Configure General Collector Options
You can modify collector configurations from the following sections of the Collector Configuration Screen.
- Action Buttons
- Configuration Tab
- Defaults Tab
- Performance Tab
- Redundancy Tab
Action Buttons
| Button | Action |
|---|---|
 | Resumes collection of the collector. |
 | Pauses the collection of the collector |
 | Refreshes the screen |
| Update | Updates the changes made. |
Performance Tab
| Field | Description |
|---|---|
| Report Rate | This display is a trend chart that displays the average rate at which data is coming into the server from the selected collector. This is a general indicator of load on the Historian collector. Since this chart displays a slow trend of compressed data, it may not always match the instantaneous value of Report Rate displayed in the Collector panel of the System Statistics screen. |
| Out of Order | The number of samples within a series of timestamped data values normally transmitted in sequence that have been received out of sequence since collector startup. This field applies to all collectors. |
| Compression | This display is a trend chart that displays the effectiveness of collector compression. If the chart displays a low current value, you can widen the compression deadbands to pass fewer values and increase the effect of compression. |
| Total Events Collected | Displays the number of events collected from the data source. |
| Total Events Reported | Displays the total number of events reported to the Historian archive from the collector. |
| Overruns | This trend chart displays the value at which data overruns are occurring. This value is calculated by following equation: OVERRUN_PCT =OVERRUNS / ( OVERRUNS + TOTAL_EVENTS_COLLECTED ) Overruns are a count of the total number of data events not collected. Under normal conditions, the current value should always be zero. If the current value is not zero, which indicates that data is being lost, you should take steps to reduce peak load on the system by increasing the collection interval. |
Defaults Tab
The Defaults tab displays the information related to tags and the collectors. The following table explains the fields in detail:
| Field | Description |
|---|---|
| Prefix for Tag Names | Displays a prefix, if any, that is automatically added to all tag names when you browse and pick the specified collector. To change the prefix, enter a new text string and click the Update button at the bottom of the screen. This field applies to all collectors except the File and Calculation Collectors |
| Collection Type | Indicates whether this collector is configured for polled data collection or unsolicited collection. |
| Collection Interval | The time in milliseconds, seconds, minutes, or hours required to complete a poll of a given tag on the selected collector. It is also used in unsolicited collection. In effect, it specifies how frequently data can be read from a tag. The collection interval can be individually configured for each tag. To change it, enter a new value. NOTE: To avoid collecting repeat values with the OPC Collector when using device timestamps, specify a collection interval that is greater than the OPC Server update rate. |
| Time Assigned By | Indicates whether the timestamp for the data value is supplied by the collector or the data source. To change it, select a different type. |
| Compression Indicates whether or not collector compression is enabled as a default setting. To change it, select the other option. This option is overridden by Tag settings. | |
| Deadband | The default setting of the collector compression deadband in absolute or percentage range values. |
| Timeout | The default setting for the collector compression time-out for tags added through the Add Multiple Tags From Collector dialog box. You must enable the Collector Compression option to use this field. |
| Spike Logic Control | Spike logic monitors incoming data samples for spikes in a tag's values. If spike logic is enabled, a sample of equal value to the previously archived sample is inserted into the archive in front of the spike value. |
| Multiplier | The Multiplier option specifies how much larger a spike value must be than the deadband range before spike logic is invoked. For example, if a value of 3 is entered in the Multiplier field and the deadband percentage is set to 5%, 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 | The Interval option specifies how many samples must have been compressed before spike logic is invoked. For example, if the Interval field is set to 4, and 6 values have been compressed since the last archived data sample, spike logic will be invoked. |
| On-Line Tag Config Changes | Enabling this feature allows you to make on the fly changes to tags without having to restart the collector. If you disable this option, any changes you make to tags do not affect collection until you restart the collector executable. |
| Sync Timestamp for Server | Enabling this feature automatically adjusts all outgoing data timestamps to match the server clock. This feature is not active when you configure timestamps to be supplied by the data source. Note, that this does not change collector times to match the server time, it adds or subtracts an increment of time to compensate for the relative difference between the clocks of the server and collector, independent of time zone or day light saving time (DST) differences. If the collector system clock is greater than 15 minutes ahead of the archiver system clock, and the Synchronize Timestamps to Server option is disabled, data will not be written to the archive. |
| Delay Collection @ Startup (Sec) | Permits you to enter the number of seconds to delay collection on startup (after loading its tag configuration). The default is 2 seconds. |
