Collector Configuration - Common Fields

This topic provides a list of general fields that you can configure for any collector instance. These fields appear in the DETAILS section when you select a collector instance. For fields specific to a cloud destination, refer to Alibaba Cloud, AWS Cloud, Azure Cloud, Google Could, and Predix Cloud. For fields specific to the collector type, refer to the topics on adding and configuring each individual collector.

After you enter/modify a value in these fields, the changes are saved automatically after you place the cursor in a different field. Until the changes are saved, the values appear in bold formatting.

Table 1. The General Section
Field Description
Collector Name The name of the collector instance. This field is disabled.
Collector Type The type of the collector instance. This field is disabled.
Description The description of the collector instance. This field is disabled.
Memory Buffer Size (MB) The size of the memory buffer currently assigned to the store-and-forward function. The memory buffer stores data during short-term or momentary interruptions of the server connection; the disk buffer handles long duration outages. To estimate the size you need for this buffer, you need to know how fast the collector is trying to send data to the server and how long the server connection is likely to be down. With those values and a safety margin, you can compute the required size of the buffer.

The default value is 20.

Minimum Free Space (MB) The minimum free disk space that must be available on the computer. If the minimum space required is not available when the collector starts, the collector will shut down.
Total Events Collected This field is disabled.
Total Events Reported This field is disabled.
Table 2. The Tags section
Field Description
Tag Prefix The prefix that will be added to each tag that you configure for the collector instance. This field is disabled and populated with the name of the collector instance.

This field applies to all collectors except File and Calculation collectors.

Collection Interval Value The interval at which the collector collects data for all the tags configured in the collector instance.
  • For polled data collection, this value represents the time required to complete a poll of tags in the collector.
  • For unsolicited data collection, it represents the frequency at which data is retrieved from tags in the collector. The collection interval can be individually configured for each tag.
You can set this value for each tag as well.
Important: For an OPC collector, to avoid collecting redundant values when using device timestamps, specify a collection interval that is greater than the OPC server update rate.
Collection Interval The units of measure for the collection interval value.
Collection Type The type of the data collection:
  • Polled: Data is collected based on a scheduled time interval. This type of data collection is supported only for:
    • The Calculation collector
    • The HAB collector
    • The iFIX collector
    • The OPC Classic DA collector
    • The OPC UA DA collector
    • The Simulation collector
    • The Windows Performance collector
  • Unsolicited: Data is collected based on an event. This type of data collection is supported only for:
    • The Calculation collector
    • The HAB collector
    • The MQTT collector
    • The ODBC collector
    • The OPC Classic DA collector
    • The OPC Classic HDA collector
    • The OPC UA DA collector
    • The OSI PI collector
    • The OSI PI distributor
    • The Server-to-Server collector
    • The Server-to-Server distributor
    • The Wonderware collector
Time Assigned By Indicates whether the timestamp for the collected data is set based on the data source or the collector. For example, for an OSI PI collector, if you select Source, the timestamp of the OSI PI server is considered for the values collected by the collector. If you select Collector, the timestamp of the collector is considered.
Table 3. The Collector Compression Section
Field Description
Collector Compression Indicates whether you want to apply collector compression, which is a smoothing filter 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 stored in Historian, thus consuming less archive storage space.

For more information, refer to Notes on Collector and Archive Compression.

Deadband Indicates whether you want to apply a deadband based on the percentage of values or on absolute values.
For example, if you set the deadband to 20% for a range of 0 to 500 engineering units, the deadband value is 100 units, which is 50 units on each side. Therefore, only if the difference between two values is greater than 50, they are stored in Historian.
Note: If the data quality changes from good to bad or vice versa, the values are stored in Historian regardless of the deadband value.
Deadband Value The deadband value that you want to use for values collected by the collector. Depending on whether you have selected percent or absolute, the deadband value is determined.

For example, if you want to set a deadband of 5 units on either side of a value (that is, value +/- 5), enter 10 in the Deadband Value field, and select Absolute in the Deadband field. Similarly, if you want to set a deadband of 5% on either side of a value, enter 10 in the Deadband Value field, and select Percent in the Deadband field.

