9 OPC UA VariableTypes

9.1 JoiningDataVariableType

The JoiningDataVariableType is a subtype of the BaseDataVariableType. It is to describe common sematic required for variables in the system. In this version of the specification, it provides information about physical quantity and Engineering Units. It is formally defined in Table 203.

The component Variables of the JoiningDataVariableType have additional Attributes defined in Table 204.

PhysicalQuantity is to determine the type of the physical quantity associated to a given value(s). It has the following pre-defined values which shall be used for each instance of this type.

0 – OTHER

1 – TIME

2 – TORQUE

3 – ANGLE

4 – IMPULSE

5 – DISTANCE

6 – AREA

7 – VOLUME

8 – FORCE

9 – PRESSURE

10 – VOLTAGE

11 – CURRENT

12 – RESISTANCE

13 – POWER

14 – ENERGY

15 – MASS

16 – TEMPERATURE

17 – FREQUENCY

18 – JOLT

19 – VIBRATION

20 – NUMBER

21 – LINEAR_SPEED is the change of distance over time.

22 – ANGULAR_SPEED is the change of angle over time.

23 – LINEAR_ACCELERATION is the change of DISTANCE_SPEED over time.

24 – ANGULAR_ACCELERATION is the change of ANGULAR_SPEED over time.

25 – TORQUE_SPEED is the change of torque over time.

26 – TORQUE_ACCELERATION is change of TORQUE_SPEED over time.

27 – TORQUE_PER_ANGLE_GRADIENT is the change of torque over angle.

28 – TORQUE_PER_ANGLE_GRADIENT2 is the change of TORQUE_PER_ANGLE_GRADIENT over angle. Example: It is used for yield and snug detection. It represents the change of the slope in a torque over angle graph.

0:EngineeringUnits defines the engineering unit of the values.

Note: The quantity and units of the value is of importance, and it is going to be defined in harmonized way.

Note on Physical Quantity and Engineering Units

JoiningDataVariableType describes a minimal way to provide the PhysicalQuantity and EngineeringUnits properties for a given value.

An application can ensure that those are available by using a corresponding Conformance Unit defined for this use case.

If an application does not provide the EngineeringUnits for a given value, it is assumed to be in International System of Units (SI).

9.2 JoiningSystemResultType Definition

The JoiningSystemResultType is a subtype of 0:BaseVariableType. It is used to expose the information of the 5:ResultDataType in individual sub-variables. The 5:ResultMetaData have the same meaning as defined by the DataType in section 10.1.

It is formally defined in Table 205.

The components of the JoiningSystemResultType have additional subcomponents which are defined in Table 206.

Refer section 10.1 for the descriptions of the variables.

9.3 JoiningSystemEventContentType ObjectType Definition

The JoiningSystemEventContentType is a subtype of 0:BaseVariableType. It is used JoiningSystemEventType and JoiningSystemConditionType.

It is formally defined in Table 207.

JoiningTechnology is a human readable text to identify the joining technology which has triggered the event. Examples: Tightening, Gluing, Riveting, Flow Drill Fastening, etc.

AssociatedEntities is a list of identifiers of various entities/objects available in the given system. Example: An event maybe associated with Asset, Result, Joint, Error, etc.

EventText is a human readable text related to the context of the event.

EventCode is a system specific event code associated with the given event.

ReportedValues is a list of values associated with the given event payload. Example: If it is an over temperature event, then the ReportedValue can be the measured value along with the corresponding limits.