Configuration Tab
| Field | Description |
|---|---|
| Description | The name of the selected collector. |
| Number of Tags | Displays the number of tags currently added to the Simulation Collector. Edit this field to modify the number of Simulation tags available for addition to the Historian System. |
| Function Period (Seconds) | The period, in seconds, of the SIN, STEP, and RAMP functions implemented in the Simulation collector. The default is 60 seconds. |
| Computer Name | The machine name of the computer that the collector is installed on. |
| Memory Buffer Size | 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 calculate the required size of the buffer. NOTE: If you enter a new value for this parameter, the change is effective the next time you restart the collector. |
| Minimum Free Space | 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. |
| Heartbeat Output Address | The address in the source database into which the collector writes the heartbeat signal output. This address should be connected to a writable analog field. For an iFIX data collector, use an iFIX tag for the output address. Enter the address as NODE.TAG.FIELD (for example, MyNode.MyCollector_AO.F_CV). For an OPC Collector, use the OPC address in the server. Refer to your OPC documentation for more information. The data collector writes the value of 1 to this location every 60 seconds while it is running. You could program the iFIX database to generate an alarm if the Heartbeat Output Address is not written to once every 60 seconds, notifying you that the data collector has stopped. |
| Status Output Address |
Address in the source database into which the collector writes the current value of the collector status (running, stopping, stopped, unknown, or starting) output, letting an operator or the HMI/SCADA application know the current status of the collector. This address should be connected to a writable text field of at least 8 characters. This value is updated only upon a change in status of the collector. For an iFIX data collector, use a TX tag for the output address. Enter the address as NODE.TAG.FIELD (for example, MyNode.MyCollector_TX.A_CV). For an OPC Collector, use an OPC address in the server. Refer to your OPC documentation for more information. The text string usually displays Running, Stopped, or Unknown, matching the Status column value displayed in the collector pane in the System Statistics screen of the Historian Administrator. |
| Rate Output Address |
The address in the source database into which the collector writes the current value of the events/minute output, letting an operator or the HMI/SCADA application know the performance of the collector. This should be connected to a writable analog field. The value is written once per minute. For an iFIX data collector, use an iFIX tag for the output address. Enter the address as NODE.TAG.FIELD (for example, MyNode.MySIM_AO.F_CV). For an OPC Collector, use a writable OPC address in the server. Refer to your OPC documentation for more information. This value displays the same value as the Report Rate field in the collector pane in the System Statistics screen of the Historian Administrator. |
Redundancy Tab
Historian includes support for collector redundancy, which decreases the likelihood of lost data due to software or hardware failures. Implementing collector redundancy ensures that collection of your data remains uninterrupted. Collector redundancy makes use of two or more collectors, gathering data from a single source. Two or more collectors may be configured in a redundant group. All collectors in the group actively gather the same tags from a data source but only the "active" collector forwards its samples to the Historian server. The non-active collectors buffer their data against failover of the active collector. The Historian server actively monitors the health of the redundant collectors and will automatically switch to a backup if certain user-configurable trigger conditions are met.
| Field | Description |
|---|---|
| Backup Collector | If enabled, specifies that this is a redundant collector. |
| Backup For | Specifies the primary collector. Note: This configuration will be preserved if you disable collector redundancy. This allows you to temporarily take a redundant collector offline without losing its configuration. |
| Backup Collector Status | The current status of this collector. |
| Backed Up By | The name of the collector providing redundancy for the selected collector. |
| Watchdog Tag | Specifies a tag to use to determine the status of the collector. If the watchdog tag meets any of the conditions specified below, the secondary collector will be brought on line to replace it. |
| Failover on Bad Quality | If enabled, the secondary collector is promoted when a data sample from the watchdog tag is received with bad quality. Failover happens on every write of a bad data sample to the watchdog, not just on the transition from good to bad quality |
| Failover When Value Transitions from Zero | If selected, the secondary collector is promoted when a data sample from the watchdog tag with a non-zero value is received from the primary collector. Failure happens every time a non-zero value is received, not just when the value promotes from zero to a non-zero value |
| Failover When No Value Changes for __ Seconds | If selected, the secondary collector is promoted when no data value changes have been received within the time period specified. This could be tied into a heartbeat status indicator where the value is checked every 5 seconds. To prevent failure, there must be a value change. |