The Datalogs application lets you create up to 16 datalogs. Each datalog can log up to 8 values. Each value in a datalog can be either a digital value, an integer value, a floating point value or a time stamp.
For integer and floating point values, a function like minimum, maximum or average can be applied to the data before it is logged.
Each datalog can be configured to log periodically, or on demand, via coil. Logging can be as fast as every 5 seconds, and each log can be configured to hold up to 16384 entries.
The RTU does not have enough memory to create 16 fully sized datalogs, where each datalog has 16384 entries and holds 8 values. Configure datalogs carefully and verify that they are created correctly before putting the RTU into service.
The application's diagnostic log contains detailed information on the status of datalogs.
Program Execution
When a Datalogs application configuration is changed, the application checks the configuration of each datalog to see if the log should be enabled. If the log should be enabled, the current configuration of the datalog is checked against the desired configuration. If the desired configuration is different than the current configuration of the datalog, the datalog will be deleted and created with the desired configuration.
Changes to the configuration of a datalog (the number of logged values, the types of values or the number of records) will cause the datalog to be deleted and recreated. This will result in all data in the log being deleted.
Changes to the polling rate will not cause the datalog to be deleted and recreated, assuming that the rest of the configuration matches the current configuration.
If a datalog was previously enabled, and successfully created, and then subsequently disabled, the log will only be deleted if it was created by the Datalogs application. This prevents the accidental deletion of logs created in ladder logic.
The Datalogs application can monitor up to 32 digital values, 32 integer values, and 32 floating point values. Use the Values to Log configuration groups to configure which values to log.
