FAQ - frequently asked questions and answers

In this section frequently asked questions are answered, in order to facilitate your work with the TwinCAT Analytics Storage Provider (ASP). If you have any further questions, please contact our support team at support@beckhoff.com.

How can I manage the table schema of MS SQL with ASP?

You don't have to worry about the table schema. This is done completely by the Analytics Storage Provider. You only have to specify on which database server the data should be stored. If you want to see data in your own table structure, you have to stream the data into a TwinCAT Analytics Runtime and have the TwinCAT Database Server write the data in your structure.

Can I control the Storage Provider in a programmable way?

Yes, via the PLC interface for the TwinCAT Storage Provider. You can start/stop recordings or retrieve historical data (raw data or result data).

Is it also possible to save results from the Analytics Runtime?

Yes, this is possible. For this purpose, you can choose to send the results to an MQTT Message Broker when generating the Analytics Runtime from the Analytics Workbench configurator. This data stream can be captured by the Storage Provider.

Are open source software components used in TwinCAT Measurement products?

Yes, various open source components are used.

Please see the information on the page Third-party components.

What factors influence the data throughput of the storage provider?

The data throughput depends on many influencing variables. Primarily of system and network resources. An overview:

System properties (CPU, RAM)
Writing speed and quality of the storage medium (SSD)
Network properties
Complexity of symbolism (data type, structures, arrays, etc.)
Mode of historization (total symbolism allows higher throughput, a subset may be more costly depending on its size)
Compression level of the stream (the stronger the compression, the higher the system load)
The size of a sample
Total size of a data packet (number of samples per packet)
The number of parallel recordings that the storage provider manages

How do I configure my local Mosquitto MQTT message broker so that remote systems can send/receive data?

In the default configuration, Mosquitto only allows connections from localhost. To allow connections from other systems, add the following lines to mosquitto.conf:

•    listener 1883 0.0.0.0

•    allow_anonymous true

Then restart the Mosquitto service. If problems continue to occur, please check the settings in your firewall.

Notice

Secure external access

Please note that the broker is enabled for anonymous access as a result of these changes. A more secure option is to use access data (user name/password) and/or certificates. Alternatively, you can define listeners for specific IP addresses and thus restrict external access.

Why does the storage provider start but the storages do not?

Check whether a valid storage provider license is activated. The individual Storages will not start without an activated license.

Why do I get the exception "STL: Memory allocation" when starting the PLC?

One probable cause is insufficient router memory. Increase the allocated memory to at least 64 MB, preferably 128 MB.

What can I do if the TwinCAT Storage Provider is reporting an increasing number of connection issues?

The TwinCAT Storage Provider communicates via MQTT. If you experience connection issues, you can adjust the parameters for communicating with the MQTT brokers in the designated file, ConnectionParameters.xml:

External_communication_timeout_100ns: Communication timeout [100 ns]
External_keep_alive_period_100ns: Keep-alive interval [100 ns]
External_buffer_size_in_Bytes: TCP buffer size in bytes

By default, the file is located in the ASP installation’s configuration folder:

Windows: C:\ProgramData\Beckhoff\TwinCAT\Functions\TF3520-Analytics-StorageProvider\Configurations

Linux^®/TC-BSD: /etc/TwinCAT/3.1/Functions/TF3520-Analytics-Storage-Provider/Configurations/ConnectionParameters.xml

If the file does not exist, the TwinCAT Storage Provider automatically creates a new file with default values the next time it starts.

To adjust the parameters, stop the Storage Provider service and open ConnectionParameters.xml in a text editor. There, you can adjust the desired values and save the document. The changes will take effect the next time the Storage Provider service is restarted.