Object PmVar (Variable)
object represents one data variable
of the Pma object
Such variable holds more information in itself (value, name, index, etc.), and so it is represented by the object. Then the object has got this information as its properties.
the PmVar object can be created in objects: PmaData, PmaOpcClientGroup, PmaCommGroup, PmaTrendGroup, PmaCommMsg.
Properties and methods:
|Owner|| Returns reference to the PmVar object owner in the tree of Pma objects|
|Extension|| Data extension access|
|GetBit|| Returns the bit in the value of the variable|
|ChangedOnLastWrite|| Flag showing if value was changed by last writing|
|Index|| Index of the variable in the object|
|Name|| Name of the variable|
|Note|| Note of the variable|
|Quality|| Quality of the variable value|
|SetBit|| Sets the bit in the value of the variable|
|TimeChange|| Time of last writing into the variable that changed value|
|TimeWrite|| Time of last writing to the variable|
|Unit|| Physical unit of the variable (only for PmaData and PmaTrendGroup)|
|Value|| Value of the variable|
|ValueBeforeChange|| Last value before changing value to current|
Obsolete properties and methods:
|Bit|| Value of one bit of the variable|
|Data extensions|| The data extensions are PROMOTIC system components, extending the basic functionality of PmVar data items (variables). Each data extension type is used for specific purpose (e.g. limit excess alarm, OPC server or connection to the PmaComm object, trends, etc.).|
In the script PmVar
variables can be obtained following ways:
//by the Item method of these objects, for example
oTemperature2 = pMe.Pm("/Data").Item("Temperature2");
//or directly by the Pm method with the #vars identifier, for example
oTemperature2 = pMe.Pm("/Data/#vars/Temperature2");
The PmVar object directly contains only basic functionality (most important common properties). The functionality of the PmVar can be extended by adding one or multiple data extensions.
Each data extension is then contained in the PmVar object in form of a subobject (e.g. ExtAlarmAnalog, ExtComm, ...), accessible by the PmVar.Extension method or by #ext identifier.