Why are there gaps in my PC-logged data for basic power meter/custom MDI devices?



There are gaps in my PC-logged data for basic power meter/custom MDI devices?

Product Line
ION Enterprise
Struxureware Power Monitoring
Power Monitoring Expert

Modbus Device Importer

Many third-party/basic power meter devices added to Management Console have no on-board logging. It is possible to set PC-based logging up within the MDI for the device.
The following update settings in the MDI translators can cause such behavior even if there are no communication issues with the device. 

HighSpeedUpdateRate (.xml) 

  • for polling for calculations and logging
  • If only logging (no calculations) can be set to 300
  • For calculations (min/max/avg) needs to be more frequent - 30 
LowSpeedUpdateRate (.xml)
  • for configuration change detection
Staleness Threshold (.ion)
  • if HighSpeedUpdateRate is changed, the Staleness Threshold also needs to be changed to be 2.5 times HighSpeedUpdateRate – only for Data Rec 1 – all other Data Recs will pick up this setting

Below is an example with the PM200/PM700 meters which will describe this process:

By default, the HighSpeedUpdate in the .xml files for these devices is set to 300 seconds. However, the data recorder's staleness threshold, defined in the default .ion file is only 120 seconds. The staleness threshold should be set to be a little more than double the HighSpeedUpdate, so that a single communications error won't cause problems (i.e. it can fall back to the previous value). By default, the opposite is occurring, so we're probably going to see gaps regardless of communication errors.

In order to prevent gaps in the data, the staleness threshold should be set to 750 seconds (i.e. 2.5 x HighSpeedUpdate). This can be done by directly editing the .ion file for the device. Look for the "RE1 Staleness Threshold" registers for all PC-based data recorders in the .ion file, and change the t:V child element's value from 120 to 750. Be sure to edit the version of the file that is located in the \config\translators directory, which is where it will get saved after configuring the logging in the MDI.

The steps to configure logging in the MDI to avoid gaps in the data are as follows:
1. Open the appropriate driver files in the MDI and configure the logging as desired.
2. Once the logging has been configured, choose 'Save', then choose 'Update Device Type' from the MDI menu, then close the MDI.
3. Find the PM200.ion or PM700.ion file in the \config\translators, and open the file in Notepad.
4. Search for Staleness Threshold (each Data Recorder will have this setting), which you can locate below the <t:V>100</t:V>> element. Change the value in the Staleness Threshold from 120 to 750 for Data Rec 1 (all other Data Recs will pick up this setting)
5. Save and close the file