OPC Item ID´s
Hello everyone,
I have a problem when browsing OPC TAG´s (ABB.AfwOpcDaSurrogate)
Can someone explain why the Item ID is always presented differently?
1. For example once the Item ID is presented like this: Root/Control Network/xxx/Applications/App1/ControlModules/xxx/TAGNAME:Value (object type AIS01 / PP_FunctionLib6.1-0)
2. For another TAG the Item ID is presented like this: {GUID}:Value (object type AIC01 / PP_FunctionLib6.1-0)
3. And the third variant is this: TAGNAME:Value (object type AIC01 / PP_FunctionLib6.1-0)
Example Nr.2 and Nr.3: the object type is the same and also the object path is the same .... WHY the different Item ID´s ???
please help !
I have a problem when browsing OPC TAG´s (ABB.AfwOpcDaSurrogate)
Can someone explain why the Item ID is always presented differently?
1. For example once the Item ID is presented like this: Root/Control Network/xxx/Applications/App1/ControlModules/xxx/TAGNAME:Value (object type AIS01 / PP_FunctionLib6.1-0)
2. For another TAG the Item ID is presented like this: {GUID}:Value (object type AIC01 / PP_FunctionLib6.1-0)
3. And the third variant is this: TAGNAME:Value (object type AIC01 / PP_FunctionLib6.1-0)
Example Nr.2 and Nr.3: the object type is the same and also the object path is the same .... WHY the different Item ID´s ???
please help !
Answers
Seems the ABB.AfwOpcDaSurrogate shows all ways to address an item. Since there are multiple ways to address an item, your opc-browser shows multiple "mirrors" of most items.
The OPC DA Surrogate will resolve an object to the correct name, path and GUID only if the Object name is unique in the 800xA System.
For your third party historian, use the "Object:Aspect:Property" and ensure that the "Object" is unique within the 800xA system. You can use the 800xA search tool to confirm this.
The {GUID} and /path/to/your/object syntax is simply a longer way of identifying the same object. if you cannot make the object name unique (sometimes this happens with PLC Connect, QCS Control Systems and other products) then you can use either the Path or GUID to identify the correct object. You only require enough "path" to identify a unique object. So for example "parent1/AIS01:Function Block:Value" and "parent2/AIS01:Function Block:Value" will resolve to unique objects.
A known problem with the pulp and paper library is that you **MUST** set the "Name" property of every P&P Lib Element, otherwise the name will default to the same non-unique value for every block. i.e. Every AIS function block in the system defaults to the name "AIS01".
For your third party historian, use the "Object:Aspect:Property" and ensure that the "Object" is unique within the 800xA system. You can use the 800xA search tool to confirm this.
The {GUID} and /path/to/your/object syntax is simply a longer way of identifying the same object. if you cannot make the object name unique (sometimes this happens with PLC Connect, QCS Control Systems and other products) then you can use either the Path or GUID to identify the correct object. You only require enough "path" to identify a unique object. So for example "parent1/AIS01:Function Block:Value" and "parent2/AIS01:Function Block:Value" will resolve to unique objects.
A known problem with the pulp and paper library is that you **MUST** set the "Name" property of every P&P Lib Element, otherwise the name will default to the same non-unique value for every block. i.e. Every AIS function block in the system defaults to the name "AIS01".
by erik
Please check if your TAGNAME is unique
by ruppi Rank: 407 on 7/16/2019 12:52:20 AM | Like (0) | Report
Hi, I have already checked for duplicate names .... unfortunately this is not the reason.
by ruppi Rank: 407 on 7/16/2019 1:04:03 AM | Like (0) | Report
I am using a non-ABB Software to record Long term Trends.
If the ID must be entered differently for each Signal, it makes a lot of work with several thousand signals.
If the type of the itm-ID were the same, I could mostly automate my config-file.
by erik
Maybe TAGNAME:Value and {GUID}:Value can both used and have the same result. I would try that. I the case of the full path you can check also, but it's strange. If 800xA use the full path there's normal the identifier not unique.
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