Applies To:
  • CitectSCADA 3.xx, 4.xx, 5.xx

I have configured an Accumulator, but it does not function as expected. What might be the problem? 

Accumulators are processed on the Reports Server, hence you must have a Reports Server enabled on your standalone PC or Citect network. If you have configured a redundant Reports Server then the Accumulator will start running on the Standby if the Primary becomes unavailable.

Rather than writing the run time, number of starts and totalised values down to a physical I/O Device, you may choose to store them in a Disk I/O Device in order to conserve bandwidth. In this event, on a networked installation we recommend configuring a redundant Disk Device. This is of particular importance if your Disk PLC resides on your Primary Report Server and you want to ensure the Standby Reports Server can obtain the current Accumulator values when it begins processing.

The Accumulators processing and display characteristics are determined by the parameters [Accumulator]WatchTime and [Accumulator]UpdateTime as described in on-line help. These maybe set in either the Citect.ini file or the Projects Parameters Database. As with all Citect parameter settings, the Citect.ini values will override any settings in the local database. The default setting for the UpdateTime is 600 seconds. This has been set high to minimise bandwidth when writing to an external I/O Device. If you are utilising a Disk I/O Device then this is not so critical. Depending upon the cruciality of your data, you may choose to decrease this parameter significantly. A default of 60 seconds has been set for the [Accumulator]WatchTime. As this trigger bit will usually be read from a physical device, set this parameter to the largest acceptable value possible. If you believe your WatchTime parameter is having no effect, then go to Page Table Stats in the Citect Kernel and view the Avg time for Acc Trigger. (in Citect V5.01 onwards) If this differs from what you believe your WatchTime is set too, then check your Citect.ini file or better still, use on-line help to interactively set the Watchtime parameter.

Remember that the above parameters must be configured on your Reports Server. (and the standby reports server if one exists)