter, inside the collector, to data retrieved from the data source. By ignoring small changes in values that fall within a deadband centered around the last reported value, only significant changes are reported to the archiver. Fewer samples reported yields less work for the archiver and less archive storage space used.

The definition of significant changes is determined by the user by setting the collector compression deadband value. For convenience, the Historian Administrator calculates and shows the deadband in engineering units if you enter a deadband percentage. If you later change the high and low EGU limits, the deadband is still a percentage, but of the new limits. A 20% deadband on 0 to 500 EGU span is 100 engineering units. Then, you change the limits to 100 and 200 and the 20% is now 20 engineering units.

The deadband is centered around the last reported sample, not simply added to it or subtracted. If your intent is to have a deadband of 1 unit between reported samples, you want a compression deadband of 2 so it is one to each side of the last reported sample. In an example of 0 to 500 EGU range, with a deadband of 20%, the deadband is 100 units, and the value has to change by more than 50 units from the last reported value. Changes in data quality from good to bad, or bad to good, automatically exceed collector compression and are reported to the archiver. Any data to that comes to the collector out of time order will also automatically exceed collector compression.

It is possible for collected tags with no compression to appear in Historian as if the collector or archive compression options are enabled. If collector compression occurs, you will notice an increase in the percentage of the Compression value from 0% in the Collectors panel of the System Statistics screen in the Historian Administrator. When archive compression occurs, you will notice the Archive Compression value and status bar change on the System Statistics screen.

For all collectors, except the File Collector, you may observe collector compression occurring for your collected data (even though it is not enabled) if bad quality data samples appear in succession. When a succession of bad data quality samples appears, Historian collects only the first sample in the series. No new samples are collected until the data quality changes. Historian does not collect the redundant bad data quality samples, and this is reflected in the Collector Compression percentage statistic.

For a Calculation or Server-to-Server Collector, you may possibly observe collector compression (even though it is not enabled) when calculations fail, producing no results or bad quality data. The effect of Collector Compression Timeout is to behave, for one poll cycle, as if the collector compression feature is not being used. The sample collected from the data source is sent to the archiver. Then the compression is turned back on, as configured, for the next poll cycle with new samples being compared to the value sent to the archiver.

Archive Compression

Archive compression can be used to reduce the number of samples stored when data values for a tag form a straight line in any direction. For a horizontal line (non changing value), the behavior is similar to collector compression. But, in archive compression, it is not the values that are being compared to a deadband, but the slope of line those values produce when plotted value against time. Archive compression logic is executed in the data archiver and, therefore, can be applied to tags populated by methods other than collectors.

Archive compression can be used on tags where data is being added to a tag by migration, or by the file collector, or by an SDK program for instance. Each time the archiver receives a new value for a tag, the archiver computes a line between this incoming data point and the last archived value.

The deadband is calculated as a tolerance centered about the slope of this line. The slope is tested to see if it falls within the deadband tolerance calculated for the previous point. If the new point does not exceed the tolerance, it is held by the archiver rather than being archived to disk. This process repeats with subsequent points. When an incoming value exceeds the tolerance, the value held by the archiver is written to disk and the incoming sample becomes held.

The effect of the archive compression timeout is that the incoming sample is automatically considered to have exceeded compression. The held sample is archived to disk and the incoming sample becomes the new held sample. If the Archive Compression value on the System Statistics screen indicates that archive compression is occurring, and you did not enable archive compression for the tags, the reason could be because of internal statistics tags with archive compression enabled.

Calculation Tab

Note: The Calculation Tab applies only to Calculation and Server-to-Server tags. The Calculation Tab is disabled for array tags.

To display calculation parameters, click the Calculation Tab.

The screen shown in the following figure appears.



To modify the calculation formula, enter new values in the appropriate fields and then click Update at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue.

Calculation Pane

The Calculation pane is where you build your calculation formula. You can either type the VB Script directly or use the Insert Function Wizard. See Building Calculation Formulas Using the Wizard for more information. Calculation Triggers defines the appropriate trigger for all tags that have a Collection Type set to Unsolicited rather than Polled.

There are several buttons associated with the Calculation pane.
  • The Wizard, Tag, and Time buttons are associated with the Insert Function Wizard and allow you to use the wizard to directly populate syntax within the Calculation pane.
  • The Test button allows you to verify the syntax within your calculation formula.
  • Use the Clear button to clear the Calculation pane.
  • The Window button expands the Calculation pane.

Advanced Tab

To display or edit advanced parameters, click the Advanced Tab.

The screen shown in the following figure appears.



To modify the values, enter new values in the appropriate fields and then click the Update button at the bottom of the screen to apply the changes. Until you click the Update button, entering a new value changes the display of the field name to blue.

The fields in the Advanced tab contain the following information:

Table 8. Data Collection Options
Field Description
Time Assigned By The source of the timestamp for a data value is either the collector or the data source.
Note: This field is disabled for Calculation and Server-to-Server tags.

All tags, by default, have their time assigned by the collector. When you configure a tag for a polled collection rate, the tag is updated based on the collection interval. For example, if you set the collection interval to 5 seconds with no compression, then the archive will be updated with a new data point and timestamp every 5 seconds, even if the value isn't changing.

However, if you change the Time Assigned By field to Source for the same tag, the archive only updates when the device timestamp changes. For example, if the poll time is still 5 seconds, but if the timestamp on the device does not change for 10 minutes, no new data will be added to the archive for 10 minutes.
Time Zone Bias The number of minutes from GMT that should be used to translate timestamps when retrieving data from this tag. For example, the time zone bias for Eastern Standard time is -300 minutes (GMT-5).

This property is not used during collection. Use this option if a particular tag requires a time zone adjustment during retrieval other than the client or server time zone. For example, you could retrieve data for two tags with different time zones by using the tag time zone selection in the iFIX chart.

Time Adjustment If the Server-to-Server Collector is not running on the source computer, select the Adjust for Source Time Difference option to compensate for the time difference between the source archiver computer and the collector computer.
Note: The Time Adjustment field only applies to Server-to-Server tags that use a polled collection type.
Data Store Displays the Data Store the tag belongs to.
Note: DRAFT COMMENT: Implementing Historian Security is external link, please resolve.
Refer to Implementing Historian Security for definitions of the various security levels and groups.
Table 9. Security
Field Description
Read Group The Windows security group assigned to the selected tag. Refer to Implementing Historian Security for definitions of the various security levels and groups.
Write Group The Windows security group assigned to the selected tag.
Administer Group The Windows security group assigned to the selected tag.
Table 10. Audit
Field Description
Last Modified The date the last tag parameter modification was made.
Modified By The name of the person who last modified the tag configuration parameters.