Handling “Late Data” into a historian can be tricky when that data changes over time.
For example, we have a situation where material arrives in a truck on a weighbridge for processing. A sample is taken and sent to a laboratory for composition analysis but in order that the process can continue without waiting for the lab results, estimates are made and stored in the historian for temporary use.
After some time, once analysis has taken place, the actual values then replace the initial values (and the temporary historian entries for that timestamp must be updated) so that more accurate calculations on the given data can be performed.
This back-tracking and synchronisation of historical data and more have been incorporated into our IDX Listener technology to allow for efficient handling of these ‘late data’ into a historian.