Writer Group Properties
Items representing a Publisher WriterGroup.
The Writer Group item type has the following properties:
| Name | Description | ID | Flags |
|---|---|---|---|
| DataSetOrdering | The DataSetOrdering defines the ordering of the DataSetMessages in the NetworkMessages. The default value is Undefined. | 11210 | Persisted, Hidden, Enumerated |
| Diagnostics level | Define the level of diagnostics to be created. | 10150 | Persisted, Enumerated |
| Enabled | Whether the item is enabled or not. | 10100 | Persisted |
| GroupVersion | The parameter GroupVersion with DataType VersionTime defines the expected value in the field GroupVersion in the header of the NetworkMessage. The default value 0 is defined as null value, and means this parameter shall be ignored. | 11200 | Persisted, Hidden |
| JsonNetworkMessageContentMask | The parameter NetworkMessageContentMask defines the optional header fields to be included in the NetworkMessages produced by the WriterGroup. The DataType for the JSON NetworkMessage mapping is JsonNetworkMessageContentMask. (See doc OpcUa Part 14 1.0.4 chapter 6.3.2.2.1) | 11100 | Persisted, EnumeratedFlags |
| KeepAliveTime | The KeepAliveTime with DataType Duration defines the time in milliseconds until the Publisher sends a keep alive DataSetMessage in the case where no DataSetMessage was sent in this period by a DataSetWriter. The minimum value shall equal the PublishingInterval. | 11030 | Persisted |
| Max NetworkMessage queuesize | Maxium number of NetworkMessages in the internal queue. | 11025 | Persisted |
| MaxNetworkMessageSize | The maximum size in bytes for networkmessages created by the Writergroup. It refers to the size of the complete message including padding and signature without any additional headers added by the transport protocol mapping. If the size of a message exceeds the "Max message size", the behaviour depends on the message mapping./td> | 11010 | Persisted |
| MessageRepeatCount | The MessageRepeatCount with DataType Byte defines how many times every NetworkMessage is repeated. The default value is 0 and disables the repeating. | 11060 | Persisted, Hidden |
| MessageRepeatDelay | The MessageRepeatDelay with DataType Duration defines the time between NetworkMessage repeats in milliseconds. The parameter shall be ignored if the parameter MessageRepeatCount is set to 0. | 11065 | Persisted, Hidden |
| AMQP partitionkey | The key used to generate a hash code which decides the partition the message will be sent to when using AMQP. | 11015 | Persisted |
| Priority | The Priority with DataType Byte defines the relative priority of the WriterGroup to all other WriterGroups across all PubSubConnections of the Publisher. If more than one WriterGroup needs to be processed, the priority number defines the order of processing. The highest priority is processed first. The lowest priority is 0 and the highest is 255. | 11040 | Persisted, Hidden |
| PublishingOffset | The SamplingOffset with the DataType Duration defines the time in milliseconds for the offset of creating the NetworkMessage in the PublishingInterval cycle. Any negative value indicates that the optional parameter is not configured. In this case the Publisher shall calculate the time before the PublishingOffset that is necessary to create the NetworkMessage in time for sending at the PublishingOffset. | 11240 | Persisted, Hidden |
| PublishInterval | The PublishingInterval with the defines the interval in milliseconds for publishing NetworkMessages and the embedded DataSetMessages created by the related DataSetWriters | 11020 | Persisted |
| Quality | Item quality | 3 | ReadOnly |
| AMQP main EntityPath | A string parameter specifies the EntityPath in the broker. | 11053 | Persisted |
| AMQP backfill EntityPath | A string parameter specifies the EntityPath in the broker. | 11054 | Persisted |
| MQTT main topic | The topic string parameter specifies the queue this WriterGroup send messages to. | 11050 | Persisted |
| MQTT backfill topic | The topic string parameter specifies the queue this WriterGroup send messages to. | 11051 | Persisted |
| RequestedDeliveryGuarantee | The RequestedDeliveryGuarantee parameter with DataType BrokerTransportQualityOfService specifies the delivery guarantees that shall apply to all NetworkMessages published by the WriterGroup unless otherwise specified on the DataSetWriter transport settings. | 11055 | Persisted, Enumerated |
| Rights | Item access rights | 5 | ReadOnly |
| SamplingOffset | TThe SamplingOffset with the DataType Duration defines the time in milliseconds for the offset of creating the NetworkMessage in the PublishingInterval cycle. Any negative value indicates that the optional parameter is not configured. In this case the Publisher shall calculate the time before the PublishingOffset that is necessary to create the NetworkMessage in time for sending at the PublishingOffset. | 11230 | Persisted, Hidden |
| Time | Item timestamp | 4 | ReadOnly |
| Type | Item canonical datatype | 1 | ReadOnly |
| UadpNetworkMessageContentMask | The parameter NetworkMessageContentMask defines the optional header fields to be included in the NetworkMessages produced by the WriterGroup. The DataType for the UADP NetworkMessage mapping is UadpNetworkMessageContentMask. | 11220 | Persisted, Hidden, EnumeratedFlags |
| UserExtra | UserExtra is a static Json-part that is added to the Json_spesial message | 11045 | Persisted |
| Value | Item value | 2 | ReadOnly |
| WriterGroupId | The WriterGroupId with DataType UInt16 is an identifier for the WriterGroup and shall be unique across all WriterGroups for a PublisherId. All values, except for 0, are valid. The value 0 is defined as null value. | 11000 | Persisted, ReadOnly |
See also Predefined Item Properties and OPC DA Properties