Issue
Automation Server -Trend does not record at time interval when it is stopped and restarted by AS power cycle or reboot.
Trend log cycle is thrown off when the trend is stopped and started again due to an AS power cycle or reboot. For example, an Interval Trend Log set up to log ever 15 minutes with an activation time right on the hour (1:00, 1:15, 1:30 etc.) that lost power for a while would start logging as soon as the power was restored (this might be 2:07, 2:22, 2:37 etc. for example).
UPDATE:
This issue has been corrected in SBO version 1.5, any SBO version 1.5 or grater will synchronize the interval log to the clock.
Product Line
EcoStruxure Building Operation
Environment
- Automation Server
- Struxureware Workstation
Cause
This is how Interval Trends behave. For interval trending based on the time a different approach must be taken.
UPDATE:
This issue has been corrected in SBO version 1.5, any SBO version 1.5 or grater will synchronize the interval log to the clock.
Resolution
Rather than using Interval Trend Logs use Variable Triggered Trend Logs and trigger them using the following method:
- Create a new binary value and a new function block program. The value will serve to trigger the Variable Triggered Trend Logs. The program will set the trigger variable based on a certain time interval (for example on the hour, 15 minutes, 30 minutes and 45 minutes).
- Edit the program and configure it as seen in the image below. This include an integer input, an expression that will evaluate the minutes attribute of the AS and a binary output. You can also download an export of the program and value here.
- Bind the input of the program to the minutes attribute of the Automation Server and the output to the trigger value that you created. Note that you should also bind the Task to Task 1 (100 ms) for best performance.
- Create your Variable Triggered Trend Logs on the points that you want to trend. Do this by right-clicking the point to trend and selecting New > Trend and then in the dialog select Variable Triggered Trend Log.
- Click Next and then set the Trigger Variable to the value that you created. Make sure Trigger when is set to Change to true.
Note that this example will create a log at 0, 15, 30 and 45 minutes past the hour. You can modify the program to trigger only every hour, every half hour or however you want.
