L-DALI User Manual
362
LOYTEC
Version 5.2
LOYTEC electronics GmbH
Figure 245: Client browsing the OPC tag namespace on a L-INX.
8.5.2.1 Analog
Analog data points are exposed as a one-to-one mapping to OPC tags. For each analog data
point, an OPC tag is created. The OPC tag contains a number of OPC properties, which are
derived from the data point’s properties:
Item Canonical Data Type (SmallInt): This property indicates the data type ‘5’
(Double).
Item Value (Double): The present data point value.
Item Quality (SmallInt): The value quality. It is “good” if the data point is in normal
state, or “uncertain” if the data point has an off-normal state, e.g., offline or unreliable.
Item Timestamp (Date): This property contains the timestamp of the last value update.
Item Access Rights (Integer): This property defines whether the tag is read-only or
read/write.
Item Description (String): This is the description of the data point.
Item EU Type (Integer): This property is ‘1’.
High EU (Double): This is the analog maximum value of the data point.
Low EU (Double): This is the analog minimum value of the data point.
EU Units (String): This is the human-readable engineering units text of the data point.
8.5.2.2 Binary
Binary data points are exposed as a one-to-one mapping to OPC tags. For each binary data
point, an OPC tag is created. The OPC tag contains a number of OPC properties, which are
derived from the data point’s properties:
Item Canonical Data Type (SmallInt): This property indicates the data type ‘11’
(Boolean).
Item Value (Boolean): The present data point value.
Item Quality (SmallInt): The value quality. It is “good” if the data point is in normal
state, or “uncertain” if the data point has an off-normal state, e.g., offline or unreliable.
Item Timestamp (Date): This property contains the timestamp of the last value update.
Item Access Rights (Integer): This property defines whether the tag is read-only or
read/write.
Item Description (String): This is the description of the data point.
