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| Full name | Description | Unit | Default value | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Defines the time interval for the server to send the information about the change of monitored items within the instance subscription by "Publish message". | mi:ss.mss | 00:05.000 | ||||||
| If the client does not send the request for data till the time defined by (LifeTime Count * Publishing Interval), the subscription expires. The value should be minimally 3 times higher than the "Requested Max KeepAlive Count". | Number | 1000 | ||||||
| If the objects of subscription are not changed, the server will send a keep-alive message after elapsing the time (Max Notifications Per Publish * Publishing Interval). The client will confirm this message when it sends a new request for data. | Number | 5 | ||||||
| The parameter defines the maximum number of notifications about the object change, which the server can send in one "Publish message". Zero indicates that the number of notifications is unlimited. | Number | 0 | ||||||
| The parameter enables/disables the publishing within the subscription. | YES/NO | YES | ||||||
| It defines a relative priority of a subscription. If the server should send more notifications, the subscription with higher priority is preferred. | 0-255 | 0 | ||||||
| This parameter enables creating an object queue with the defined length on the OPC UA server's side for each monitored item in a subscription. | Number | 0 | ||||||
| Timestamps used while reading a value:
| - | Server | ||||||
| Timestamps used to write a value:
Note: If the OPC server does not support the writing of timestamps, according to the standard it should return the Bad_WriteNotSupported (2155020288) error code. | - | None | ||||||
| StatusCode item will be used when writing. Note: According to the standard, the OPC UA Wrapper returns the Bad_WriteNotSupported (2155020288) error code if the StatusCode entry is used when writing to the OPC DA Server version 2.05a. | YES/NO | YES | ||||||
| When an item of an array is written, the entire array is read first and then written. If this parameter is set to NO, only a specific array item is written, Note: According to the standard, if the OPC server does not support writing a specific array item, it should return the Bad_WriteNotSupported (2155020288) error code. Note: If this parameter is active, the "Write only" parameter must not be set at the I/O tag which addresses an item of the array. | YES/NO | NO | ||||||
| Values that are not older than the specified time interval (compared to the timestamp of the current value of the I/O tag) will be accepted. After writing, it may happen that the value read back is older (usually by several ms) compared to the time of writing unless the communication computer and the OPC UA server have exact time synchronization. Error messages may appear in the line log: | hh:mi:ss | 00:00:00 | ||||||
| A way of reading values:
Note: The Subscribe+Read and Read modes should only be used if there is a problem with standard communication, as they are less efficient and have a higher overhead. | Subscribe Subscribe+Read Read | Subscribe | ||||||
| Ignoring filter parameters in the I/O tag configuration (Sampling type, DeadBand type, Trigger type). | YES/NO | NO | ||||||
| The maximum number of consecutive unconfirmed Publish requests (to which OPC UA server does not reply with a Publish Message), after which the connection will be closed. A value of 0 causes the connection to not be closed. Note: This parameter can be used to speed up the detection of a broken connection to the OPC UA server. | - | 0 |
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