For more information, refer to Notes on Collector and Archive Compression.

Compression Timeout The time for one poll cycle for which collector compression is not used, thus sending all the samples to Historian.

This is used for a Calculation collector or Server-to-Server collector, when calculations fail, you may possibly observe collector compression (even if it is not enabled), thus producing no results or bad quality data. In such cases, you can use compression timeout, thus sending all the samples to Historian.

For more information, refer to Notes on Collector and Archive Compression.

Compression Timeout Interval The units of measure for compression timeout.
Spike Logic Control Indicates whether you want to apply spike logic to tag values. When you apply spike logic, in the event of a sudden change in tag values, a data sample is inserted just before the spike. The timestamp of the inserted sample is determined by your polling interval. If samples are collected at 1 second intervals, the inserted sample's timestamp will be 1 second before the spike. This helps clearly identify the spike, and retains a more accurate picture of the data leading up to it.

For more information, refer to Spike Logic.

Multiplier Specifies how much larger a spike value must be than the deadband range before the spike logic is invoked.

For example, if you enter 3 in the Multiplier field, and the deadband is set to 5%, the spike logic will not be invoked until the difference between the spike value and the previously archived data point is 15% of the EGU range.

Interval Specifies how many samples must have been compressed before the spike logic is invoked. For example, if you enter 4 in the Interval field, and 6 values have been compressed since the last archived data sample, the spike logic will be invoked.
Table 4. The Collector Options Section
Field Description
Online Tag Configuration Changes Indicates whether you want tag configuration changes to reflect immediately. If you disable this option, any tag configuration changes will reflect only after you restart the collector instance.
Browse Source Address Space Indicates whether you want to allow browsing for tags in the source. You may sometimes want to disable this option to reduce processing load on the collector.
Synchronize Timestamps to Server Indicates whether you want to adjust the timestamp of data to align with the time setting in the Historian server. Note that this does not change the time setting in the collector machine; it only calculates the timestamp based on the difference between the time settings in the server machine and the collector machine, independent of time zone or daylight saving differences.
Note:
  • This option is applicable only if the timestamp of the collector is considered (instead of that of the data source - as specified in the Time Assigned By field).
  • If this option is disabled, and if the time in the collector machine is more than 15 minutes ahead of the time in the server machine, data will not be stored in Historian.
Delay Collection at Startup (sec) The duration, in seconds, after which you want the data collection to begin post tag configuration.
Table 5. The Advanced Section
Field Description
Debug Mode The debug mode for collector logs. 0 indicates normal log level, whereas 255 indicates that debugging is enabled.
Note: Leaving the debug mode enabled for a long time consumes disk space.
Message Compression Indicates whether you want to apply message compression.
Table 6. The Collector Status Output Section
Field Description
Rate Output Address

The address in the source database into which the collector writes the output of events/minute. This will help an operator (or a HMI/SCADA application) learn the performance of the collector. Values are captured once a minute.

You must enter the address of a writable analog field.

For example, for an iFIX collector, enter the address of an iFIX tag in the following format: <node name>.<tag name>.<field name> (for example, MyNode.MySIM_AO.F_CV).

Status Output Address

The address in the source database into which the collector writes the current value of its status (for example, running, stopped). This will help an operator (or a HMI/SCADA application) learn the current status of the collector. The value is updated only if the status of the collector changes.

You must enter the address of a writable text field of at least eight characters.

For an iFIX collector, use TX tag for the output address. Enter the address in the following format: <node name>.<tag name>.<field name> (for example, MyNode.MyCollector_TX.A_CV).

Heartbeat Output Address

The address in the source database into which the collector writes the heartbeat signal output. Values are captured once a minute.

You must enter the address of a writable analog field.

For an iFIX data collector, use an iFIX tag for the output address. Enter the address in the following format: <node name>.<tag name>.<field name> (for example, MyNode.MyCollector_TX.A_CV).

You can program the iFIX database to generate an alarm if values are not written every minute, notifying you that the collector has stopped.