About OPC UA Client Connection and Communication
Recommended settings regarding connection timeout (Connect Timeout)
When connecting from an OPC UA client to this product, it is recommended to set the connection processing timeout (Connect Timeout) to 30,000 ms (30 seconds) or more.
Especially when using encrypted communication, the time required to establish a connection may be longer.
If the timeout value is too short, the connection may fail even though the device can actually respond normally.
The name and setting method for this configuration item differ depending on the OPC UA client you use.
Security token update processing
Security token update processing for the OPC UA client takes about 10 seconds.
If communication overlaps during the update processing, data updates may temporarily stop or communication may be interrupted, but it will usually recover automatically.
Data acquisition cycle
Every day at UTC 0:00, the processing to delete historical data files whose data retention period has expired (maintenance processing) is executed.
During this processing, due to limitations in data save processing, the data acquisition cycle set on the client side may be temporarily shifted.
After completion of the processing, the normal data acquisition cycle will be restored.
Startup Time
After the power of this product is turned on, it takes approximately 2 minutes to complete the restoration process (maintenance processing) of the historical data files (in the case of 40 read commands and 8 write commands).
During this process, communication with OPC UA clients is not available.
Communication will be automatically enabled once the process is complete.